operation manual gc3420a - mrclab · following guidelines: 9 1. ... 4.1 selection of transformer...

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Gas Chromatography (Volume 1)

OOppeerraattiioonn MMaannuuaall

GGCC34203420AA

PLEASE READ THIS MANUAL CAREFULLY BEFORE OPERATION

3, Hagavish st. Israel 58817 Tel: 972 3 5595252, Fax: 972 3 5594529 [email protected]

MRC.VER.01-8.13

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CONTENTS SECTION ONE INTRODUCTION ................................................................................... 3

SECTION TWO INSTALLATION .................................................................................... 8

SECTION THREE OPERATION..................................................................................... 44

SECTION FOUR INJECTOR .......................................................................................... 68

SECTION FIVE DETECTCRS...................................................................................... 130

1Thermal Conductivity Detector..................................................................................... 130

2 Flame Ionization Detector ........................................................................................... 138

3 Electron Capture Detector ........................................................................................... 149

4 Thermionic Specific Detector ...................................................................................... 165

5 Flame Photometric detector ........................................................................................ 179

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SECTION ONE INTRODUCTION

1 General

34 Series Gas Chromatograph (See Fig.1 and Fig. 2) guides you through operation via the on line

display. It can accommodate two packed column injector or one packed column and one capillary

injector. Two ionization detectors or one TCD detector can be installed. The column oven accepts

glass column, packed column or fused silica capillary columns.

The self-diagnostic capability of 34 Series GCs allows you to test the instrument conditions and to

detect and identify the faulty circuitry. In addition, the continuous testing is done by the instrument to

detect possible electronic failures. If such failures are found, the protective action is automatically

taken and you are notified via the display.

2 Use of this manual

This manual will guide you in using 34 Series GCs. Method building exercises are provided for

instrument familiarization.

Prior to beginning operation, the instrument must be fully installed by following the installation

procedures mentioned in Chapter two or invite your local dealer.

This operator’s manual has some important conventions, such as: the use of boxed warnings, cautions

and notes. This information is set out from the test for emphasis and should be followed to assure

optimum instrument operation and operator protection.

3 Instruction descriptions

Figures 1 and 2 shows the location of switches, fuses, connectors, gas inlets and various options. Use

Figure 2 as quick reference to other manual section where detailed information is located.

4 Before you begin

If you are installing the GC yourself, follow the installation procedures given in INSTALLATION.

If your instrument is installed, turn to OPERATION to begin.

4

Figure 1

5

Figure 2-1

6

Figure2-2

8

Safety Practices

General

The following safety practices are intended to insure. The safe operation of the equipment.

Electrical Hazards

1. Removal of some panels expose potentially dangerous voltages. Such panels will bear a warning

label noting the hazard. Disconnect the instrument from all power sources before removing

protective panels.

2. When power cord plugs must be changed to conform to on-site power receptacles, be sure to

adhere to color coding and polarity describe in the manual.

3. Replace blown fuses with size and rating stipulated on the fuse panel or holder, and in the manual

where listed.

4. Replace or repair faulty or frayed insulation on power cords.

5. Check actual line voltage to confirm it is the instrument is wired. Be sure power cords are plugged

to correct voltage sources.

Compressed Gas Cylinders

1. Compressed gases should be stored and handled strictly in accordance with relevant safety codes.

2. Fasten all cylinders securely to an immovable structure or permanent wall.

3. Store or cylinders only in a vertical position. Do not move or transport cylinders with regulators

attached.

4. Store cylinders in a well ventilated area away from heat or ignition sources.

5. Mark all cylinders in a well so there can be no doubt as to contents.

6. Use only approved regulators and tubing connections.

7. Connect cylinders to instrument only with clean tubing whose pressure rating is significantly

greater than highest outlet pressure from regulator.

General Precautions

1. Perform periodic leak checks on supply lines and pneumatic plumbing.

2. Arrange gas lines so they can not become kinked, punctured, or otherwise damaged, and will not

interfere with foot traffic.

3. Store organic solvents in fireproof, vented, clearly labeled cabinets identifying toxic and/or

flammable materials.

4. Do not allow flammable and/or toxic solvent wastes to accumulate. Follow a regulated, approved

waste disposal program. Never dispose of such products through the municipal sewage system.

Exhaust system

Fumes and heat emanating from GC detectors is minimal. Except when testing hazardous chemicals,

no special exhaust ducting is required in a well ventilated room. If ducting is installed, observe the

following guidelines:

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1. Use only fireproof ducting.

2. Install blower at duct outlet.

3. Locate duct intake far enough from the detector to avoid any vibration or air current effect on

detector performance.

4. Check duct suction periodically.

Radiation safety

(Radioactive Source Detectors)

1. Note and comply with all NOTES, CAUTIONS and WARNING appearing in the Ni63 ECD

manual ECD.

2. Perform scheduled test for removable radioactive contamination as prescribed in the above

publication.

3. NOTE: It is the responsibility of the user to be sure that leak test schedules a procedures are

comply with.

Burn Hazard

Heated zones of gas chromatographs can remain hot for a considerable time after the instrument

power has been turned off. To prevent painful burns resulting from contact with hot surface (injector

nuts, column, etc.) be sure that all heated areas have cooled to room temperature, or wear adequate

hand protection.

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SECTION TWO INSTALLATION

1 General

This section details the installations required prior to operation of 34 Series GC. The instrument is

designed to be operator-installed using the detailed procedures provided in this section. You will also

be able to check out your instrument by running the test sample.

Should you experience difficulties during the installation, please ask your local dealer to assist you.

2 Unpacking and acceptance

After unpacking the instrument, check it carefully for the evidence of shipping damage or rough

handling. Any evidence of the damage should be reported immediately to the carrier and your local

dealers. After so, inform of the manufacture.

2.1 Removal of Fan Motor Shipping Dowel and Shipping Caps

Remove the instrument and check the contents of the accessory package against the enclosed list. Any

discrepancies or missing items should be reported to your local dealer.

Removal of Column Oven Fan Motor Shipping dowel.

To preventing excess load vibration during the transportation, use a plug to fix the fan and the motor

of the column oven. Before operation, detach this plug from the hole located at the rear of the

instrument. If the instrument is required to be shipped again, the plug must be re-installed.

Removal of Shipping Caps and Plugs

Remove plastic or paper caps and plugs. Detach plastic or paper caps under the detector cover,

instrument top cover, and at rear of instrument. If the caps are all removed from the injector or the

detector fittings or the rear of the instrument, replace with Swagelok plugs to prevent the

contamination of the system until the column is installed or the gas supplies are connected.

3 Site preparation

Site preparation should be complete at this time. The instrument should be put on firm, even and

reliable work-bench. Large temperature change and air convicted circulation should be avoided

(Change range of environmental temperature is + 10℃~40℃). Enough work-bench space should be

CAUTION

Carefully inspect the oven interior and remove all plastic and/or paper

shipping caps and restraints before electrically connecting and heating

the instrument.

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allocated to permit the installation of the peripheral instrumentation such as data system, gas

generators and recorders, etc. The table 1 is shown for the dimensions of the peripheral devices.

Table 1

Name H (mm) W (mm) L (mm) Remark

34 Series 510 590 610

Recorder

Integrator

Depends on Model selected

Depends on Model selected

5cm space must be remained at both

sides and the rear of the instrument.

4 Power requirements

34 Series GCs requires a stable power supply:

Voltage: 220V/110V ±10%;

Frequency: 50Hz /60Hz ±0.5Hz;

Current: ＞8amps.

A diagnostic message will be displayed if A.C. line polarity is reversed or if the ground connection is

faulty. Refer to the diagnostics/troubleshooting section for the diagnostic information.

Power cord wiring is shown in Fig 2A. NOTE: Potential between neutral and ground should not

exceed 3 volts.

CAUTION

Hot exhaust from the column oven exists through the rear of the

instrument. Avoid diverting heat on the other electronic

NOTE

Each 34 Series GCs requires individually power

supply.

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Fig. 2A Diagram of power cord wiring of main unit

4.1 Selection of transformer input

The transformer input select switch (S1) is located near the rear of the Mother PCB (See Fig.2-2). For

an 110V/120V range instrument, UP (high) is 120V nominal and down is 110V nominal. For a

220V/240V range instrument, UP is 240V nominal and DOWN (low) is 220V nominal. These ranges

permit modification to the voltage available at the most sites. The instrument is shipped with this

switch in the high voltage (UP) position.

The specified tolerance for the line voltage is ±10% around the nominal value, but the short-term

drops of 20% or more below nominal are typically tolerated. If the line voltage falls to a level where

the correct operation is impaired, the GC will be switched off and a power fault message will be

generated, including the time of the failure: PO-WEL FAIL.

It is recommended that the switch (S1) is left in the high position unless the instrument detects the

power failures during the normal operation. If the GC is operated normally with the switch in the low

position, even if the line voltage is over 110% of the nominal value, the internal temperature of the

instrument will be elevated and the reliability is reduced.

If it is necessary to change the position of this switch due to a low line voltage available at your

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location, follow the procedures below.

1. Determine the full range of the line voltage variations over 24 hours period. If the voltage stays

between 198V to 242V, set the switch to the low voltage position. If the voltage stays between 216V

to 264V, select the high (UP) setting. If the voltage does not remain within either of these ranges,

please call your local dealer to see if a power line conditioner is required.

2. To change the select switch setting of the instrument transformer, disconnect the instrument from all

powers; remove the detector cover, instrument top cover and high voltage cover.

3. Locate S1 on the Mother PCB (See Fig. 2-2). Observe if it is shipped in the correct position for your

voltage range. If there is a problem in the low position, please consul your local dealer to see if a

power line conditioner is required.

Figure 2-2

WARNING

HIGH VOLTAGE PRESENT

Dangerous voltages are exposed in the following steps. The

instrument must be disconnected from all powers.

WARNING

Do not attempt to change an instrument configured for the

110/120V range to 220/240V range, or vice versa, or the

warranty will be voided.

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4.2 Power switch.

The instrument power switch is located at the top left rear of the instrument. Up is ON and Down is

OFF.

4.3 Fuse Requirements

The fuses for 34 Series GCs are located on the instrument back panel, Mother PC Board and on

individual PC Boards within the instrument. Refer to table 2 for fuse ratings, locations and circuits

affected.

5 Battery backup and power on the instrument

Battery back-up. The battery back-up allows 34 Series GCs to protect the instrument memory when (1)

the instrument is shut down to change the boards or make other hardware changes or (2) to protect the

memory function during the temporary power outages. If the battery switch is off, the instrument

method will be lost.

34 Series GCs is shipped with the battery switch in the ON (UP) position (See Fig. 2-3), the moment,

the final adjustment method is still stored in the memory. For the method of 34 Series GCs, the

method is “1). If the method is no change at all, it is available to operate GC test.

If the GC is disconnected from the power for a long period of time, or if it is to be stored, the battery

switch on the CPU board should be moved to OFF position (See Fig.2-3).

Table 2 Specifications of fuses

Name Specification Part Number Position Circuit

F101 4A, S/B 67-137470-00

67-135440-00

Back panel Primary transformer

F102 10A 67-130510-00

67-130510-00

Back panel Heater power

F1 10A 67-130510-00 Mother PCB +5V VDC supply

F2 4A 67-133440-00 Mother PCB Transformer load

F3 4A·ZA·· 67-133440-00

67-132420-00

Mother PCB Line powered loads

F1 1A, S/B 67-135410-00 PCB of power supply ±15VDC supply

F1 1A, S/B 67-135410-00 PCB of power supply ±15VDC supply

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F1 3A 67-132430-00 PCB of E. events 24VDC for solenoids

F1 5A, S/Bˉ 67-137450-00 FID PCB Igniter

F1 5A, S/B 67-137450-00 FPD PCB Igniter

F1 5A, S/B 67-137450-00 FID/TSD PCB Igniter

F2 2A, S/B 67-135420-00 FID/TSD PCB Bead supply

F1 1/4A, S/B 67-135325-00 ECD PCB Pulse supply

F1 1A, S/B 67-135410-00 TCD PCB Bridge supply

F1 2A, S/B 67-135420-00 P/P PCB Motor supply

Fig. 2-3 Position of battery switch

5.1 Power on GCs

1 Switch on the power switch of the main unit located at the upper left rear of the instrument.

2 Press SHIFT INSTR TEST to run through the automatic tests. The instrument will be running

solenoids, valves and fans, etc. off and on in the initial testing. The front panel lights will be turned on

in sequence from left to right.

3 Upon the completion of the tests, the message TESTS OK is displayed (it shows successful). If this

message is not displayed within 40 seconds, or if any fault messages are displayed, refer to the

Diagnostics/Troubleshooting manual.

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4 If the instrument does not start or seems to be behaving abnormally, refer to the

Diagnostics/Troubleshooting manual.

6 Gas requirements and gas connections

Gas requirements:

Select combustion gas and carrier gas according to the detectors you used. Table 3 lists various kinds

of the gases for the detectors common used in GCs. Table 4 is shown for the gases equipped with the

accessories.

Table 3 Gases used for various kinds of detectors

Capillary flow ml/min.

Detector

Inlet

pressure

Purity

Packed

column

Flow

Ml/min.

Split/

Non-

split

Large

Aperture

injection

Capillary

injection

Mark

TCD

Carrier

He,N2,H2

414Kpa

60Psig

99.998%

10-80

1-30

In N2, H2O ≤

3PPM O2 ≤

5PPMO2

De-oxygen

Filter should be

used.

ECD

Carrier:

N2,He

414Kpa

60Psig

99.998%

20-60

＜1000

1-30

5-10

In Ar.CH4, H2O

≤

0.02PPM, O2 H2

≤ 1PPM. ECD

can be washed

with

H2.De-oxygen

Filter should be

used.

FID

Carrier:

He,N2,H2

414Kpa

60Psig

276KPa

99.998%

99.995%

Breathing

level

20-60

20-40

＜1000

20-40

3-30

20-40

5-10

20-40

H2 is provided

With Hydrogen

Generator.

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Detector

H2, air

40Psig

60Psig

414KPa

200-400

200-400

200-400

200-400

TSD

Carrier:

He,N2

Detector

H2,air

414KPa

60Psig

276KPa

40Psig

60Psig

274KPa

99.999%

99.995%

Breathing

level

20-60

3-6

165-185

＜1000

3-6

165-168

1-30

3-6

165-168

5-10

3-6

200-400

Hydrogen press-

Ure adjuster &

Pressure meter

Of TSD must be

Installed.

FPD

Carrier:

He or N2

Detector

H2, air

414KPa

60Psig

276KPa

40Psig

60Psig

276KPa

99.998%

99.998%

Breathing

level

20-60

120-160

100-160

150-190

＜1000

120-160

60-100

150-190

1-30

120-160

60-100

150-190

5-10

120-160

60-100

150-190

In N2, H2O ≤

3PPM

O2 ≤ 5PPM.

Duel

Flame requires

Two air piping &

Adding gas valve

Deoxidized filter

Should be used.

Gas typical impure contents are shown as follows:

He: CO＜0.25PPM

Ar＜0.1PPM

Ne＜10PPM

N ＜10PPM

N2＜25PPM

N2: O2＜10PPM

H2O＜5PPM

Hydrocarbon＜1PPM

H2: O2＜5PPM

H2O＜5PPM

Hydrocarbon＜1PPM

Air: CO＜10PPM

CO2＜500PPM

Oil＜0.02PPM

H2O＜0.02PPM

CH2＜20PPM

Table 4 Gases used for equipped accessories

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Application Recommended gas Inlet pressure

800 series auto-sampler Air 414Kppa (60Psig)

Valve drive Air 414KPPa (60Psig)

Low temperature (LCO2) Liquid Status CO 5865Kppa(850Kpa)

Low temperature (LN2) Liquid nitrogen 207-345Kpa

(30-50)Psig

NOTE: Special valves are required for liquid nitrogen and liquid hydrocarbon.

Installation of secondary pressure adjuster (Oxygen meter)

The secondary pressure adjuster must be used for the carrier gas and air provided with the cylinder.

The low pressure of the adjuster should be 0-100Psig. The inlet pressure of He, N2, Ar/CH4 or other

carriers should be 414Kpa (60PSI) nominal, air is 414kpa, H2 is 276Kpa (40PSI), or H2 is supplied by

hydrogen generator.

Attention points for using cylinders

Attention matters of safe operation in the laboratory must be followed when it is stored, used and

shipped.

1) Never allow to move the oxygen cylinder. A safe cap must be mounted on the cylinder during

transportation.

2) The cylinder must be fixed well with bicycle chain or belt when putting it in the laboratory or

other site.

3) Remarks must be made on the cylinder to show whether the cylinder is full or using now.

4) The residual gas of 100Psig (60Kpa) at least must be existed in the empty cylinder. Close the

cylinder valve and put it in “Empty cylinder area”. Remake must be made on the empty cylinder with

date.

5) Never allow to put the cylinder in the area with the temperature high than 50℃.

Connection of gas piping

All gas inlet connector will be connected at the rear of the instrument.

The soft tube equipped with the instrument can be used as the connecting tube from the gas source to

the instrument.

Gas filter

The filter is used to modify the purity of the carrier gas. Table 5 lists various kinds of the filter

provided by our company.

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Table 5 Filters provided by our company

Filter Standard/

optional

Application Location

Carrier filter

68-000070-00

Standard for 34

Series

Determinate

Pollution from hydrocarbon

and water of cylinder

Rear of instrument

Deoxidized filter

68-000056-01

ECD standard

FZD,FPD TSD

optional

Decrease O2 and moisture in

inert carrier gas

Rear of instrument

Mini-filter

03-917134-01

Standard for 34

Series

Prevent pollution of moisture

or hydrocarbon when opening

diaphragm or replacing column

Inside of gas

piping

Replacement & mark of gas filters

When the filters are reached up to the using time stipulated (See table 5), the replacement is required.

Operator should record the installed date and some other information, take marks on every filter. If the

baseline is changed a lot, which shows the replacement of the filter is required.

The filters are common used to determinate the impurity in high pure gases. It cannot determinate all

pollutions in low pure gases. Therefore, low pure gases should not be used any more. Allowable

lowest value pure is listed in the table 3.

Carrier filter and deoxidized filter are all mounted on the rear of the instrument. Mini-filter is mounted

inside of the gas piping part.

Procedures for detaching the mini-filter are as follows:

1) Cut off gas source and power supply of the instrument; remove top cover in order to install the

filter from the top part.

2) Loosen the connector of the filter and separate from the gas piping.

3) Install a new filter and make mark on the filter, tighten the connector. Start the gas source and

power supply. Make leak checking.

CAUTION

The Deoxidized filter can remove out O2 from the carrier, but the deoxidized capability will be

decreased quickly in the air.

On this occasion, during installing it, don’t remove the plugs of both sides at the filter unless all

gas piping systems connected are ready. Set the carrier gas flow in the air piping to

50-100ml/min., and then remove the inlet plug of the filter and connect it to the gas piping. The

moment the outlet plug cannot be removed until the filter is stayed in the negative pressure.

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7 Connection of peripherals and data processing system

The detector signal outlet panel is located on the left side of the instrument. See Fig.2-4. The detector

A and B signal outputs are available for chart recorder (RCD, 1mv), integrator (INTEG, 1V) and

computer (CMPTR, 10V).

7.1 Chart recorder connections

Refer to Fig.2-4 for connection between 34 Series GCs and a 1mv chart recorder. Orient the recorder

cable properly when connecting to the GC. Refer to Fig. 2-4.

Results and prescribed test procedures in this manual are for 1mv full scale recorder. If a recorder with

a different span is used, remember to scale the results to 1mv for the comparison.

Fig. 2-4 Connection of 1mv chart recorder

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7.2 Integrator connection

The connection between 34 Series GCs and the integral is as same as the connection of chart recorder.

But only note: Orient the integrator cable properly when connecting to the GC. Refer to Fig. 2-4.

7.3 External events connection

For 34 Series GCs, Auto-sampler and external events PCB (03-917750-01) or external events PCB

(03-917750-00 can be assembled to provide four external events relays.

The external events PCB (03-917750-02) only provides an external event control, uses for the

capillary sampling of split/splitless.

The external event PCB is mounted inside of the main unit. Please refer to Fig.2-5 for further

understanding installation and wiring.

Table 6 Maximum current of external events

Voltage of external event on TB1 Maximum current (AMP)

24VAC One event should be 2amp, maximum.

Four events are totally 2.5amp, maxiumum.

120VAC (Coming from transformer) One event should be 1amp, maximum.

Four events are totally 1amp, maxiumum.

120/240VAC (City voltage) One event should be 1amp, maximum.

Four events are totally 1amp, maximum.

7.4 Use external event as signal changeover

In exception with four A.C. external events, there is still having a common used detector changeover

relay and a common single-pole double throw relay locating on the external event PCB. The functions

CAUTION

With event 3 of connection in parallel is used for the detector channels to convert

double-pole double throw

Relay. During running, this relay can be changeover between the analog signals of detector

A and detector B. This relay is controlled by time path event. This relay also appears at

event 3.

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of their contact point are as follows:

1) J 96 Auxiliary (SPDT)

2) J 97 Chanel B input (CHAN B)

3) J 98 Output of channel A or channel B (OUTPUT)

4) J 99 Channel A input (CHAN A)

The power of the signal-pole double throw auxiliary relay (J 96. AUX) is 10W (D.C.), maxi. Current

is 0.5Amp, maximum voltage is 200V. In this method, the relay is controlled by time path event. This

relay also appears at event 4.The auxiliary relay is used to close the contact during running GC: (1)

Provide a delay start to the integrator; (2) Provide the integrator function used/not used; (3) Provide a

often close contact when using signal cable (02-001954-00). Refer to Fig.2-5 in details.

The detector relay is available to change signals between detector A and B. Details refer to Fig.2-5

local section C. It is located at the left side of the main unit (from J9 to J14). The detector relay is

controlled by time path event and always appears at event 3.

Remove instrument top cover and voltage cover, find out and detach the external event PCB.

(1) Change the voltage on wiring board TB1, refers to A in Fig.2-5. The standard voltage on TB1 is

24VAC. 24V AC socket connector on J101 (03-917841-00) has leading cable with voltage label.

Follow the following procedures a and b to change the voltage to 120V AC or to 120/240V AC. The

maximum current for every voltage is seen in the table 6.

a. Change 24V to 120VAC (coming from auto-transformer): Detach P101 connector on the

external event PC board, mount 120VAC connector with three brown wires (03-917842-00), it is fixed

by a key.

b. Change 24VACto 120/240VAC (City electricity): Detach P101 connector on the external event

PC board (details refer to A in Fig 2-5), mount 120VAC connector with three red wires

(03-017843-00), it is fixed by a key. The moment, the voltage on TB1 is 120VAC or 240VAC.

Warning

HIGH VOLTAGE PRESENT!

The instrument must be disconnected from all powers

And power connector of main unit before installing the external event PCB.

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Fig. 2-5 Wiring and installation of external event

(2) Wiring of external event: For SP34 Series GCs, Valve driver can be connected to any position of

for external events of TB1.

a: Stripped wire for connecting to TB1 should be 6mm.

b: Insert the wire into the position of the required external event, along with the right face of TB1,

tighten the inserted wire. Details refer to B in Fig. 2-5.

(3) Use the external event as signal changeover: If you want to changeover the output signal of the

integrator between the detector A and the detector B (INTEGA, 110 and INTEGB, J13), it is required

to connect the first interface cable (03-908348-02) between the detector A integrator (IN-TEGA, J10)

and A channel input (CHANA, J99) on the external event board. Connect the second interface

cable between the detector B integrator (IN-TEGB, J13) and B channel input (CHANB, J97). And

then connect a signal cable (02-001954-00) from the output of the external event board (J98) to

integrator analog input. Details refer to Fig 2-5.

24

(4) Mount the voltage cover again and make sure that a small chip on the cover has been all pressed

on the interlock switch S1 on the power supply PCB. Return the instrument top cover to the original

position.

8 Leak checking

34 Series GCs is factory leak checked and should not require initial internal checking. The leak

checking after column installation is recommended according to paragraph 8.1 or 8.2.

If, after you have connected gases, lit appropriate detectors and injected the test sample, your

chromatogram does not resemble the representative test chromatogram; refer to the

Diagnostics/Trouble-shooting section. Then, if more extensive leak checking is indicated, return to

this section to make the leak checking with the regulations stipulated.

8.1 Quick leak checking

Quick leak checking and non-contaminating way after the column installation are recommended. It is

to direct a small jet of gas which can be detected by the detector to the leak test fittings and

connections at the point to be tested, then use the detector at the maximum sensitivity to detect the gas

leakage into the system.

For example, methane for FID, SF6 or Freon 12 for ECD, carbon disulfide vapors for FPD, etc. The

response is rapid at points downstream of the column, but when testing points upstream of the column,

response time will be delayed by the elution time of the gas in the column. For long capillary column

(50 meters or over), a quicker leak test can be made by placing a drop of isopropyl alcohol or

iso-octane on the point to be tested. Bubbles indicate a leak. Correct each leak as it is found.

CAUTION

DO NOT uses soap fluid to make leak detection at any point in a

capillary system, as the fluid will penetrate and contaminate the system if

a leak is present. The column performance may be degraded and

substantial period of time may be required to achieve a clean system.

NOTE

1) Metal compression fittings are used at the bulkhead fittings ate the rear of the

instrument on the carrier gas and oxygen filters and fittings in the column oven. When

correcting leaks with these types of fittings, tighten only these fittings slightly.

Unnecessary and excessive tightening reduces the using life and cause the distortion of

ferrules and fitting seats that could lead to permanent leaks requiring hardware

replacement.

2) Viton ferrules with aluminum washers are used to make all of the pneumatic

ti t t th b lkh d d i h t d (S Fi 2 6) If th l k

25

Fig.2-6 Viton ferrule installation

8.2 Helium leak detection

Another non-contaminating way to leak test fitting and connections is to pressurize the system using

helium as the carrier gas. Point the helium detector probe at the fittings to be tested. An audible tone or

deflection of the meter needle indicates a leak, depending on the type of the helium detector used.

9 Pneumatic configurations

34 Series GCs may be equipped with digital or non-digital flow controllers. The digital flow

controllers are factory-calibrated and should require no initial calibration check. If required,

refer to paragraph 2.9.1 for future calibration of the digital flow controllers.

SP34 Series capillary GCs may have 0-4.14MPa (0-60Psi) pressure gauge. The required pneumatics

piping for each detector ordered is installed in the instrument before the delivery.

9.1 Digital flow controller

34 Series GC digital flow controller (P/N 03-917146-00) is factory calibrated to deliver flows from 0

to 100ml/min. for helium with an inlet pressure of 4.14Kpa (60Psi).Under these conditions, the digital

dial will indicate the actual flow to within ±3%. Dial indication is a factory of ten greater than the

actual flow, i.e., if the dial indicates 300, the flow is 30ml/min.

TSD H2 flow and the on-column capillary injector are equipped with a 0-10ml/min digital flow

controller (03-91146-01) for more precise flow control. For the on-column capillary injector,

0-10ml/min flow controller is factory-calibrated to deliver the flows from 0-10ml/min. for the helium

with an inlet pressure of 80Psi. Dial indication is a factory of ten greater than the actual flow. When

0-10ml/min. Flow controller is used for TSD H2 flow, the flow will be 0-11.9ml/min. for hydrogen

with an inlet pressure of 40Psig.

26

FPD air has a 0-200ml/min. digital flow controller(03-91146-02).The 0-200ml/min. flow controller is

factory-calibrated flows from 0-200ml/min. for helium with an inlet pressure of 40Psig. If the dial

indicates 900, the flow is 180ml/min.

When the digital flow controllers are to be removed, lock the dial to retain the numbers on the digital

dial, and then remove the flow controller, keeping the shaft from turning. This will keep the flow

controller calibration fairly accurate when it is again installed.

The flow controllers require several hours to stabilize when the first received by the customer. The

stabilization to specification level will occur within 48hours. When the instrument is not in use, the

flow controllers may be turned off (to zero); However, the pressure to the flow controller must be

maintained. On this occasion, the flow controller is not required to be stabilized again.

Fig. 2-7 Digital flow controller

The stability and accuracy of the inlet pressure regulator is vitally important. The flow stability

depends directly on the stability of the inlet pressure, so the inlet pressure itself must be accurate to

within 13.8Kpa (2Psig).

The digital flow controller requires a minimum pressure drop of 60Kpa (10Psi) for the specification

performance. Therefore, the column head pressure should not exceed 483Kpa (70Psi) to maintain the

calibrated flow controller. The system can be operated with higher head pressure if the inlet pressure is

raised (up to a maximum 1725Kpa (250Psi); However, the digital indicator will not indicate the true

flow rate.

Use the following procedures to calibrate the digital flow controller.

NOTE

Flow controllers that have not been pressurized for some time will

change flow significantly for several hours after the flow is resumed. This

is a function of the flow controller and the inlet pressure regulator. The

27

Calibration check

1) Turn on the instrument power with the instrument top cover in place.

2) Set the gas supply cylinder pressure to 552Kpa (80Psi) for He or 513.3 Kpa (77Psi) for N2.

3) Set the flow controller to 9 turns (900) and allow the flow controller and the pneumatics oven to stabilize

at least 4 hours before the calibration check.

4) Measure the flow downstream of the flow controller at the exit port and record it. The flow should

fall between 87.1 and 92.9ml/min.

5) If the flow is outside this range, follow the procedure below to readjust the flow controller shaft

and the dial so that the dial will indicate the actual flow. Refer to Fig.2-7.

a. Pull the controller knob straight up and off.

b. Insert a flat blade screwdriver on the shaft top to prevent the shaft from rotating.

c. Loosen the two screws to disengage the knob collar from the controller shaft, maintain the

controller shaft position.

d. With the screwdriver maintaining the controller shaft position, turn the knob collar until the digital

dial indicator reads out the measured flow.

e. Tighten the knob shaft screws and remove the screwdriver.

f. Re-install the controller knob.

6) Set the controller to one turn (100) and allow the controller to stabilize for at least ten minutes

before checking.

7) Measure the flow and record it. The flow should fall between 9.7and 10.3ml/min.

8) If the flow is outside this range, follow the procedures described above.

9) Again set the flow controller to 9 turns (900) and allow it to stabilize for at least ten minutes

before checking.

10) Measure the flow and record it. The flow should fall between 87.1 and 92.9ml/min. If the actual

flow is outside this range, carefully check as follows:

a. If the inlet pressure is stable at 522Kpa ±13.6Kpa (80±2Psi) for He and 531.3Kpa ±13.6Kpa

(77±2Psi) for N2.

b. The measured flows are expressed in terms of standard conditions (21.1℃, 1 atm).

NOTE

The flow controller should always be adjusted from above the desired

set-point, without” undershoot”, to achieve the reproducibility in setting.

Also note that below one turn (a reading of 100), the actual flow may

not correct well with the dial indicated value and the indicator may

28

c. There are no leaks or clogs allowing in the system.

d. The knob collar is securely fastened around the controller shaft.

If the dial indicator still does not indicate the actual flow within ±3ml/min, the flow cartridge may be

clogged or damaged. If the situation cannot be remedied, it may be necessary to call your local dealer

for service.

9.2 Pressure Transducer Calibration

The pressure transducer should be calibrated for correct analog-to-digital converter resolution and

should also be adjusted for any zero pressure offset.

10 Setting flow rates

The instrument is delivered with carrier gas flow set at the rate established for the factory final test

procedures at the specified pressure. There should be no need to initially adjust flow rate. Return

to remainder of this paragraph only if you have the problem in achieving a representative test

chromatogram.

All gas flow rates (carrier and detector) are regulated at the pneumatics panel. The appropriate gases,

filters and regulators should be installed well before proceeding with the flow adjustments. The

desired detector and injector should also be installed, referring to the paragraph 2.6.

Air and H2 valve assemblies and make-up valves use the same type of the valve cartridges. These

cartridges are provided with 0.050” thick washers, which should be removed and re-used when a new

valve cartridge is used. Flow rates for these valve cartridges are set by the operator at the flow adjust

needle valve (interior screw) of the valve cartridge knob. The valve cartridges are color-coded for the

flow rte range and recommended gases. The table 7 lists the flow rate ranges and gives the

approximate rate of the flow per turn for each of the cartridges.

Table 7 Valve cartridge color coding and flow rate ranges

Part No. Knob color Gas Flow at full

open

Flow range & change

Ml/min.

Remark

57-000291-00 Black Air 450ml/min

(60Psig)

414Kpa

Flow range100-450

Less than 150cc/turn

23℃, Air

450ml/min

57-000291-01 Red H2 60ml/min.

(40Psig)

276Kpa

Flow range10-60

Less than15cc/turn

23℃, H2

60ml/min

57-000291-02 Green He 40ml/min Flow range15-40 23℃, He

29

(60Psig)

414Kpa

Less than15cc/turn

40ml/min

57-000291-03 Blue N2 130ml/min

(60Psig)

414Kpa

Flow range30-130

Less than25cc/turn

23℃, N2

130ml/min

57-000291-04 Red with silver

stripe

H2

200ml/min

(40Psig)

276Kpa

Flow range90-200

Less than50cc/turn

23℃, H2

200ml/min

57-917060-00 Silver On/Off only

Make-up, air and H2 valves are temperature sensitive. Turn on the instrument power with the

instrument top cover in place and allow the instrument internal air flow to stabilize the internal

temperatures.

The flow rates for air, hydrogen or the detector gas flows are set individually to avoid compounding

errors in flow rate measurement. The carrier gas flow should be turned off. The detector flames are not

lit during this procedure.

10.1 Adjustment factors of bubble flowmeter

If a check of the flow rate is performed using a bubble flowmeter, it must be adjusted for the

temperature and the pressure variations by using the following formula:

273°K + Lab tem (℃) 760mm

-------------------------------- -------------------------------------- altitude factor*

294°K Local adjusted barometer

= Bubble flow-meter reading (Its accuracy is 2-5% bubble flowmeter accuracy)

NOTE

Accuracy of the flow measurement for FID depends upon efficient

sealing of the FID tower. Refer to the Flame Ionization Detector

NOTE

The carrier gas has been flowing. Firstly set the flow to zero and

allow several minutes for the carrier gas to bleed out of the column

before beginning to set the flow rates for the air, H2 or make-up

30

* Altitude (inch) Altitude factor

1000

2000

3000

4000

5000

1.041

1.083

1.127

1.174

1.221

10.2 Detector Flow Rate Setting Procedure

The flow rates for air, hydrogen or the detector gas flows are set individually to avoid compounding

errors in flow rate measurement. The carrier gas flow should be turned off. The detector flames are not

lit during this procedure.

1) Set the inlet pressures of air, hydrogen or detector gas according to the table 3 mentioned in the

section 2-6. The gas pressures are indicated on the second stage regulator of the gas supply cylinder.

2) As shown in Fig.2-8, connect a soap bubble flowmeter (recommended P/N 96-000205-00, 0-60ml)

to the selected detector. For measuring 4.5ml/min H2 flow for the TSD, refer to the procedure in the

Thermionic Specific Detector section.

3) Force a bubble above the inlet of the flowmeter. Use a stopwatch to measure the elapsed time,

which it takes the bubble to move from zero to an appropriate volume mark. Calculate the rate in

ml/min (for accuracy, choose the volumes giving at least 10-20 seconds elapsed time).

4) Measure the flow from present valve setting.

5) Refer to the specific detector flow required (see applicable detector section of this manual), and

adjust the needle valve to approximate the required gas flow.

6) Carefully adjust the flow needle valve to obtain the desired flow rate.

CAUTION

To avoid the contamination of the detector, do not allow

the soap solution from the flowmeter to flow into the exit

Warning

EXPLOSION HAZARD

Shut off the hydrogen flow immediately after making the flow

adjustment unless the hydrogen is to be ignited. Escaping hydrogen is

31

Fig.2-8 Flow measurement configurations

11 Column installation

The column installation includes the installations of injector, glass column and metal column. The

details are described in Chapter 9.

Installation instructions for fused silica capillary columns for using spilt/spiltless capillary injector,

on-column capillary injector and MegaboreR injector are detailed in separate capillary injector

32

manuals. Refer to the appropriate manual for your injector.

On-column capillary injector 03-913921-00

Split/spiltless capillary injector 03-913922-00

MegaboreR Injector 03-913926-00

12 Installations of injector and detector

34 Series GC is shipped with the injectors and the detectors installed. NO initial installation is

required. If it is necessary to install or remove additional injectors or detectors, refer to the appriate

detector section or the separate injector manual.

13 Final installation check

Prior to running the test chromatogram, make a quick final instrument installation check as follows:

* Shipping restraints/caps

1) Column oven fan motor shipping dowel removed (Para. 2).

2) Plastics or paper caps, plugs or tie downs removed (Para.2).

* Electrical

1) Proper power cord wiring (Para. 4)

2) Correct line voltage (Para. 4).

3) Instrument cabling connections between peripheral instruments (Para.7)

* Pneumatics

1) Check cylinder and secondary stage regulator.

2) Regulators set for the recommended delivery pressures (Para 2-6 in table 3).

3) Cylinders chained or strapped for safety.

4) Required gas supplies (Ref. table 3 in Para.6).

5) Inlet gas filter/traps installed and tagged.

6) Flow rate checked and adjusted (Para. 10).

7) Connecting lines and fittings leak checked (Para. 8).

* Column

Proper column installed correctly (Ref. Column section) and leak checked (Para. 8).

*Power supply

1) Battery switch “ON” (Para. 5, Fig.2-3).

33

2) Power supply switch “ON” (Para. 4, 5, Fig.1-2).

14 Running the test chromatogram

Prior to running a chromatogram, the instrument must be installed well and all pre0operational check

made per this section of the manual. We recommended that you run a test chromatogram for each

detector installed so as to obtain a definitive indication of the instrument performance and to gain the

familiarity with routine entries and with switch locations on printed circuit boards.

Retain the initial test chromatogram as a standard of comparison for later rechecking the instrument if

the change in the detector sensitivity is suspected. If you observe no peaks or unusual peaks after the

injection, turn to the Diagnostics/Troubleshooting section for assistance.

The following procedures utilize the test column and test sample shipped with the instrument. If the

test column has been removed, re-install it to run the test chromatogram. Standard packed column is

0.5(m) 3stainless column. Sieve number inside is 100-120 mesh, OV-101HP of 5%.

Set up the test conditions and gas flow rates per table 8 and follow the appropriate procedure for each

detector installed. If more than one detector is to be checked, COMPLETE ONE CHECK BEFORE

STARTING ANOTHER. It is best to first test the FID, then any specific detector installed.

Test samples are provided for each type of the detector installed in the instrument. Additional samples

can be ordered under the following part numbers:

Non-capillary

Test sample

Part Number Compound concentration

FID 82-005048-00 300ng±1%/μl of C14,C15,C16 in iso-octane

TCD 82-005048-01 300μg±1%/μl of C14,C15,C16 in iso-octane

ECD 82-005048-02 33.0Pg±1%/μl of lindane & aldrin in iso-Octane.

FPD 82-005048-03 20.0ng±1%/μl of n-dodecanethioln tributylphosphate,

methyl parathion; 4000ng±1%/μl of n-pentadecane in

iso-octane.

TSD 82-005048-04 2.00ng±1%/μl of azobenzene, methyl parathion;

4ng±1%/μl malathion & 4.00 μg

±1%/μl C17 in iso-octane.

NOTE

Capillary injector refers to an individual manual

34

Table 8 Initial GC operating parameters

For test chromatograms with test column

FID ECD GC Configuration Table

Column temp limit

Injector temp limit

Detector temp limit

250℃

400℃

350℃

250℃

400℃

350℃

Plotter (Optional)

Initial plot speed

Zero setting

1cm/min

10%

1cm/min

10%

Recorder (Optional)

Chart speed

Zero setting

1cm/min

10%

1cm/min

10%

Gas flow rates

Carrier gas

Air 1

Air 2

Hydrogen

TCD Reference cell

N230±1ml/min

300±15ml/min

-

30±1ml/min

-

N230±1ml/min

-

-

-

-

GC bake out conditions

Column temp

Injector temp

Detector temp

Flows and flames of all gases

Work temp of thermal component

Bead current

250℃

250℃

320℃

ON

-

-

250℃

250℃

320℃

ON

-

-

35

FPD TCD TSD

250℃

400℃

300℃

250℃

400℃

350℃

250℃

400℃

350℃

1cm/min

10%

1cm/min

10%

1cm/min

10%

1cm/min

10%

1cm/min

10%

1cm/min

10%

N230±1ml/min

80±2ml/min

170±3ml/min

140±3ml/min

-

He30±1ml/min

-

-

-

(He)30±1ml/min

N230±1ml/min

175±5ml/min

-

4.5±5ml/min

-

250℃

400℃

300℃

ON

-

-

250℃

400℃

300℃

ON

280℃

-

250℃

400℃

320℃

ON

-

3.0±0.3A

FID ECD FPD TCD TSD

Noise, drift test conditions

Column

Initial column temp

Injector

Injector temp

Detector

Detector temp

Time constant

140℃

250℃

300℃

Normal

190℃

250℃

300℃

Normal

180℃

220℃

220℃

Normal

140℃

200℃

220℃

Normal

175℃

200℃

300℃

Normal

Attenuation

Measure range

TCD filament temp

TCD filament current

TCD background balance

TSD bead current in Amps

1

10-12

-

-

-

-

2

1

-

-

-

-

4(P)/8(S)

10-10

-

-

-

-

1

0.05mV

270±20℃

200±10mA

＜±5Ma

-

1

10-12

-

-

-

3.0±0.3A

Sensitivity test conditions

Column

Initial column temp

Injector

Injector temp

Detector

Detector temp

140℃

250℃

300℃

190℃

250℃

300℃

180℃

220℃

220℃

140℃

200℃

220℃

175℃

200℃

300℃

36

Time constant

Attenuation

Measure range

Auto-zero

TCD filament temp

TCD filament current

TCD polarity positive

TSD bead current in Amps

Normal

8

10-10

YES

-

-

-

-

Normal

16

10

YES

-

-

-

-

Normal

64(P)/8(S)

10-10

YES

-

-

-

Normal

2

0.5mV

YES

270±10℃

200±10mA

YES

-

Normal

64-256

10-12

YES

-

-

-

3.0±0.3A

If the test chromatograms do not resemble the corresponding representative chromatograms in Figures

2-9 to 2-13, continue to Diagnostics/Troubleshooting. Check all possible causes in the

troubleshooting tables and locate any symptom on your test chromatogram. Call your local dealer for

service.

14.1 FID test chromatogram

1) Set up the instrument test conditions and the gas flow rates per table 8 and adjustment method.

Back-out instrument per the conditions outlined in table 8.

2) Ignite the FID flame by pressing [IGNITE] A or [SHIFT] [IGNITE B].

3) Allow GC to condition overnight.

4) FID Noise and Drift Check: Set the conditions per noise and drift test conditions of table 8. Let

GC equilibrate for at least one hour. Turn the auto-zero on. Set printer/plotter offset to 50%.Press the

automatic start switch, which turns the auto-zero OFF and advances GC to RUN.

Record 30minutes of baseline, then record the noise. The noise must be 2% or less at 1 X 10-12. The

drift should be less than 1% of chart width per minute.

5) If the detector passes the noise and drift tests, continue with the response check. If these noise and

drift tests were not passed, perform an additional overnight instrument bake-out, using the conditions

in Table 8, or refer to the Diagnostics/Troubleshooting section for additional information.

6) Set the test conditions per Table 8, if the conditions were changed.

7) Allow the GC to stabilize for at least 30 minutes.

8) Inject 1.0μl of the FID Test Sample. Refer to the appropriate injector manual for recommended

injection techniques. The injection automatically disables Auto-zero and advances the GC to RUN.

9) Monitor the response to the printer/plotter or the chart recorder. If C14, the first peak after the

solvent peak, did not elute at 1 +/- 0.2 minutes, readjust the column temperature (lower if C14 retention

time is under 0.8 minutes) and repeat steps 8 and 9.

NOTE

If no test sample is provided, prepare it by yourself referring to

d t ti b ti d

NOTE

The specified range and attenuation settings for the FID

have been established empirically to provide the optimum

signal to be printer/plotter. The response checks are also

dependent upon these values and will be incorrect if other

37

10) Observe the chromatogram for peak separation, peak heights, and retention times. For C14

(tetradecane, peak 1), records the peak Height (H) in % of full scale deflection. The peak height of C14

should be 25% or greater than full scale. Retention time of C14 should be 0.8 to 1.2 minutes. See

Figure 2-9.

With the completion of a successful chromatogram with the test column and the test sample, the GC is

ready for the operation. Remove the test column and install a column of your choice. If necessary, leak

check is made per the paragraph. 8, and then set up the instrument operating parameters per your

requirements.

Fig.2-9 FID Representative test chromatogram

14.2 ECD Test Chromatogram

1) Set up the instrument test conditions and the gas flow rates per Table8. Bake-out instrument per the

conditions outlined in Table 8.

2) Allow GC to the condition overnight.

3) ECD Noise and Drift Check: Set the conditions per Noise and Drift Check Conditions of Table 8.

Set the printer/plotter or the chart recorder conditions. Let GC equilibrate for at least 1 hour.

Record the baseline for 30 minutes and observe the detector output signal for the noise and the drift.

Record the noise value in percent (%). Noise (peak-to-peak signal excursion) should be 3% or less and

the drift should be ≤30% of the chart width in 30 minutes at 2 ×1.

4) If the detector passes the noise and drift tests, continue with the sensitivity check. If the noise and

the drift tests were not passed, perform an additional overnight instrument bake-out, using the

conditions in Table 8 or refer to the Diagnostics/Troubleshooting section for the additional

information.

a. If the system has excessive drift, check for air leaks.

b. If the system has excessive noise, check the electrical connections to the chart recorder. If the

noise persists for a long time, cool the oven. Disconnect the column from ECD, and cap the ECD

inlets. Check glass wool plug on the column visually. If the plug is not present, replace the column.

Connect the column to the injector but not the detector, and cap the column to the detector connection.

Set the oven temperature to 240℃ and detector temperature to 350℃. Leave for at least 4 hours, then

38

cool the oven to 50℃, reconnect the column to the detector and repeat step 3).

Refer to the Diagnostics/Troubleshooting section for the additional information.

5) Set the test conditions per Table 8, if the conditions were changed.


7) Inject 1.0 μl of the ECD Test Sample. Refer to the appropriate injector manual for the

recommended injection techniques. Injection automatically disables Auto-zero and advances the GC

to RUN.

8) Monitor the response on the printer/plotter or on the chart recorder. Observe the chromatogram for

the peak separation, peak heights, and retention times. See Figure 2-10. The following specifications

should be met:

Retention Time: Lindane peak must elute at 2 +/- 0.1 minute

Minimum detection quantity (MDQ) < 0.1 pg or

Lindane Peak Height* Noise

>13% 1.5%

>17% 2%

>21% 2.5%

>25% 3%

* Full scale (%) of chart recorder is 1mV.

Fig. 2-10 ECD representative test chromatogram

With the completion of a successful chromatogram with the test column and test sample, the GC is

ready for the operation. Remove the test column and install a column of your choice. If necessary,

make leak checking per paragraph. 8 and then set up the instrument operating parameters per your

requirements.

14.3 FPD Test Chromatogram

1) Set up the instrument test conditions and the gas flow rates per Table 8. Bake-out instrument per the

conditions outlined in Table 8.

NOTE

Perform the phosphorus mode determination first, when

performing FPD operation/response checks.

The phosphorus-mode filter (P/N 03-905948-01) is shipped in

the detector and must be in place for this determination. If it

h b h d f ll h O i l Fil Ch i d

39

2) Ignite the FPD flames by pressing [IGNITE A] or [SHIFT][IGNITE B].

3) Allow the GC to condition overnight.

* Phosphorus Determination

1) FID Noise and Drift Check for Phosphorus Determination: Set the conditions per Noise and

Drift Check Conditions of Table 8. Set the printer/plotter or the chart recorder conditions. Let GC

equilibrate for at least 1 hour. Turn Auto-zero OFF and observe the detector output signal for the drift.

If the drift is more than 1% of the chart width per minute, allow more time for the detector to stabilize.

Once the baseline has stabilized, adjust the photomultiplier tube voltage (R36 on the FPD PCB) to

give a noise level between 1 and 2% at 4 × 10-10. Adjustment accuracy is achieved by monitoring

the FPD voltage display (FPD x xxx VOLTS) in the detector Status section. This adjustment will

compensate for variations in transmission between individual filters.



in Table 8, or refer to the Diagnostics/Troubleshooting section for the additional information.

3) Set the test conditions per Table 8 if the conditions were changed.


5) Inject 1.0μl of the FPD Test Sample. Refer to the appropriate injector manual for recommended

injection techniques. Injection automatically disables Auto-zero and advances the GC to RUN.

6) Monitor the response on the printer/plotter or the chart recorder. Adjust the column temperature

such that the tributylphosphate peak (see Figure 2-11a) elutes at 1 +/- 0.2 minutes. Readjust the

column temperature if the retention time is out of the range (lower if time is under 0.8 minutes) and

repeat the adjustment of the column temperature by steps 5 and 6.

7) Observe the chromatogram for peak separation, peak height, and retention times. Following the

solvent peak, the chromatogram will exhibit two sample peaks corresponding to tributylphosphate and

methyl parathion.

For tributylphsphate (peak 1), record the peak Height (H) in % of full-scale deflection. The peak

height of tributylphosphate should be 60% of full scale at attenuation 64, with noise of 6% at

attenuation 1 and range at 10-10A. See Figure 2-11a.



check per paragraph. 2.8 and then set up the instrument operating parameters per your requirements.

Refer to the Quick Reference Manual for a summary of running a chromatogram.

40

Fig 2-11a FPD representative chromatogram (P)

* Sulfur Determination

1) Turn off the detector in GC Configure table (turns off the detector high voltage). Remove the

instrument top covers and the phosphorus-mode filter. Install the sulfur-mode filter. (Reference

Optical Filter Changing in the FPD detector section.) Replace the instrument top covers and turn

detector ON.

2) FPD Noise and Drift Check for Sulfur Determination: Set the conditions per Noise and Drift

Check of Table 8. Set the printer/plotter or the chart recorder conditions. Let GC equilibrate for at

least 1 hour. Turn Auto-zero OFF and observe the detector output signal for drift. If the drift is more

than 1% of chart width per minute, allow more time for the detector to stabilize.

Once the baseline has stabilized adjust the photomultiplier tube voltage (R36 on the FPD PCB) to give

a noise level of 1% at attenuation 8. Adjustment accuracy is achieved by monitoring the FPD voltage

display (FPD x xxx VOLTS) in the “detector Status” section. This adjustment will compensate for

variations in transmission between individual filters.



in Table 8, or refer to the Diagnostics/Troubleshooting section for the additional information.

4) Set the test conditions per Table 8 if the conditions were changed.


6) Inject 1.0μl of the FPD Test Sample. Refer to the appropriate injector manual for the recommended


7) Monitor the response on the printer/plotter or the chart recorder. Observe the chromatogram for

peak separation, peak heights, and retention times. Following the solvent peak, the chromatogram will

exhibit two peaks, corresponding to n-pentadecane, n-dodecanethiol, and methyl parathion.

For methyl parathion (the last peak), record the peak Height (H) in % of full scale deflection. The peak

height of methyl parathion should be 8% of full scale at attenuation 8. Retention time of methyl

parathion should be 2.3 to 2.5 minutes. If the retention time is not within this range, readjust the

column temperature (lower if under 2.3 minutes) and repeat steps 6 and 7. See Figure 2-11b.

Record the peak Height (H) of pentadecane (peak 1). Peak height should be less than 33% of the peak

height of dodecanethiol.

41

Fig.2-11b FPD representative test chromatogram (S)

Within the completion of a successful chromatogram with the test column and the test sample, the GC

is ready for the operation. Remove the test column and install a column of your choice. If necessary,

leak check per paragraph 8 and then set up the instrument operating parameters per your requirements.

14.4 TCD Test Chromatogram

1) Set up the instrument test conditions and gas flow rates per Table 8. Set the flows before raising

detector temperature. Bake-out instrument per the conditions outlined in Table 8. Allow GC to

condition overnight.

2) TCD Noise Check: Set the conditions per Noise and Drift Check Conditions of Table 8. Set the

printer/plotter or the chart recorder conditions. Let GC equilibrate for at least 1 hour. Adjust the TCD

Coarse Zero Balance (TCD Balance knob on TCD PCB) to give the background current to within +/-

5 mV. Adjust zero offset to place the plotter or the recorder pen near 50%. Observe the detector output

signal for the drift. If the drift is more than 1% (of chart width) per minute, allow more time for the

detector to stabilize.

Record the baseline for 15 minutes. The noise must be less than or equal to 2% at full scale (1 mV). If

the detector passes the noise test, continue with the response check. If the noise test was not passed,

perform an instrument bake-out using the conditions outlined in Table 8 or refer to the

Diagnostic/Troubleshooting section for the additional information.

3) Set the test conditions per Table 8, if the conditions were changed. Set the printer/plotter or the

chart recorder conditions. Allow the GC to stabilize for at least 30 minutes.

4) Adjust filament temperature to obtain a filament current of 200 +/- 10mA. Allow 2 hours or more

for the detector to stabilize.

5) TCD Drift Check: Turn Auto-zero OFF. Observe the detector output signal for the baseline drift. If

the drift is more than 1% (of chart width) per minute, allow additional time for thermal stabilization of

the ionization oven and filaments.

6) Adjust the zero offset to 10% of full scale. Turn Auto-zero ON.

7) Inject 1.0 μl of the TCD Test Sample.

8) Monitor the response on the printer/plotter or the chart recorder. If the first peak after the solvent

peak did not elute at 1± 0.2 minutes, re-adjust the column temperature (reduce the column temperature

if it is eluted under 0.8 minutes and repeat step 7).

9) Observe the chromatogram for peak separation, peak heights, and retention times. For C14

42

(tetradecane, peak 1), record the peak Height (H) in % of full-scale deflection and the filament current

(I) in mA. Retention time for C14 should be 0.8 to 1.2 minutes. When the measuring range is

16 0.05mV. C14 peak height should be at least 50%. See Figure 2-12.

Fig. 2-12 TCD representative test chromatogram



check per paragraph.2.8, and then set up the instrument operating parameters per your requirements.

14.5 TSD Test Chromatogram

1) Set up the instrument test conditions and the carrier gas and the air flows per Table 8. Set the

hydrogen flow for the TSD using the high resolution digital flow controller. Bake-out instrument per

the conditions outlined in Table 8

2) TSD Noise and Drift Check: Set Noise and Drift Check Conditions per Table 8. Set the

printer/plotter or the chart recorder conditions. Let TSD stabilize for more than 30 minutes. Adjust

zero offset to place plot or recorder pen near 50% full scale.

Observe the detector output signal for drift. If drift is more than 1% (of chart width) per minute, allow

more time for the detector to stabilize. Record the baseline for 15 minutes. The noise level of the

detector should be less than 2% (peak to peak value).


drift tests were not passed, perform an additional overnight instrument bake-out using the conditions

in Table 8, or refer to the Diagnostics/Troubleshooting section for additional information.

4) Set the test conditions per Table8, if the conditions were changed. Allow the GC to stabilize for at

least 30 minutes.

5) Set the bead current to 3.4mA. A positive rise of the background signal should be observed.

6) Auto-zero adjustment makes the background current reaching 10% of the chart recorder or the

printer/plotter.

NOTE

Flow rate setting for the TSD is critical. Hydrogen flow accuracy

must be within 4.5 +1/-0 cc/min and should be made using only the

bubble flowmeter (96-000205-00). Allow at least 30 minutes for

43

7) Inject 1.0μl of the TSD test sample. Refer to the appropriate injector manual for recommended


8) Monitor the response on the printer/plotter or the chart recorder. Reset the GC and reduce the bead

current at 0.1A per step with an injection of 1.0μl of the test sample after the bead temperature is

stabilized (about 10 to 15 minutes).

9) Repeat step 8 until the bead current setting meets the following sensitivity and selectivity

specifications, i.e., C17 peak height < 25% azobenzene peak height at 32 × 10-12 A/mV. A typical test

chromatogram, as shown in Figure 15, should be obtained.

Azobenzene peak height: > 25% at 32 × 10-12 A/mV full scale

Malathion peak height: > 40% at 32 × 10-12 A/mV full scale


ready for operation. Remove the test column and install a column of your choice. If necessary, leak

check per para. 8, then set up the instrument operating parameters per you requirements. Refer to the

Quick Reference Manual for a summary of running a chromatogram.

Fig 2-13 TSD representative test chromatogram

44

SECTION THREE OPERATION

1 Instrument keyboard description and use

Figure 3-1 shows SP34 Series GC instrument keyboards with all options and a brief functional

description of each keyboard section. Whenever the instrument is ON, the one line display above the

keyboard presents the information. Lights on the keyboard are used to indicate the various working

states of the instrument.

The keyboard has keys for the maximum number of options available. Each press of a key will

sound a “beep,” indicating keyboard recognition and, the most keys can change the display. Only

those options you have will be functional on your instrument.

Some keys have a second function, as indicate by an orange label below the key. To access this second

function simply press [SHIFT] (also labeled in orange) and then the appropriate orange labeled key.

The basic functions of each GC key are described in Figures 3 through 9. DISPLAY CONTROL keys

may be used for quick access to previous displays or the next logical display. Refer to Figure 6 for

detailed use of the DISPLAY CONTROL keys. Use these figures 3-1 through 3-8 for future review of

all keys.

45

B

COL OVEN

START

START

NOT REMOTE

RUN READY

DET-A

PLOTTER

ATTENUATIO

RESET

IGNITE GC

OFF

FEED

STOP

ZERO

DET-B

GC CONTROL

BUILD/MODI

STATUS

ACTIVATE COPY

LOCK/UNLO

DELETE

DELETE TUNE ONPRINT

REPORT

ACTIVE

SECTION

METHOD 1 METHOD 2 METHOD 3 METHOD 4

INJECTOR

AUTOSAM

COLUMN DETECTOR

PLOTTER REPLAY

RACK

SUSPEND

SEQUENCE

SUSPEND

OPERATION

METHODS

DISPLAY CONTROL

0

OFF

-

TUNE/IN

1

SINGLE

2

MULT

3

4

YES

5

NO

6

7

A

8

B

9 CE

ENTER

OPERATIONS

SHIFT PROM

HELP

AUTOMATION CONTROL

Use these keys to select one of

the two automation tables. The

lights indicate if a table is active

or inactive or if a table entry is

being displayed

The display presents information and

is always active

These keys provide a variety of

instrument control functions.

The lights in this section show the

state of the instrument and

whether it is under remote control

by an external data system.

Use these keys to

initiate GC functions.

The lights indicate the

mode, BUILD/MODIFY

or STATUS

Use SHIFT to access the

second (orange) function

of dual function keys.

Use the DISPLAY CONTROL

keys for quick movement

through methods and tables.

(Refer to Figure 6 for use of

these keys.)

PROMPT

Press and hold PROMPT to display

legal ranges for values that may be

entered for the current display.

HELP

Press SHIFT then hold HELP to

display a number reference in the

HELP section of this manual where

additional information about the

current display is located

Use the METHOD keys to

select the method wanted.

Inactive as well as active

methods can be examined and

modified. The light by the

currently displayed method is

ON.

Use the SECTION CONTROL

keys to select the method

section wanted

ENTER must be pressed to

complete an entry. ENTER also

advances the display. When keys

have more than one label, the entry

expected by the instrument is

accepted

46

Fig. 3-1 SP34 Series Keyboard Function Description

Press [SHIFT] key to select the second function of dual function keys

(Labeled I orange)

Fig. 3-1 SP34 Series GC Control keys

START

Press to immediately start GC run. Starts automation and Auto-sampler when GC READY.

READY and NOT READY Lights

Light is ON if GC is READY or NOT READY for injection. See the section 3.6 for instrument status.

GC CONFIGURE

Automatically sets GC in BULID mode. Press to access a table of the instrument control parameters

that are not part of the methods.

(SHIFT) INSTR TEST

Press to access instrument test function. If GC is in RUN or if an automation table is active, the

47

instrument test mode cannot be accessed. Refer to the Diagnostics/Troubling shooting section for

detailed used.

IGNITE A and (SHIFT) IGNITE B

Press and hold to power detector A or B igniter coil for FID and FPD. Igniter times our after 10

seconds.

(PLOTTER) START

Press to start the plotter.

(SHIFT) FEED PAPER

Press and hold to feed the plotter paper. When loading paper, paper runs for 2 minutes after pressing

FEED PAPER.

ATTENUATION

Each keystroke raises or lowers plotter and recorder attenuation by a factor of two for A or B

detectors.

(PLOTTER) STOP

Press to stop printing or plotting.

(SHIFT) ZERO PEN*

Press to shift plot from the current location to zero offset value on the plotter.

Fig. 3-3 GC Control keys

COL OVEN ON & (SHIFT) COL OVEN OFF

Use to turn column oven heater and fan ON/OFF. If cryogenics installed, enables or disables coolant.

REMOTE CONTROL Light

It is ON whenever GC under series controls of remote computer such VISTA Chromatography Data

System.

48

RUN Light

It is ON only GC in run.

RESET

Press to end run, stop Auto-sampler and automation operation, and restore initial conditions of active

method.

BUILD/MODIFY Key & Light

The indication light comes ON when key is pressed. Entries can be made into all methods, GC

configure table and automation table when light is ON.

(SHIFT) ACTIVE LINE

Press to display the method program presently in progress. The BUILD light comes ON. Allow quick

real time updates to active method.

ACTIVATE

Activate a method (METHOD 1, 2, 3, or 4) or automation table (RACK or SEQUENCE) to check for

completeness. Refer to the section 3.4, activating a method.

Copy

Use to copy one method to another. Copy action is prohibited if the method is locked, The copy can be

made from a running method.

(SHIFT) LOCK/UNLOCK

Use to lock or unlock individual methods or tables via numerical code entry. The code is user-set in

GC configure table.

DELETE PROGRAM

Use to delete temperature, time or automation PRGM’s.

DELETE SECTION/TABLE

Use to (1) Delete optional method section or automation tables, or (2) restore required method

sections to preset with single keystroke. (3) Delete all PRGM’s built with the selected method section

or table.

Methods 1, 2, 3 and 4 keys and lights If BUILD/MODIFY light is ON, all

Press to select the method to control the 4 methods can be examined and modi-

instrument as specified by an operations fied. If STATUS light is ON, each

key. Light is ON whenever method is being section displays only the current set

monitored or built. Point and actual information for the

active method. (The light by the

active method is ON)

49

FIG.

REQUIRED METHOD SECTIONS

Column

Use to select/control

Injector

Use to select

Detector

Use to select detector A or

detector B control of

⊙Column oven temperature ⊙Injector temperature ⊙Detector temperature

⊙4 temperature program ramps ⊙ 2 temperature program

ramps

⊙ Recorder and plotter

attenuation

⊙Optional pressure setpoint ⊙Temperature control and

programming of auxiliary

zone

⊙Range

⊙Auto-zero

⊙ Data System channel

select (A or B)

⊙ Entries specific to each

detector

⊙Up to 5 time programs per

detector to control functions

during the run

OPTIONAL METHOD SEIONS

Plotter

Use to select/control:

Auto-sampler


Relay


Plot speed VISTA Auto-sampler Time-programmed relays

during run

Zero offset Sampling mode: OFF,

SINLE, MULTI

AC power switches to

operate sampling valves or

capillary splitter vent

Plot signal A or B Number of injections per

vial.

Signal selection of detector A

or B

50

Enable time ticks Sample volume Low level contact closure

Plot annotations Number of purge times Up to 20 time programs

Printing run log at run end ⊙Injection time

Up to 5 times programs for

changing plot speed and signal

A or B during run

⊙Time sampling start

TURN ON

Tune mode allows user to immediately execute any time-programmable programs and simultaneously

enter execution time into method during run.

PRINT (Only using for the plotter installed)

Initiates printing of methods, sections of methods, or tables.

(SHIFT) REPORT (Only using for the plotter installed)

Press to print report and run log for current run.

STATUS Key and Light

Press STATUS to monitor the current instrument parameters. The Status light and method light for the

active method or automation table comes ON. No entries are allowed.

Press ENTER to advance through STATUS displays. Press specific SECTION CONTROL or

AUTOMATION CONTROL keys for more Status displays. Light blinks if the instrument appears

error. Refer to the section 3.5.

Fig. 3-4 Method and section control

51

DISPLAY CONTROL keys provide quick access in method sections and tables. In this manual, these

keys will be referred to as back ( ), forward ( ), PRGM back (▲), and PRGM forward (▼).

Press ( ) to advance to the next display in a section or table.

Press ( ) to reverse to the previous display.

Press( ) at the beginning of a section loops to the end of that section. Use these keys to quick loop

forward or back through the displays in a given section or table. (Press the appropriate SECTION key

to advance to another section).

(▲) and (▼) are used within PRGM lines only. (▲) and (▼) loop at the first and last display within

a PRGM.

NOTE: The “ADD” displays (i.e. ADD NEXT COLUMN PROGRAM? NO, etc) are only seen

when advancing forward through the displays and only when no following programs have been added.

Pressing ( ) when this line is Pressing ( ) when this PRGM is displayed

Displayed moves forward to: loops back to:

TEM PROGRAM COLUMN/ NO PRGM 4 COL RATE IN°/MIN

INITIAL COL TEMP 50

INITIAL COL HOLD TIME

TEMP PROGRAM COLUMN? NO (PRESS YES ENTER TO BUILD PRGMS)

PRMG 1 FINAL COL TEM PRGM 1 COL RATE IN°/MIN PRGM 1 COL HOLD TIME


PRMG 3FINAL COL TEM PRGM 3 COL RATE IN°/MIN PRGM 3 COL HOLD TIME


Pressing ▼ when this line is Pressing ( ) when this line is

Displayed loops back to: displayed loops back to:

PRGM 1 FINAL COL TEMP INITIAL COL TEMP 50

52

Fig. 3-5 Use of display control keys

NOTE: Press SHIFT to access the second (orange labeled ) function of double

Function keys.

Fig. 3-6 Automation control keys

� RACK TABLE

Us for Auto-sampler (A/B) automation operation. Entries are rack numbers and associated method

numbers. Only one method can be assigned to a specific rack number ; however, one method can be

run on several racks.

Light is ON whenever method is being monitored or built.

② SEQUENCE TABLE

Use with an auto-sampler (A/B) or sampling valves.

This table lists methods in the order to be executed by the automation. Specific number

of times to run each method.

Light is ON whenever method is being monitored or built.

(SHIFT) (RACK TABLE OR SEQUENCE TABLE) SUSPEND

53

Press to suspend automation at end of current action.

Press START to resume the automation.

Fig. 3-9 Entry keys

� ENTRY KEYS

When a number key also has a word/letter beneath it, the appropriate response is recognized by the

instrument. Displayed prompts inform the user of word or number choices.

None of the Entry leys are used with SHIFT.

� CE (CLEAR ENTRY)

Press to clear the parameter vaue from entry field.

� ENTER

Use to accept the entered values and move to the next display. The tests are performed on the entered

values and , if an entry is illegal, the display informs the user.

If an entry is not completed by pressing ENTER, the previous ntry is retained.

Pressing ENTER advances to the nest display and, following the last display of a section, advances to

the next section. Pressing ENTER for the last display of the last method section displays METHOD

COMPLETE—END TIME XXXXX.

54

2 RUNNING A CHROMATOGRAM

Running a chromatogram on 34 Series GCs can be summarized in the form of a check list.

As you move through each step of the check list, a paragraph or Section reference number is provided

for rapid access to the information.

OPERATION CHECK LIST

1) Desired hardware properly installed (Installation section).

2) Desired analytical column installed (Column section), flows adjusted (Installation section), and

flames lit (FID and FPD detector sections).

3) Connections made to a chart recorder (Installation section) and/or external data system (External

Data Systems tabbed section).

4) Instrument power ON (Installation section). (Specify instrument configuration, including

temperature limits.)

5) Set up GC configure table (3.3), including instrument condition configure of temperature limit.

6) Build the desired method (3.4).

a. Press BUILD/MODIFY.

b. Press appropriate METHOD key (METHOD 1, 2, 3, or 4).

c. Build the COLUMN, INJECTOR, and DETECTOR method sections (ref. 3.4).

d. Build desired optional method sections if hardware presents: PLOTTER, AUTOSAMPLER, or

RELAYS.

7) Set up pneumatic valve programmable table

a. Press SEQUENCE TABLE key, advances to display.

8) OPERATION CHECK LIST

a. Check instrument Status (Operation section) by pressing STATUS. Press [ENTER] to view

additional messages.

b. If a temperature is out of tolerance, the degree symbol for display flashes and the “NOT READY”

light is ON (Operation section).

c. A blinking STATUS light indicates an instrument fault. Press STATUS key (Operation section) to

display the fault. Press ENTER key to display any additional faults and instrument status information.

See the Diagnostics section to diagnose faults.

NOTE

When building/editing methods:

1. Follow the displays.

2. View legal entries for displays by pressing PROMPT.

3 Press SHIFT HELP for a number reference to the HELP

55

9) Active the method (Operation section).

a. Press ACTIVATE, then the method key (Method 1, 2, 3, or 4).

10) Inject the sample when the READY light comes ON (Operation section).

11) Automated operation check list

a. To run sequence automation, build SEQUENCE TABLE (Automation Control) by pressing BUILD

SEQUANCE TABLE. (Optional)

b. Press RACK TABLE key to display:

c. Set up programmable table (Optional), use for auto-control of the auto-sampler. (3.4)

d. Press SEQUENCE TABLE key, display:

12) Press START to start the automation.

3 SETTING UP THE GC CONFIGURE TABLE

Prior to method building, you will need to set up your instrument configuration via the GC

configure table. This table allows access to a variety of the instrument control parameters, among

them, setting time and date, temperature limits and checks for GC READY.

Access or bypass categories by entering YES or NO.

EXERCISE

1) Switch on the power supply located at the back of GC instrument. See Fig.1-2.

2) Press BUILD/MODIFY GC CONFIGURE to display:

SET TIMES OR DATE/ NO

3) Press YES ENTER to display:

THERMAL STABILIZE TIME 2.00

Enter your desired stabilization time or press ENTER to accept the preset of 2.00 minutes.

NOTE

If you feel the prompt does not fully explain the

parameter in question, press SHIFT and Hold HELP

to display a number in the HELP section of this

manual, which explains use of the parameter or gives

NOTE

Pressing ENTER in response to SET TIMES

OR DATE? NO will bypass the times and date

56

4) Display advances to:

ENTER TIME OF DAY AS HHMM XXXX

This is a 24-hour clock, so, if it is 2:25 in the afternoon, you would press [|1|4|2|5| ENTER]. Enter the

present time of day.


ENTER DATE-DAY MONTH YEAR 050384

Enter the present day and month as a 6-digit number without punctuation.

6) Display: COOLANT TIME-OUT MIN INF

Enter the desired coolant time-out (shut off time after GC READY) or ignore if the coolant is not

being used.

7) Continue to enter GC configuration conditions, press [ENTER] key to accept presetting. When it is

required, press [PROMPT] or [HELP] key.

When displaying the following:

SET TEMP LIMITS/ NO

Press [YES] [ENTER.]


COLUMN TEMP LIMIT 250

Enter the upper temperature limit for the column you have installed.


INJECTOR TEMP LIMIT 250

Enter the upper temperature limit for the injector you have installed.


DETECTOR TEMP LIMIT 300

Enter the upper temperature limit for the detector you have installed.


AUXILIARY TEMP LIMIT 52

If you will be using an auxiliary temperature zone, such as a sampling valve, enter the upper

temperature limit for that zone.

IMPORTANT NOTE

Methods cannot be built with COLUMN, INJECTOR,

DETECTOR, or INJ B temperatures set higher than they

entry for this display.

Reset the column temperature limit each time you change

57

If you do not have an auxiliary zone, press [ENTER] to advance to the next.

12) Continue to enter the GC conditions. Go to the next section when followings appear.

GC CONFIGURE TABLE COMPLETE

4 METHOD BUILDING

A method is the set of conditions required to run the GC in performing an analysis. Four methods are

always present in 34 Series GCs.

When powering up, Methods 1 through 4 are identical minimum methods, containing presetting value

entries in the required method sections (COLUMN, INJECTOR, and DETECTOR). Minimum

methods will rarely be suitable for use, but through method modifying, more sophisticated methods

may be built to suit your particular requirements.

4.1 Building a Basic Method

The following exercise will provide hands-on experience in building a basic method. Use this exercise

for either isothermal or temperature programmed operation of the column oven. The display will guide

you in making entries or correcting errors.

For detailed descriptions of each display and the intended chromatographic use, press [SHIFT] [HELP]

and refer to the referenced number in the HELP section.

EXERCISE

1) Press [BUILD/MODIFY] key, BUILD light goes ON and the display instructs you to

SELECT METHOD OR TABLE

COLUMN Section

2) Press [METHOD 1] key. METHOD 1 light goes ON.

Display: INITIAL COLUMN TEMP 50

3) Enter the initial column temperature for your analysis.

4) Continue through the COLUMN displays, entering values for your analysis.

When you see the following display,

TEMP PROGRAM COLUMN? NO

a. Press [YES] [ENTER] keys to select temperature programming if the temperature programming is

required

b. Press [ENTER] key if the isothermal operation is desired, and move to the first display of the

INJECTOR section.

INJECTOR Section

5) Press [BUILD/MODIFYD][METHOD1][INJECTOR] keys, display to:

INJECTOR TEMP 50

58

6) Enter an injector temperature for your application. This is the only available entry for standard

(STD) injectors. The display will move to the first display of the DETECTOR SECTION.

7) The on-column capillary injector (OCI) has additional injector displays for temperature

programming. Enter the required values for your analysis. Be sure you have set switch S2 on the

Temperature Control PC Board to OCI. When appearing the above display, that shows that the first

display of DETECTOR SECTION is reached.

DETECTOR Section

8) Detector displays vary depending on the type and number of detectors installed. Enter a detector

temperature for your application.

9) Advance through the DETECTOR display by setting all values for your detector.

When appearing any of the followings, continue building a, b, c or d:

METHOD COMPLETE – END TIME XXXX (See a)

ADD PLOTTER SECTION? NO (See b)

ADD AUTOSAMPLER SECTION? NO (See c)

ADD RELAY SECTION? (See d)

a. If any of the option parts are installed on the instrument, the first display above-mentioned is the

end display of the detector section. Move to Method Start.

b. If the plotter is installed, continue to process the item 10.

c. If the auto sampler is installed, continue tp process section 3.4.2.

d. If the relay is installed, continue to process section 3.4.3.

PLOTTER section:

10) Press [YES] [ENTER], add the plotter section to Method 1.

11) Continue to display by the plotter, enter the values required.

When all method sections have been built, the last display is

METHOD COMPLETE—END TIME XXXXX

4.2 Use auto-tables to set up method

If no auto-sampler is used, use the relay to set up the method.

RACK TABLE or SEQUENCE TABLE can be allowed to run with the instrument together. The

instrument is controlled by RACK TABLE (RACK Drive) or SEQUENCE TABLE METHOD Drive).

RACK AUTO-TABLE can be only used for the auto-sampler injection, but the SEQUENCE

AUTO-TABLE can be used both with the auto-sampler or without the auto-sampler. If there is no

auto-sampler installed, the SEQUENCE AUTO-TABLE can be used to control a pneumatic valve.

59

The following exercise includes the auto-sampler section and auto-table.

4.2.1 Setting up auto-sampler section

If Rack table or Sequence auto-sampler is used, the autosampler section should be set up.

If using SEQUENCE TABLE, it onle control the pneumatic valve.

EXERICE:

1) Press [BUILD/MODIFY][METHOD 1][AUTOSAMPLER], display to:

ADD AUTOSAMPLER SECTION? NO

2) Press [YES][ENTER].

3) Enter all required operation mode. Remember to use PROMPT or HELP key.

4) Continue to enter the required values by Rack display.

When appearing any of the followings:

ADD RELAY SECTION? NO

Or METHOD COMPLETE – END TIME XXXXX

The auto-sampler section is set up.

a. If the method does not require RACK or SEQUENCE TABLE, continue to process the section 3.4.3.

Set up the method with relay.

b. A RACK or SEQUENCE TABLE is required for the auto-sampler. The next section is to set up the

RACK TABLE, while set up the SEQUENCE TABLE in the section 3.4.3.

4.2.2 Setting up auto-controlled rack table

On this occasion, the instrument is droved by RACK, instead of SEQUENCE Drive.

EXERICE:

1) Press [BUILD/MODIFY][METHOD 1][RACK TABLE], display to:

PRGM NUSE RACK NIMBER XXX

2) Continue to enter the required value by RACK TABLE display. When “ADD” to enter the next

PRGM display, enter [YES] to continue setting up PRGMS or enter NO to display:

RACK TABLE COMPLETED

3) Continue to process the section 3.4.3 after completion, set up Method with relay.

4.2.3 Setting up auto-controlled sequence table (with Auto-sampler)

Refer to the section 2.4 for setting up the sequence table without auto-sampler.

EXERICE:

1) Press [BUILD/MODIFY][METHOD 1][SEQUENCE TABLE] display to:

60

RUNS OF TABLE? SINGLE

2) Continue to enter the required values by SEQUENCE TABLE diaplay. When “ADD” to enter the

next PRGM display, enter [YES] to continue setting up PRGMS or enter NO to display:

SEQ TABLE COMPLETED

3) The auto-controlled sequence table of the auto-sampler has been set up. Move to

the section 3.4.3, set up the method with relay.

4.2.4 Setting up auto-controlled sequence table (without Auto-sampler)

The SEQUENCE TABLE without the auto-sampler can be used to control the pneumatic valve.

1) Press [BUILD/MODIFY][METHOD 1][SEQUENCE TABLE] display to:

RUNS OF TABLE? SINGLE

2) Continue to enter the required values of controlling pneumatic valve by SEQUENCE TABLE

display. When “ADD” to enter the next PRGM display, enter [YES] to continue setting up PRGMS or

enter NO to display:

SEQ TABLE COMPLETED

The Sequence table of he controlled pneumatic valve has been et up, continue to the next section.

Setting up Method with relay

If the relays have not been installed yet or not been used any more, continue to process the section

METHOD START.

SP34 Series GC”S has provided with four relays, which are used to make the valvce automation, run

spilt/spiltless capillary injector or drive peripherals running.

EXERICE:

Relay section

1) [BUILD/MODIFY] and [METHOD 1] lights should be all lit. If it is not so, press proper key to

make it lit. The moment, press[RELAY][ENTER] keys , display to:

ADD REALY SECTION? NO

Press [YES][ENTER] keys , add the relay section to Method 1 and display to:

INITIAL REALY-1-2-3-4

Negative sign in the front of 1, 2, 3, 4 of relays is cut off, that shows the relay corresponding that

number are cut off. Press [ENTER] key, display to:

TIME PROGRAM RELAY? NO

NOTE

If one more gas sampling valve (GSV) or column sampling valves

(CSV) are existed in the system, you can use the different method

61

Press [YES][ENTER] keys , display to:

PROGRAM RELAY TIME MIN

Enter range from 0.01-650. As example as 10:

Press [1] [0] [ENTER], display to:

PRGM, RELAY-1-2-3-4

That shows programming relays, 1, 2, 3, 4 are all cut off.

Press [1] [ENTER]:

Relay 1 will be opened within 10 minutes, display to:

ADD NEXT RELAY PRGRAM? NO

Is it required to add next relay? ( this example only uses one relay, no need to add).

Press [ENTER] key, display to:

METHOD 1 COMPLETE-END XXXX

This display will be held up until another action is selected.

Before entering to the next section, check and modify the methods having set up.

3.4.4 Activating Methods and Tables

After a method or table is built, it must be activated before it can be used. The activation process

informs the instrument which method or table in memory will be used to run the next analysis and also

runs checks on the method or table. One method is always active.

If the following case occurs, method or table can not be activated.

The instrument is running.

Auto-table has been effective.

Table required has not been set up yet.

ROMOTE CONTROL light is lit.

Follow the following procedures to activate a method or table:

1) Press [ACTIVATE] key, them the method key ( METHOD 1, 2, 3, or 4) or the appropriate table

key (RACK TABLE or SEQUENCE TABLE).

2) If the selected method or table is effective, all lights selected should be lit.

a. If the method or table is ready for use, the display will be

METHOD ACTIVETED or TABLE ACTIVATED

b. If the method or table is not ready for use, the display will show the reasons (such as: METHOD

RUNNING, TABLE IS NOT BUILT, WITHOUT AUTOSAMPLER, etc).

c. Once the method or table is active, begin the automation by pressing [START] key or by making

62

a manual injection.

5 USING STATUS

When [STATUS] is pressed, the [STATUS] light goes ON, the active method light goes on, and

a) The active method and any of its method sections may be monitored;

b) A fault condition is displayed (see para. 3.5.1);

c) A NOT READY condition is displayed (see para. 3.5.1).

The display of fault conditions takes priority over other Status displays.

When [STATUS] light is ON, always displays

INSTR STATUS—NO USER ENTRY

● Monitoring the STATUS of an Inactive Method

When in the STATUS mode, another METHODS key may be pressed to display the inactive method’s

end time, such as

METHOD X INACTIVE—END TIME XXXXX

This is the only Status display for an inactive method.

● Monitoring Elapsed Run Time

If the instrument is in RUN, the Elapsed Run Time can be monitored by pressing [STATUS][ENTER]

to display

METH X RUN 1.35 END 22.00 MIN

METHOD INSTR ELAPSED METHOD END

NUMBER STATE RUN TIME TIME

If the GC is not in RUN, the RUN time displayed is 00.00.

3.5.1 Using the Blinking STATUS Light to Display Fault Messages

A blinking STATUS light indicates that the instrument has detected a fault condition. A fault condition

may result from hardware configuration mismatch, improper temperature zone, plotter paper out,

flame out, etc.

When the STATUS light is blinking, press [STATUS] to display the initial fault message. Press

[ENTER] to display additional fault message.

A fault condition should be modified. For example: repairing hardware, or enter every display with

keyboard. The display will inform of you the fault part status. Some parts may require cutting off, but

it is open during the operation. For example:

COLUMN COOLANT OFF

63

Some displays will let you look for the operation manual to find the fault, or re-set up a method.

Display example:

ILLEGAL METHOD

The above display informs you that the active method contains an illegal method section, caused by

changing the instrument configuration after the method section was built, i.e., standard injector

removed and an on-column capillary injector installed. The STATUS light blinks and the GC is held

NOT READY. Press |STATUS| |ENTER| to display the fault(s). Refer to the

Diagnostics/Troubleshooting section for a complete listing of fault message.

NOTE: Correct an illegal method by correcting the hardware configuration or deleting the illegal

method section.

3.5.2 Using STATUS to Display NOT READY Conditions

If the NOT READY light is ON, one or more NOT READY conditions exist. Press [STATUS], Two or

more displays will always be present and displayable by pressing [ENTER].

If one of the following four displays is applicable, it is displayed first.

METHOD X STABILIZE XXXXX MIN

METHOD X WAITING FOR EXT DEVICE

METHOD X A/S WAITING XXXXX MIN

METHOD X A/S SAMPLING

Press [ENTER] key and continue to display the standard STATUS of your instrument configuration, as

listed in the Displays section. A flashing symbol (°) in STATUS display indicates that the zone is out

of its set-point tolerance. Refer to para. 3.5.3, Set-point Errors.

3.5.3 Set-point Errors

Set-point errors indicate a tolerance error between the operator set value and the actual value of a

parameter. When an out-of-tolerance set-point is detected, the flash symbol(°) for that zone’s

STATUS display will flash.

Followings are the set-point errors for 34 Series GCs;

Parameter Set-point Window/Cause

Column oven temp. +/- 1.3℃

Injector oven temp. (STD) +/- 4.5℃

Injector oven temp. (on-column injector) +10℃/-40℃

Auxiliary oven temp. +/- 4.5℃

64

Detector (Ionization oven temperature +/- 2.5℃

TCD oven temperature. +/- 1.5℃

TCD filament Changeover to constant current mode

TCD Current off Bridge broken of Thermal conductivity cell

Plotter ADC Digital converter of plotter is unable to handle

with big or fast increased signal.

6 INSTRUMENT STATUS

While operating, the GC may be in one of several states. The READY, NOT READY, and RUN lights

show the GC state. Some instrument capabilities vary depending on the GC state. The following

paragraphs describe the conditions that cause the instrument to go from one state to another and what

operations may or may not be performed in these states. See Figure 3-10.

6.1 READY State

When in this state, the READY light is ON and the GC is ready for the injection. All instrument

temperatures are at their set-points, the plotter is available, and no error conditions exist.

If the auto-sampler is used, READY light is not required to be ON, but the READY light must be ON

when next period of the auto-sampler comes.

An external ready input is available on the Mother PCB for use by peripheral instruments. Refer to the

Installation section for specific cabling connections.

65

FIG.. 3-10

Sample temperature/time graph showing instrument states

6.2 NOT READY State

When the NOT READY light is ON, one or more Not Ready conditions exist. To find the problem,

press |STATUS| to display the Not Ready conditions.

For a list of set-point errors, refer to para. 3.5.3.

Not Ready can be generated for peripheral instruments by connections made on the Mother PCB.

Refer to the installation section for specific cabling connections.

6.3 STABILIZE State

The STABILIZE state is a checking period that begins after the last temperature zone checked has

come within its set-point tolerance. The THERMAL STABILIZE TIME is two minutes, unless

changed in the GC Configure table.

If any set-point goes out of tolerance before the GC goes to READY, the STABILIZE status will

restart. The NOT READY light will remain ON until temperatures stabilize, at which time the GC will

go to READY (READY light goes ON).

66

●Monitoring the Stabilization Count Down

Prior to the instrument going to READY, and after the instrument has reached its set-points, begin

from two minutes stabilized time having set, you can monitor the instrument counting down from the

stabilization time. Press [STATUS] to display

METHOD X STABILIZE 2.00 MIN

METHOD INSTR STATE STABILIZE

NUMBER COUNTDOWN TIME

NOTE

6.4 RUN State

The GC advances to RUN at injection, irrespective of READY/NOT READY conditions. The GC will

remain in RUN until method END TIME or until RESET is pressed.

Both GC READY OUTPUT and REMOTE READY INPUT are available on the Mother PCB,

allowing the GC to control remote devices. Refer to the Installation section for specific cabling

connections.

7 MODIFYING THE METHOD WITH REAL TIME UPDATES

A Real Time Update is a change entered into the currently active method. The GC may be in or out of

run. Examples are changing thermal zone temperatures or adding or modifying temperature and time

programs.

If the GC is not in RUN, changes to initial conditions for any method section which are executed

immediately if the method is active. Temperature added and modified at any time.

●Real Time Updates With the GC in RUN

A change to any line in the method requires re-computation of the END TIME. If a real time update

results in the END TIME being less than the current RUN TIME, the GC immediately resets. Real

time update changes are recorded in the Run Log with the execution time of the change listed. All

changes remain in the method except attenuation updates made via the ATTENUATION keys.

When the active method is in RUN, you may quickly display what is being executed. Real time update

entries may not be immediately executed if program steps are present. Display the currently active

program by pressing [SHIFT] [ACTIVE LINE].\

NOTE

The STABILIZE state cannot be distinguished from the NOT READY

state by looking at the GC lights. Press[STATUS] to display the

instrument state (as above). Pressing [RESET] when in the

STABILIZATION state cancels the remaining stabilization time and

67

● Modifying Temperature Programs

All parameters for column, injector, detector, and auxiliary temperature zones can be updated with real

time updates. Acceptable temperature entries are always bounded by the TEMP LIMIT values

set in the GC Configure table and by other temperature programs built in the method.

Real time updates that would decrease any temperature in a run are not executed; instead, the

temperature at the time the lower temperature was entered is maintained. A higher temperature real

time update is executed. Changes to temperature program rates and hold times are noted immediately

and can affect the run END TIME if other method sections do not require longer times.

● Modifying Time Program

The parameters in time programs for DETECTOR, PLOTTER, and RELAY method sections are

executed during the run at the run time specified by the first line of each program. Programs with an

indefinite “tune” time are not automatically executed, but are executed by the user during the run

Changes to the currently active time program line are executed immediately upon entry, such as

detector range or plot speed.

8 WARM START

The purpose of warm start is to retain methods and tables in the advent of a power failure.

1. If the battery switch (see Figure 4, Installation section) is in the ON (up) position and there is a

power failure, all methods and tables built will be retained.

2. Besides retaining the methods, warm start also returns the instrument to the same place in a PRGM

as when the power fail occurred and continues the run.

3. If running automation and the power fail was for an extended period and the thermal zones have

cooled, automation will resume when thermal zones have destabilized.

If the battery was removed or turned off, the instruments will cold start when power is turned on. All

methods and tables will be returned to their preset values. Cold starting is sometimes required when

performing diagnostic procedures. Refer to the Diagnostics/Troubleshooting section for Cold Starting

the Instrument.

68

SECTION FOUR INJECTOR

1 INSTRUCTION

This section describes Ф3, Ф6, glass and on-column injector and flash vaporization injector used for

34 Series gas chromatograph. A detailed physical description, installation instructions, and day to day

routine maintenance procedures are provided. A brief review of recommended injection techniques is

also included. In the interest of clarity, all references to “injector” will assume the injector body and

heater block assembly, unless the body or block is specifically called out

2 AUTOMATIC START SWITCH

An automatic start switch is a spring loaded actuator that fits over, and is aligned with the injection

port of the injector nut, see Figure 1-1. The GC run is started when the actuator is depressed by the

syringe barrel of pressed manually at the moment of sample injection. The GC run can be also

manually started by pressing “START” key.

3 INJECTION TECHNIQUES

For syringe sample injection, the Hamilton 700 series micro-liter syringe from United state, SGE from

Australia, or from Shanghai Injector Factory, China is recommended. Normally, this syringe has a

fixed 5cm (2 inch) stainless steel needle that is particularly suited to sample injection into the injector

described here.

3.1 Loading the syringe

The syringe loading and injection method described below has proven to give excellent reproducibility

and has the following advantages: It permits the operator to verify the precise volume of the injected

sample; it separates solvent and sample with a pocket of air; it ensures a dry needle during insertion

into and removal from the hot injector.

1) Flush the syringe thoroughly with cleaning sample solvent.

CAUTION

Never handle any injector parts that come in contact with the

carrier gas with your fingers. Always use clean metal tools

and /or figure. Never place injector parts on painted or

WARNING

BE CAREFUL FOR BURNING YOUR HANDS.

The injector nut and automatic start switch assembly may

be very hot during instrument operation and should not be

touched with upprotected hands. Don’t touch it directly

69

2) Expel the solvent from the syringe, and then carefully retract the plunger (in air) to the 1.0μl

mark. A little less than 1μl of the solvent will be present (needle holdup).

3) Transfer the syringe to the sample container and slowly draw several microliters of sample into

the syringe barrel. Remove the syringe needle from the sample container and expel sample until the

plunger is at the 2μl mark (for a 11μl injection).

4) Retract the syringe plunger, pulling the needle load entirely into the barrel. Two liquid plugs

will be seen---sample, and solvent without sample. Pay attention to the real volume of the sample.

5) Insert the needle to its full length; inject the sample and quickly remove the syringe.

3.2 Making an Injection

The other important aspect of sampling technique is the speed of injection, which cou1d affect solvent

peak tailing and thus the resolution between solvent and solute peaks with low K’. This may be

summarized as follows:

Use a fast injection speed (<<1 sec) for samp1e size less than 0.5 or 1 μl.

Use a slow injection speed ( ≤ 2 μl/sec) for sample size larger than l μl.

If a cold-trapping technique is not applied, slow injection speed is normally recommended when a

large sample volume is used in conjunction with a high volatility solvent at a high injector

temperature.

Tab1e 1 shows the recommended injection speeds for some typical solvents at two injector

temperatures

TABLE 1

RECOMMENDED INJECTION SPEEDS FOR SPECIFIC SOLVENTS

3.3 Installation of column

If the inlet end of the column is fully packed, enough packing should be removed to prevent any

needle penetration into the packing. Such repeated penetration can damage the needle, and pulverize

packing, creating an accumulation of fine particles that result in excessive column head pressure.

70

Remove packing as follows:

1) For 5Cm (2inch) needles: Remove glass wool plug. Remove packing to a depth of not less than

4cm (1.5inch), replace a glass wool plug.

2) For 7Cm (2.75inch) needles: Use the same procedures as above, except remove not less than

6cm (2.3inch) of packing.

3) In general practices, using the above guidelines, remove packing as dictated by the length of

the needle being used.

Fig 1-1 Auto-start switch

4 ONCOLUMN INJECTOR OF PACKED COLUMN

4.1 General

The on-column injector is designed for sample injection ontoФ3, Ф6 OD packed column. The inter

structure for these two injectors are shown in Fig 1-2. The notable difference between the current

injector and earlier model is the location of column sealing ferrule. This design provides for the

column seal ferrule at the upper part of the injector rather than the lower outlet end to obtain minimum

injector dead volume band spreading effect.

CROSS-SECTIONAL VIEWS OF 1040 HEATED ON-COLUMN INJECTOR

WITH 1/8” AND 1/4” OD AND MEGABORE COLUMNS

71

The 1045 injector is designed for sample Injection onto 1/8" or 1/4” OD packed columns (glass or

metal) and Megabore columns. Internal characteristics of the injector bodies are shown.

The notable difference between the 1045 injector and earlier models is the location of the column

sealing ferrule. This design provides for column sealing at the upper end of the injector rather than the

lower outlet end to obtain minimum injector dead volume band spreading effect.

When selecting correct inserts. Note: Component parts for l/4" OD columns and the Megabore

insert are the same. An insert and smaller ID ferrules are required for 1/8” column installation.

CROSS-SECTIONAL VIEW OF 1045 HEATED ON-COLUMN INJECTOR

WITH 1/8” AND 1/4” 0D AND MEGABORE COLUMNS

72

Refer to Fig. 1-2 when selecting the correct inserts, while installing Ф3、Ф6 column, the internal

diameter of the inserts and pressed ring are smaller.

4.2 Disassembling the detector

Use these steps to remove the detector from the heater block (case):

1) Disconnect the column from the injector and detector.

2) Refer to Fig.1-1, remove the injector nut. This frees the automatic start switch assembly.

WARNING

HAZARDOUS VOLTAGES PRESENT!!!

Cut off the power supply. Cool the detector down before the

73

3) Take off the automatic start switch assembly and lay aside.

NOTE: It is not necessary to disconnect the electrical leads.

4) Remove the two retaining screws on the case cover of the injector and take it out. Do not

remove, deform or tear the insulating material lining the inside of the cover of the injector. Keep it

well for reassembly.

5) Refer to enlarged view of A section in Fig 1-3. Loosen the nuts of the two main clamping

screws on the clamping plate.

6) Disconnect the carrier gas line at the tubing union, making sure the valve of gas cylinder must

be shut off.

7) Take out the injector body. If the injector body cannot be still disconnected after loosening the

clamping screws, again loosen the screws for installing cradle located at one side of the injector case

body. Refer to the enlarged view of A section in Fig. 1-3.

4.3 Disconnecting heater block thermostated container of the injector

Removal of heater block is necessary only when failure of the probe /or cartridge heater is diagnosed

and requires replacement. Its procedures are as follows:

1) Complete the steps given in 1.4.2 above.

2) Disconnect the heater/probe harness from the temperature controller PCB at J72. See Fig.1-3.

3) Remove the 4 mounting bracket screws and lift out the heater block (oven) assembly.

4) Disconnect the autostart leads from the heater/probe assembly.

5) The cartridge heater and probe are located in wells accessible from the underside of the heater

block. Remove the cartridge heater and probe and replace a new heater/probe harness assembly. See

figure1-3 for harness routing and connection to the temperature controller PCB.

Reassembly and install the detector by reversing the above steps.

74

5 COLUMN INSTALLATION FOR ONCOLUMN INJECTION

Two installation procedures are described; one for the conditioning phase of glass columns, and one

for the operating phase. The installation steps differ, since the column exit must not be connected to

the detector during the conditioning phase. For columns designed for on-column operation, the longer

leg is the inlet, or injector end of the column.

5.1 1040 Injector: Glass Column Installation for the Conditioning Phase

1) Before inserting the column into the injector, install the nut and ferrule on the longer leg of the

column, as shown.

75

2) Insert the column into both injector and detector fittings until the injector end butts against the

internal shoulder in the injector body. Thread up the injector bottom nut just tight enough to hold the

ferrule in place.

Fig. 1-4 Graphite/Vcesple ferrule before conditioning phase

Fig. 1-5 Column and ferrule positions before conditioning phase

3) Retract the column from the injector 5-7cm or enough to drop the detector end out of the

detector fittings. See figure 1-5. Tighten the nut just enough to seal the column and secure it in place.

Proceed with the conditioning phase.

NOTE

Since upper ferrule has no internal support when column is retracted, excessive pressure on

lower nut may distort or crush it. Tighten lower nut only enough to seal the column. If upper

ferrule remains lodged in the injector body, extract it with supplied tool. Replace extracted

ferrule with new one.

76

5.2 Column installation for routine operation

For packed column, insert the column into the injector until it butts against the internal shoulder. The

column installation should note the following points:

1) Disconnect the column after completing the conditioning phase.

2) Detach the two graphite ferrule and inserts, replace them.

3) Insert the column into the fitting of the injector and detector, inserting it as depth as possible.

Thread up the lower injector nut and detector, run up the bottom injector nut by hand to avoid cross

threading.

4) Use a small open end wrench and tighten nuts cautiously and only enough to obtain a good

leak-free seal without the leakage. If checking the leakage, after connecting the gas before powering

up, drop several drops of fine isopropyl alcohol on fitting of the injector and the detector. For keeping

the system cleaning without being polluted, don’t use the detergent or soup water to check the leakage.

6 FLASH VAPORIZATION SAMPLE INJECTOR

Injector bodies designed for flash vaporization of the sample differ in their internal configuration from

the on-column injector bodies as shown in Figure. 1-6.

All instructions regarding installation of the injector heater block, replacing defective heater/probe

assembly, and auto-start assembly are the same for the flash vaporization injector as those given for

the on-column injector, with the exception of column installation.

IN contrast to the on-column installation where the longer column leg is the inlet or the injector end,

for the flash vaporization, just the opposite is the case, i.e., the shorter leg is the column inlet, or

injector end.

NOTE

If upper ferrule remains lodged in the injector body, extract it

with supplied tool Replace extracted ferrule with new one

NOTE

Before heating any packed column, purge all air from the

system by flowing inert carrier gas through the column for

NOTE

The inlet end of the column can be inserted only a few

millimeters into the flash vaporization injector body. The

column seal is therefore made at the lower end of the

77

6.1 Column installation: Conditioning phase---Flash vaporization injector

In order to install the column disconnected from the detector, it will be necessary to reverse the

column, i.e., insert the longer leg (detector end) of the column into the injector, leaving the other end

free.

6.2 Column installation: Routine operation

Install the injector and detector nuts to the inlet and outlet legs of the column. Install the ferrules. Use

graphite ferrules for glass columns and VespelR, or graphite-filled vespel ferrules for metal columns.

Insert the column into the injector and detector fittings as far as internal restrictions will permit.

Tighten nuts only enough to eliminate any leaks.

Fig. 1-6 Section view of flash vaporization injector

7 SETTING THE INJECTOR TEMPERATURE CONTROL SWITCH

Injector temperature control switches are located on the temperature control PC board (S2). Use this

switch to select temperature control and displays for either the temperature programmable on-column

capillary injector (OCI) or a standard injector (STD). The STD position is used for the following

injectors: Split/spitless capillary injector; Megabore heated on –column injector; packed column

on-column injector; and packed column flash vaporization injector.

Operating procedures of the switch are as follows:

1) Turn off the instrument. Remove the instrument top covers and high voltage cover.

2) Locate the injector temperature control switch on the temperature control PC board (S2), move to

the appropriate position, OCO or STD, for the installed injector.

3) When reinstalling the high voltage cover, make sure tab on the cover is fully depressing interlock

switch (S1) on the power supply PCB. Replace the instrument top covers.

WARNING

Dangerous voltages are present under the high voltage cover.

Disconnect the instrument from AC power before accessing

switches located beneath the high voltage cover

78

Fig.1-7 Injector temperature control switch (S2) on temperature control PCB

8 SUMMARY FOR INSTALLATION AND APPLICATIONS

1) Turn off the instrument before the following operation to make all heated parts cooled down to

the room temperature.

2) Change setpta regularly. Check syringe needles for burred tips or other damage that can result

in reduced septum life.

3) Start all threaded connections by hand.-threading can make sealing impossible and result in

costly repairs.

4) Leak check with the instrument cold, using a few drops of cleaning Isopropyl alcohol (IPA) at

the fittings as a leak detecting agent.

5) Check and calibrate fuel and carrier gas flow rates.

6) Be sure the column oven fan is off while working with columns in the column oven.

7) Injector temperature control switch (S2) on temperature control PC board should be in

appropriated position, OCI or STD, see Fig. 1.7).

8) For detailed information on capillary column installation and operation refer to the following

publications: Temperature programmable on-column

Capillary injector P/N03-913921-00

Spilt/splitless capillary injector P/N03-913922-00

79

1075 Split/Splitless Capillary Injector

1 Introduction/Description

1.1 Use of this manual

Split/splitless capillary injector system is designed for chromatograph 3000 series of middle thick or

fine diameter quartz capillary columns. There are two modes (split and splitless) and four different

glass accessories on the injection system, such as: frit type (split mode), baffle type (split mode), blank

type (split mode) and open mode (splitless mode). All injector contacted with the sample are glass or

glass-lined.

1.2 Description

Split/splitless capillary injector is a multiple purpose injector. The application depends on the glass

inserts type used. Its advantages are: there is no need using polymer septum to clean the sealed septum,

less inner parts and high reliable sealing part inside.

Due to without using the polymer septum, the possibility of sample absorption is decreased more and

the injector is able to work on high limitation temperature of 400℃. It is very helpful for quick baking

out the injector. The septum holding cap provides a cleaning function. In-out air flow and carrier gas

are separately cleaned by a graphite ferrule so as to secure analytical precision, linearity and

reproducibility.

A different glass insert will be required for each mode, therefore, it is very important for convenient

and promptly disassembling and replacing the inserts during the operation. A screwdriver is only

required for replacing the glass inserts and septum.

Injector/buffer system

The injector/buffer assembly shown in Figure 1-1 has two stainless steel bodies. The glass insert is

mounted on the injector assembly, while a split ratio valve is mounted on the buffer part. After the

sample gasification, the buffer assembly is used as an air flow regulator to eliminate the change of the

flow rate caused by different viscosity between the carrier gas and the sample vaporization and

pressure twinkling increment in the injector.

Reliable septum purge is provided by a fixed air-lock, which reversely blow septum overspill and

vaporization in the injector. This way, the septum absorption is eliminated and to avoid the septum

overspill flowing into the column.

As shown in figure 1-2, the split/splitless capillary injector is able to provide four different glass

inserts. All the glass inserts has a short capillary on its top to reduce reversed spraying of the sample

vaporization. The open inserts are used for splitless injector. The narrow tune neck of the insert allows

close to contact between the sample vaporization and the column inlet, thus ensuring a highly efficient

sample re-concentration. The frit insert has a glass sand frit to secure linear split and make sample

further mixture, meanwhile providing high heat power for sample instantaneous completing

gasification.

The blank insert can fill the glass ball with silanization or with column filling agent of fluid stationary

80

phase in order to retain non-volatile compounds or particle.

Baffle inserts has less effective surface area in order to decrease the sorption of polar component up to

the minimum. Meanwhile, the outstanding thermal conductivity can be obtained for the sample

gasification.

The valve seat and valve needle of the split ratio valve (adjustable gas-lock) are all located in the

heating zone so as to secure the heat stability. There is a solenoid valve mounting on it, turn on or off

solenoid valve to control splitting outlet. The outlet flow rate can be adjusted from 10ml/min to over

1000ml/min. The solenoid valve is controlled by the computer through an external event relay,

obtaining high reproducibility.

Insert a short fused capillary column into a splitter insert as splitting point. The splitter insert is to

weld a stainless steel tube in the drive-tube. The injector is available to install A side or B side of the

instrument, the sampler is located at the rear of splitting valve (standard) or front side (reversed

rotation).

Fig. 1-1 Injector/baffle system

82

Fig. 1-2 Capillary injector inserts

1.3 Split injection mode

The split mode is the preferred method for the quantitative analysis of main compound. It is very

convenient for auto-analysis. The solenoid valve of the splitter is open during the whole running

period of GC. The split ratio for entering into the column is calculated by the flow rate passed through

the column against total carrier gas flow (Flow rate of passed column + flow rate of passed split valve),

so this split rate shows linear in the flow range of 10-1000ml/min. Concerning with application of split

injection mode and inserts in details, please refer to chapter three mentioned for the operation. This

injection mode can be used for all of frit type (split mode), baffle type (split mode) and blank type

(split mode).

1.3.1 Split injection mode

The splitless mode is used for the analysis of trace components in the sample. Its advantages are: (1) It

is available to analyze the sample with dilution less than 105.1; (2) nearby the flow out component of

83

the solvent peak; (3) It is available for a large volume sample (up to 10μL); (4) low injecting

temperature can decrease the sample dissociation; (5) splitless mode is easy to make the automation.

In splitless mode, the solenoid valve of the splitter is off just prior to several minutes when

chromatograph starts running. In this way, it is not splitting when sample enters the column. But the

sample components is re-concentrated on the column head due to “solvent effect “ by cold catching,

the separated peak shows pointed peak during temperature raising. The solenoid valve is open to purge

the residual solvent in the injector after sample injection. Since these solvent can be diffused, the

tailed reslovent peak will be seriously caused. Application of splitless injection mode and the usage of

the glass inserts are described in details in Chapter three. Open glass insert is only insert for splitless

mode.

1.4 Use of this manual

This manual will guide you in running it by yourself, maintaining the injection system of split/splitless

capillary and troubleshooting. Please carefully read “Installation” section mentioned in Chapter two

for instrument familiarization.

Normal application method and insert usage for every operation mode recommended in operation

section of Chapter three. This section is used to select the optimal operation parameters of specialized

application.

Test sample: It is provided with the detector you selected. This sample is used to check the instrument

if it is in normal case. If the tested chromatogram is not in accord with the typical chromatogram

provided, Chapter four will help you to check the problem and solve it.

1.5 Specifications

1.5.1 Injector/buffer system

Material: stainless steel

Injection mode: Split/splitless

Injector cap: Aluminum radiating fin

Auto-injection switch:

Column fitting: graphite ferrule or VESPEL ferrule.

1.5.2 High temperature septum:

Material: silicone coated Teflon

Dimension: 45” (OD) ×12” (thick)

1.5.3 Split valve

Split ratio range: 10:1 to 1000:1

1.5.4 Test Column

Fused silica capillary: 12M×0.32mm(ID)

SE-30 stationary phase.

84

1.5.5 Glass Inserts

Frit mode: Material: borosilicate glass

Dimension: 1/4” (OD) X 0.156” (ID) X 2.8” (L)

Frit body: 50-80 mesh

Blank mode:

Material: borosilicate glass

Dimension: 1/4”(OD) X 0.156” (ID) X 2.8” (L)

Baffle mode


Dimension: 1/4”(OD) X 0.156” (ID) X 2.8” (L)

Open mode


Dimension: 1/4”(OD) X 2mm(ID) X 3” (L)

1.5.6 Injector temperature

Recommended baking temperature: 400℃

Maximum temperature: 420℃

1.5.7 Pneumatics

Pressure adjustable restrictor

85

2 Installation

2.1 General

This section details the installation and disassembly of the split/splitless capillary injector,

re-installation detector inserts and replacement of the heater probe.

2.2 Removal and replacement of Glass Inserts

It is very easy to remove and replace the glass inserts of the split/splitless capillary injector. If the

insert is required for cleaning, follow the recommended cleaning procedures in Chapter

Removal:

Note: To avoid contaminating the capillary system, always use plastic gloves or figures covers to

handle the parts inside of the injector as shown in Figure 2-1 and 2-2. Remove the injector nut and

place it on a clean, uncontaminated container.

Take out the septum with tweezers or tripper supplied in the start-up kit.

Use a clean flat blade screwdriver to unscrew the septum support. Remove it with tweezers or the

point of the tripper and place it into a clean, uncontaminated container.

Inserts of frit type, blank type and baffle type: press down the insert with a tweezers to make the

graphite ferrule on the insert releasing, after so, promptly loose it. Take out the insert with the

tweezers. Doesn’t use the tip of the tripper to insert the top end of the glass insert because it is

possible to damage it. Normally take the inserts out only with the tweezers after loosing the

ferrule. When the ferrule has been over tightened and does not released, so the current dividing

part must be removed and push upwards from the button of the insert to release it. This procedure

refers to the section 2.3.

Insert of open type: To remove the insert of open type (splitless), remove the septum support per

the method above-mentioned. Loose the graphite pressed ring with the tripper or the tweezers

from one side of top part of the open type insert to another side, and then take the insert out with

the tweezers.

Replacement:

Install a new or cleaning glass insert by following steps below.

Note: To avoid contaminating the capillary system, the gloves must be used when installing the inside

parts of the injector.

Inserts of frit type, blank type and baffle type: Ware the gloves, finger covers or using the

tweezers to press the spring downwards to put the injector. The open type (splitless) insert is little

WARNING

HOT SURFACE

Injector may be hot. Take precautions to avoid burning fingers when

removing parts from a heated injector. Always place parts in a clean

86

bit up without the spring.

Sleeve the graphite ferrule (flat face up) over the bottom of the insert approximately to one-third

of the distance from the insert top part. Place the insert and ferrule into the injector body. See

figure 2-1 and 2-2. It is important only to use the graphite ferrules supplied by the manufacture

(03-949362-00); If ferrules with slightly different dimensions may not be sealed well.

Note: The graphite ferrule should be replaced periodically, typically after three or four changes

of the glass insert.

2.3 Removal and installation of splitter inserts of fused silica capillary column

The splitter inserts of fused silica capillary column must be removed when removing the glass inserts.

The glass inserts described in the section 2.2 has not been loosen yet in a normal case. The splitter

inserts of the must be detached before detach and replace heater cartridge and probe. NOTE: The

plastic gloves and finger covers must be used so as to avoid contaminating splitter inserts of the fused

silica capillary column.

2.3.1 The splitter insert should be removed from the column oven after cooling down. Before

removing the capillary splitter insert, carefully take off the fused silica capillary column and screw nut

from the splitter insert.

2.3.2 Put the parts and the fused silica capillary splitter inserts detached into a cleaning container

without the pollution.

2.3.3If it is required to take out the glass insert, use a cleaning 1/4” tube to push upwards from the

bottom of the injector so as to make the insert loosening.

Replacement of fused silica capillary splitter inserts

2.3.4 Put on the gloves or figure covers, the guide tube of the fused silica capillary splitter insert must

face up to insert it to the bottom part of the injector.

2.3.5 Tighten 1/4” stainless steel nut with hands, again rotate 1/4 – 1/2 turn with a spinner.

NOTE: Don’t make it too tightening. Otherwise the pressed ferrule might be damaged. Refer to

requirement reference table 2-1 for tightening seal. Never use Teflon plastic trip or sealed grease to

seal it.

2.3.6 Slightly rotate the screw nut of the capillary current-splitter insert. Install the fused silica

capillary column according to the section 2.7

Table 2-1 General Tightening and Retightening for Common Ferrule

Ferrule type Recommendation Comments

New graphite ferrule

Used graphite ferrule

1/4 turn past finger

tight

1/4 turn past finger

tight

1/4- to 1/2-turn past finger tight may be

required to achieve seal.

If a different size column is used, more

tightening may be required.

87

New graphite Vespel ferrule

Used graphite Vespel ferrule

1/4- to 1/2-turn past

finger tight

1/4-turn past finger

tight

May require retightening after first or

second programmed run. Over

tightening will destroy ferrule and seal.

Re-use only on same size column.

New Vespel ferrule

Used Vespel ferrule

1/4- to 1/2-turn past

finger tight

1/4-turn past finger

tight

May require retightening after first or

second programmed run. Oven

tightening will destroy ferrule and seal.

Re-use only on same size column

New stainless steel or brass

ferrule

Used stainless steel or brass

ferrule

1-to 1/4-turn past

finger tight

1-to 1/4-turn past

finger tight

May require 1/8-turn retightening after

first or second programmed run.

May require 1/8-turn retightening after

first or second programmed run.

NOTE: Do not over tighten.

88

Fig 2-2 Split/splitless capillary injector diagram

89

Fig2-3 capillary split/splitless injector system installation schematics diagram

2.4 Replacement of heater cartridge and probe assembly

Replacement of the heater cartridge and probe assembly requires removal of shunt valve, the injector

oven cover, injector oven, and splitter baffle assembly.

(1) Switch off the instrument.

(2) Turn off stabilized valve on the gas pipe line container so as to cut off the air-flow to the capillary

injector. If the hydrogen gas is used for the installed detector, only close the hydrogen gas, it is not

necessary for the others.

(3) Directly disconnect the 1/16” carrier gas line on the two-ways tube jointer of the rear of the

WARNIIG

DANGEROUS VOLTAGES PRESENT

Dangerous voltages are present during this procedure. Turn

power off and wait for the GC to cool down to ambient

temperature before operation

90

injector.

(4) Cut off pipe line of the splitter port with shunt valve at the two way jointer of the magnetic valve.

(5) Remove the injector nut and the automatic switch assembly, and put the switch and the other

cables to one side.

(6) Remove the splitter insert of the fused silica capillary column.

Removal of the shunt valve

(7) Use a spanner on the plane part of the shunt valve, another spanner is put on the 1/4” jointer,

remove the screw cap, and remove the shunt valve from the top of buffer system.

(8) Cover the tops of the injector and the buffer with a plastic cap so as to prevent heat insolating

material of the constant temperature container to enter and pollute the injector.

(9) Remove the oven cover of the injector.

(10) Disconnect wirings of the injector heater cartridge/platinum resistance on control board of power

supply.

Removal of injector oven

(11) Remove two screws located on the injector oven and take the injector oven.

(12) Loosen the clamping nuts on the injector oven as shown in Fig. 2-2 and remove the heater

cartridge and platinum resistance components. Install the new heater cartridge and platinum resistance

assembly. Be sure that the heater cartridge and platinum resistance assembly must be mounted exactly

into their respective positions in the injector oven. The heater cartridge should eb mounted nearby the

injector, tighten the clamping nuts. Both the heater cartridge and the platinum resistance must be

tightly clamped.

Re-installing the injector oven and associated assemblies

(13) Reinstall the injector oven. The wirings of the heater cartridge and the platinum resistance are

guided to the rear part, never make the cables pressed under the fixed holder, and then tighten two

pieces of the fixed screws.

(14) Insert the wirings of the heater cartridge/platinum resistance into corresponding plug of the

temperature control board as shown in Fig.2-3.

(15) Re-cover the injector oven.

(16) Removal of the plastics cap from the buffer and the injector

(17) Re-mount switch assembly and the injector cap into the original positions.

(18) Re-mount the shunt valve into the original position according to the reversely sequences of

removing procedures.

2.5 Leak Checking

Follow the following procedures to check the injector, detector inserts and pneumatics.

(1) Take off the detector barrel and flame nozzle (or other corresponding parts of the detector) to

91

expose the top of detector base. Screw sealing plug (03-999434-00 in the start kit) to the detector base.

(2) Use a non-hole vespel ferrule (28-694503-00) to block the button of the splitter inserts to be sure

the reliable sealing.

(3) Block the cleaning outlet of the septum with 1/8 plug screw nut.

(4) Adjust stabilized valve of the capillary to 50psig and turn off.

(5) If the presser gauge shows the pressure drops more than 1psig/hour, that shows the gas leakage

exists in the injector.

(6) Leak checking of the detector: firstly install the quartz capillary column per paragraph 2-6. Note:

The detector base must be still blocked.

(7) Cut off air, hydrogen and detector make up gas valve of all gas lines passed through detector. If

the TSD detector is mounted, cut off the hydrogen regulator valve.

(8) Adjust the regulator valve to 50psig and open it for several minutes to make the column flow

supplying the pressure to detector base, then turn off the regulator valve.

(9) If the pressure drops more than 1psig within one hour that shows there do leakages exist. The leak

must be eliminated as soon as possible. Firstly check column jointer and sealed clogging, but never

use soap liquid to check it.

(10) After leak checking, disassemble the septum cleaning and detector plugs, re-install the detector

system.

2.6 Connection of capillary

The fused silica capillary is a straight one, It is not necessary to make its straight before installation.

The thin polymeric coating on the quartz capillary columns prevents a certain protection against the

breakage; however, the quartz columns are somewhat fragile and must be handled with care. Note: Do

not remove the polymeric coating outside of the quartz columns.

2.6.1 Preparation of column ends

To ensure a leak-free connection of capillary columns, the ends of the column must be cut squarely

and as smooth as possible. To achieve this, a proper scoring tool is required. A fine cut tool and die

maker or jewelers file may also be used. Note: a coarser cut will give rough edges, so it should not be

used any more.

Two jointers of the column to the injector and the column to the detector must have the same screw

cap and compression ferrule. But the compression ferrule can be graphite, Vepel or graphite Vespel.

Great attention must be paid to avoid the ferrule material polluting the column.

(1). Firstly sleeve the screw cap before cutting off the end of the column, and then sleeve the

compression ferrule reversely to the column end, this step is to avoid the ferrule material polluting the

column.

(2). Tightening hold up the column with hands and cut off the sealed end. Slightly scratch the column

with the cutting tool as shown in Fig. 2-4.

92

Fig. 2-4 Cutting method of column opening

(3) Hold up the column with hands, slightly bend the column to beak it down at the scratching place

per Fig. 2-4. Check its cutting quality with a magnifying glass as shown in Fig.2-5

93

Fig.2-5 Correct and incorrect column cuts

(5). If small quartz pieces or the external coating remains on the column end, the cutting must be made

again.

2.6.2 Installation of the column

During the operation, the quartz capillary column hangs on the holder in the column oven.

Install the column after preparing the column end or after the connections of the injector and detector

inserts. It is selected by you. If the later method is selected, please refer to the paragraph 2.6.2 and

2.6.4.

The column holder should be installed at the right or the left side in the column oven. Firstly hangs the

column on the gate arm, and then turn the gate arm to the required position for the connection of the

injector and the column jointer.

NOTE: When the quartz column is connected to the injector A, the gate arm should be mounted at the

rear of the holder. If it is connected with the injector B, the gate arm should mount at the front of the

holder.

Note

In order to prevent the quartz column to drop off,

please wind both column head through the column

end around the column for several turns.

94

Fig.2-6 Position of nut and ferrule on fused silica column

2.6.3 Connection of column to injector

Put the column on the base plate of the column oven, and then follow the following procedures to

connect the column to the jointer.

(1). the capillary column nut and the reversed ferrule should be already on the column as the

paragraph 2.6.1. Note: The procedure detailed in paragraph 2.6.1 should be followed to prevent the

column contamination. The position of the screw nut and ferrule are shown in figure 2-6.

(2). Uncoil about 20cm of the column end of the detector. Move the distance between the screw nut

and the ferrule to the column end of the detector about 5cm. accurately measure 5.7cm from the

column end and mark this distance with a soft pencil. Do not allow the mark materials to contaminate

the compression ferrule.

(3). Open the closed valve of the capillary, adjust the stabilized valve of the capillary to 5-10psig. Gas

sound can be heard when the carrier gas flows into the column oven. Insert Partial column into the

lower end of the injector. Tighten the screw nut of the injector insert upwards with hands.

(4). Slowly push the column up into the injector to 5.7cm mark over the column, it is aligned until

the position of the bottom edge of the column nut is as the same with the mark 5.7cm. .

The column must be inserted into the enough depth of 5.7cm; otherwise, it cannot work in normal

case.

(5) Hold up the column as with carefully screw the screw nut of the insert. Be sure the seal is good

enough and the column is fixed firmly. Refer to the table 2-1 for the tightened extent of the

compression ferrule.

(6) If the column has not been installed on the holder, please make it according to the paragraph

95

2.6.4 Column connection to detector fittings

(1) The capillary column nut and the reversed ferrule should already be on the column as the

procedure of paragraph 2.6.1.Note: The procedure detailed in paragraph 2.6.1 should be followed to

prevent column contamination. The position of the nut and ferrule are shown in figure 2-7.

(2). Uncoil about 20cm of the detector end of the column.

(3). Move the nut and ferrule to within 10cm of the detector end of the column. Accurately measure

11.5cm from the end of the column and mark this distance with a felt pen or typewriter correction

fluid. Do not allow the nut and ferrule to fall past this mark, as the marking medium may contaminate

the ferrule.

(4). Partially insert the column into the lower end of the detector. Thread up the capillary column nut

and ferrule finger tight.

(5). Gently push the column up into the detector until the 11.5cm mark on the column is aligned with

the bottom edge of the column nut.

The column must go I the full marked distance. If it does not, the detector will not function properly.

Ensure that the column length s within 2mm of the required distance when installed.

(6). Continue to hold column as you tighten the capillary column nut carefully and only enough to

obtain a good seal and hold column firmly in place.

Note

Before the connection of the column to the detector, calculate or measure the column

flow rate.

If the column length is known, use the following equation to calculate the column flow

rate from retention time Tm of non retention peak:

m

2

4

l

T

dFc

Fc: Mean column flow rate (ml/min).

Tm: non retention peak time.

d: column inner diameter.

L: column length.111

If the accurate column length is unknown, the column flow must be measured at the

column end. Refer the paragraph 2.7.2. Suggest at the column outlet measure the low

flow, because the detector maybe has some small leakage, and cause flow deviation.

96

2.7 Pneumatics

The pneumatics system for the split/splitless capillary injector system includes a pressure regulator, a

make-up valve (or make up valves) for supplying additional gas to the detectors, a pressure gauge

showing the inlet pressure to the splitter injector, a carrier gas shut-off valve, and a series of filters and

molecular sieve and charcoal traps to remove contaminants from the gas lines.

Fig. Fused capillary detector insert

97

2.7.1 General

Instruments are delivered with gas flows set at rates established for factory final test procedures. There

should be no need to initially adjust flow rates. If you experience problems in achieving, a

representative test chromatogram, refer to the instrument operator’s manual for flow setting

procedures, using the flow rates listed in table 2-2.

Table 2-2 Requirement of Gas and filters

Detector FID ECD FPD

Carrier gas H2, He or N2 He or N2

H2 must not be used

H2, He or N2

TSD

He or N2

(If total H2 flow of

carrier gas and

detector)

Detector gas Air and H2

N2 or He as

make up gas

N2 or Ar/CH4 as

make up gas, H2 for

flush

Air and H2

N2 or He as

make up gas

Air and H2

N2 or He as make up

gas

Air #2 / / Only FPD /

Filter

Carrier gas

filter

(68-000-00)

Line filter

(03-917134-00)

Deoxy filter

(78-00056-00)

Carrier gas filter

& Line filter for

Option

Deoxy filter

Carrier gas filter

Line filter

Deoxy filter

Carrier gas

filter

for option

Deoxy filter

Carrier gas filter

for option

Deoxy filter

2.7.2 Flow measurement and adjustment

Ensure the correct operation, column, split ratio and detector flow must be measured and fine adjusted

follow below procedures.

Calculate column source flow from known column length

Note

He or N2 are better for capillary. H2 is exposure gas, if it is selected,

take care of it.

If oxygen concentration is more than 5ppm, the deoxy filter should

98

2.8 Leak checking

A convenient and non-contaminating way to leak test fittings and connections after installation or

hardware replacement procedures is to direct a small jet of gas (butane from a disposable lighter

recommended) at the point to be tested, then use the detector, at maximum sensitivity, to detect

leakage of gas into the system. Use normal column flow, a cool oven, and an operational detector. The

least preferred method of leak checking is to place a drop of pure solvent (isopropyl alcohol

recommended) on the suspected fitting or connection and look for bubbles.

2.8.1 FID leak checking

Connect methane or natural gas to a 6”, length 1/8” metal needle valve. Adjust flow to ensure the

flame is 1.5 to 2cm, and then extinguish the flame. Note the FID is during operation. Measurement

range is 1×1011A/mv. Direct a small jet of gas at the pint to be tested for several seconds, and observe

the deviation of the recorder. If the deviation is more than 50%, there is leak. Repair it. If the natural

gas is spray on the upper reaches of the column, there will be several peaks appears on the recorder,

because column split the components of the gas. Propane or butane both can be used for leak

checking.

2.8.2 ECD or TSD leak checking

The method is same as FID leak checking (paragraph 2.8.1). SF6 or Freon is for ECD. For long

capillary column (50meters or over), a quicker leak test can be made by placing a drop of methylene

chloride, measurement range is 10, attenuation is 2x.

2.8.3 FPD leak checking

Set at sulfur mode, measurement range is 10-10A/mv, attenuation is 2, then adjust zero point and obtain

a data within recorder scale. Continue follow paragraph 2.8.1. There must be odoriferous natural gas or propane commodity containing methyl mercaptan.

CAUTION

Commercial soap type leak detection fluids should not be used at any point in

a capillary system, since, if a leak is present, the fluid will penetrate and

contaminate the system. Column performance will be degraded and a

substantial period of time may be required to achieve a clean system.

99

3 Operations

3.1 Introduction

This section contains the specific operating information and procedures required for optimum

performance of split/splitless capillary injector. All installations for both the instrument and the

split/splitless capillary injector must be completed before continuing further.

3.2 Preparation before operation

Capillary split/splitless capillary should be baked out. Before baking out, the column had installed

ready.

3.2.1 Baking out injector

Initial bake out of a factory-installed injector or test column is not necessary. If bake out becomes

necessary due to contamination from handling, etc., follow the procedures or recommendations in the

following paragraphs.

It may necessary to bake out the injector if it has become contaminated during the reassembly process,

i.e., if the internal parts were placed on dirty surfaces or touched with bare hands. Then, both the

injector and column should be conditioned.

1. Disconnect column from injector.

2. The septum purge line should be open with the restrictor in place.

3. Set splitter flow between 100 and 200ml/min.

4. Install a no-hole ferrule in the capillary column nut. Thread nut up onto splitter guide assembly and

tighten.

5. Set injector temperature to 400℃.

6. Operate as paragraph 7.2.2, and bake out the injector for not less than 3 hours.

3.2.2 Cleaning the detector

It is important to cleaning the detector base contaminations for the capillary system, this procedure

can be operated while the injector baking out:

1. Disconnect the column from detector.

2. Use a no-hole ferrule to block the detector inserts end to columns.

NOTE

To prevent contamination and overheating of the fused

silica column, the column must NOT be connected to the

injector during the injector bake-out procedure.

100

3. Set the column oven temperature at 350℃, baking out the makeup gas pipeline and inserts.

4. Ser the detector temperature to 320℃, baking out the detector not less than 3 hours.

3.2.3 Baking out the column

New Columns

To minimize chemical contamination of the detector, all new columns should be baked out not less

than 3 hours before they are connected to the detector. Refer to the supplier’s recommendations for

temperature.

Used columns

Periodically (especially during extended isothermal operation), the column should be baked out to

remove accumulated contaminants. Column conditioning is required when column efficiency begins

to fall off, i.e., loss of resolution, peak tailing, severely drifting baseline, elution of extra peaks, etc.

For fused silica column with splitless sampling, especially, it is recommended that 1 to 2 turns at the

beginning of the column (approximately 1/2 meter) be cut off prior to reconditioning, as this is the end

where the stationary phase has most likely been disturbed. Attach the column to the injector and, with

carrier gas flowing, bake out the column for a minimum of 3 hours. Refer to the supplier’s

recommendations for temperatures.

Syringe leak checking

In some instances, non-reproducible chromatographic responses can be attributed to a worn and/or

leaky syringe. The syringe must be leak tight. To check the syringe, insert the needle in an injector

operating at 20 to 30 psi with a no-hole ferrule. Place a drop of solvent at suspect leak locations and

look for bubbles while moving up and down the syringe plunger.

3.3 Injection mode

Two injection modes of capillary injectors are: split and splitless.

Figure 3-1 is the schematics overview of system. Table 3-1 lists conditions of each injection mode. In

figure 3-1, S1 is solenoid on splitter vent. Splitting process can be actuated automatically. Figure 3-2a

is the working curve of each work mode.

Recommend sample volume of two work modes:

Split mode: 0.1μL to 1.0μL.

Splitless mode: 0.5μL to 3μL.

NOTE

The test column supplied with the injector has been baked

out under test conditions but requires one short bake-out

after reinstallation to remove fingerprints, etc.

101

3.3.1 Split injection mode:

Split injection mode includes three inserts: frit, blank and baffle. Refer to paragraph 3-5 for

applications of these inserts in split mode.

Frit insert

The frit insert has a short sintered-glass frit to ensure linear splitting, to promote sample mixing, and

to provide a high heat capacity for complete and instantaneous sample vaporization. It is suitable for

samples that with no glass surface absorptions. The frit insert provides large surface areas, which is

necessary for rapid vaporization. It is most widely used in samples, which is not sensitive for

decomposition and absorption.

The glass frit can collect residues and particles, and restrict carrier gas and vaporize the sample flow,

or as the absorption body.

Blank insert

Normally, a straight glass insert is needed in split mode, which is full filled with GC column filler.

Sometimes, packed inserts are must needed during measurement.

The following content explains the packed column usage in injector.

(1). Samples contains particles

Figure 3-1 Schematic overview process of injector/buffer system

102

Table 3-1 Work modes of injector/buffer system

Split mode Splitless mode

Frit Blank Baffle Open

Split ratio 10:1 o >300:1 10:1 o >300:1 10:1 o >300:1 (a)

ID of glass inserts 4mm 4mm 4mm 2mm

None small Middle None None

(b) (b) (b) (b) (b)

Air-lock

of flow

adjustable adjustable adjustable adjustable (c)

Note:

Sample and solvent to column often more than 90%. It is controlled by R4 time relay.

It depends on column ID, temperature and carrier gas.

During sampling, the solenoid is switch off (OFF), while determination, the solenoid is switch on

(ON). Please refer to figure3-2.

(2). If the thermal stability of compounds contained in samples are not good, please try to ensure the

cooling conditions of the injector vent.

(3). The fused silica capillary column is mounted on split point, so keep injector vent at constant

temperature to extend the lifetime of column. (Especially when using Carbowax and FFAP)

(4). Samples should contain easily absorbed compounds, such as pharmaceuticals.

Gloves are must needed during operation, to avoid contaminations of inner components. Use 4mm

inserts (PN 16-000833-00) to do packed inserts. Soaked in 20% (V/V) dimethyl dichlorosolane for 15

minutes to eliminate the activity, and then flush it by toluene and methanol in sequence. The optimum

is the nonpolar packed column, such as coat 3% OV-101 on the ChromosorbW-HP80-100 mesh.

Wear plastic gloves and push a piece of glass wool from lower end of the insert as plug. Push the glass

wool to top end of the insert and fill half volume of the column filler, and then push the other piece of

glass wool to avoid the removal of the filler.

103

Fig. 3-2 Flow curve figure

Baffle insert

The baffle insert has three baffles inside, which make sample steam and carrier gas mixing and having

high heat capacity in very small surface area. This mode widely used in unstable material, high polar

compounds and other samples requiring small injection surface areas.

3.3.2 Splitless injection mode

2mm open insert is used in splitless mode, which also has features of directly injection and split mode.

The WCOT column with small ID, which can inject almost samples into column. After injection, flush

the injector body by splitter, to avoid normally solvent peak tails. Refer to paragraph 3.5 for open

insert splitless injection mode application.

The splitless mode is used in trace analysis, because it requires column oven and injector temperatures

are lower. This mode can also be used in the analysis of thermal instability compounds. During trace

analysis, replace a glass insert to eliminate the contamination on the glass insert after each injection.

The capillary part of open insert is smaller than frit insert, blank insert and baffle insert. (ID is 0.03”).

This fine capillary part packs the syringe, to avoid back flash of sample vapor during injection. Almost

NOTE

This insert cannot be used in split mode, for it

cannot split.

104

10μinjector can be used in this insert. usually 1μL needle is too coarse to be used for this insert.

When splitless injection mode is selected:

(1). The recommended sample volume is 0.5 to 3μL.

(2). Injecting speed is 1μL/sec.

(3). The syringe is stop in 3 seconds to 4 minutes.

(4). During injection, switch off the solenoid, then switch on after 40 seconds or 4 minutes.

(5). The sample dilution range can be extend to 105:1.

(6). The injector temperature cannot exceed 230℃ when the sample boiling point less than 100℃.

(7). The solvent boiling point should 25℃ less than the first peak at least.

(8). The initial column oven temperature should 15~30 ℃ less than solvent boiling point.

(9). If solute peak has been eluted before solvent peak, which will not be fully separated or

quantitative analyzed.

(10). The analyzed should not exceed the concentration of component of solvent 100pmm.

Within 30 seconds after injection, almost samples and solvent steam are in the column. Switch on

splitter outlet, and flush the sample steam residues inside of the injector. (If these residues steam

diluted by carrier gas, and will cause series peak tails and lower resolution, then the column oven can

make programmed temperature raising and constant temperature operations.)

Under the required column flow speed pressure, split ratio valve is set in the range: 50~150me/min.

Flush valid time (from injection to splitter open) is 30~40 seconds.

Injection time (the time of syringe in the injector) should be than 3 seconds and less than 15 seconds.

Operate injections following manuals. Flush valid time and injection time are depends on the column

flow speed, sample volume and sample itself. When injecting large volume of samples, the septum

flush flow can be cut off during the injection.

3.4 Running the test chromatogram

We recommended that you run a test chromatogram for each detector installed to obtain a definitive

indication of instrument performance and to gain familiarity with routine entries and with switch

locations on printed circuit boards.

Retain the initial test chromatogram as a standard of comparison for later rechecking the instrument if

change in detector sensitivity is suspected. If you observe no peaks or unusual peaks after injection,

NOTE

Prior to running chromatogram, the instrument must be

installed and all pre-operational checks made as this section of

the manual.

105

turn to the Diagnostics/Troubleshooting section for assistance.

The following procedures utilize the test column(s) and test sample(s) shipped with the instrument. If

the test column has been removed, reinstall it to run the test chromatogram.

Test samples are provided for each type of detector installed in the instrument. Additional samples can

be ordered under the following part numbers:

Non-Capillary Part Number

Test Sample

FID 82-005048-00

ECD 82-005048-02

FPD 82-005048-03

TSD 82-005048-04

TABLE 3

Parameters FID ECD FPD TSD

Front panel control and

switch

Column oven switch

TSD bead current

Heater cartridge

and fan N/A

Heater cartridge

and fan N/A

Heater cartridge

and fan N/A

Detector mode

Time constant

FID STD

N/A

N2 STD

N/A

Direct

0.2seconds

TSD

N/A

Detector output switch

(set the detector does not

work to OFF)

A or B1 A or B1 A or B1 A or B1

Inject mode Splitless

Open (ID 2mm)

Splitless

Open (ID 2mm)

Splitless

Open (ID 2mm)

Splitless

Open (ID

NOTE

Table 3 lists parameters for packed column operation. If a capillary

injector is installed, refer to the appropriate injector manual for capillary

test chromatogram procedures.

Set up the test conditions and gas flow rates per Table 3 and follow the

appropriate procedure for each detector installed. If more than one

detector is to be checked, COMPLETE ONE CHECK BEFORE

106

Insert

Septum cleaning

blocked blocked blocked 2mm) blocked

Detector measurement

range page

Detector type

Attenuation

FID

32

ECD

32

FPD

256(p)

64 (s)

TSD

128

Measurement range

(Auto) zero

10-10

Y

10

Y

10-10

Y

10-12

Y

Temperature/Flow page

Injector temperature

Ion (detector) temperature

Column flow (He carrier

gas)

Column limit

320℃

300℃

2.3ml/miu

255℃

320℃

300℃

2.3ml/miu

255℃

320℃

300℃

2.3ml/miu

255℃

320℃

300℃

2.3ml/miu

255℃

Gas flow ratio

Carrier pressure

Air1

Air2

H2

Detector make up gas

Capillary column make up

8-10psi

300±Isec/min

N/A

25±1ml/min

N/A

25±1ml/min

He or N2

8-10psi

N/A

N/A

N/A

10ml/min N2

or ArCH4

20ml/min

N2 or ArCH4

8-100psi

80±2ml/min

170±3ml/min

140±3ml/min

N/A

300ml/min

He or N2

8-psi

175±5ml/min

N/A

4.0±02cc/min

N/A

30ml/min

He or N2

Time relay page

Set first page: time=0.00

Relay

OFF=-1

Set second page:

time=0.75

Relay

ON=1

100ml/min 100ml/min 100ml/min 100ml/min

107

Zero drift

No retention elution time

Colum temperature in the

sequence

Initial temperature

Raise temperature

Stop temperature

Keep time

25sec

80℃

1min

20℃/min

200℃

1min

25sec

100℃

2min

20℃/min

400℃

2min

25sec

100℃

2min

20℃/min

200℃

3min

25sec

100℃

2min

20℃/min

200℃

3min

Noise necessary inspect

condition

Detector temperature

Column temperature

Attenuation

Measurement range

Paper speed

300℃

100℃

1

10-12

1

300℃

100℃

2

1

1

300℃

100℃

4(p)

8(s)

10-10(p.s)

1

300℃

100℃

1

10-12

1

The method setting should be same as the switch setting.

After injector and detector raise temperature, and column temperature is 50℃, set baseline

temperature.

Flow speed 25memin is for chlorite solvents, flow speed 30me.min is for Non-chlorinated solvents.

Refer to 3.4.1 for the column linearity speed setting.

3.4.1 Adjust linearity speed of carrier gas through column.

Refer to table3-2, 3-3 to fine adjust carrier gas linearity speed through column, to obtain representative

chromatogram.

(1). Install test column, inject 1uL butane, propane or methane.

(2). Inject sample and record the retention time. Use 12m test column.

If the linearity speed is 48cm/sec, the retention time should be 25 seconds.

(a). If retention time is more than 25 seconds, increase the carrier gas pressure until the sample peak

retention time is 25 seconds.

108

(b). If retention time is less than 25 seconds, decrease the carrier gas pressure until the sample peak

retention time is 25 seconds.

(3). After adjustment of linearity speed, refer to running the test chromatogram.

3.4.2 FID Test Chromatogram

1. Set up instrument test conditions and gas flow rates per Table 3-2.

Note: If the makeup gas is He not N2, the peak area will be 1/2 of the N2.

2. Ignite the FID flame.

3. FID Noise and Drift Check: Set conditions per Noise and Drift Check Conditions of Table 3-2. Let GC

equilibrate for at least 4 hours.

4. Adjust column temperature to 100℃. Stabilize GC at least 1 hour.

5. Turn autozero OFF. Set printer/plotter offset to 50%.

6. Record 30 minutes of baseline, then record the noise. Noise must be 2% (at 1 × 10-12). If the detector

passes the noise and drift tests, continue with the sensitivity response check. If these noise and drift

tests were not passed, perform an additional overnight instrument bake-out, using the conditions in

Table 3-2.

7. Condition FID splitless as table 3-2, and adjust capillary pressure to make retention time of

un-retention sample (methane or butane) is 25 seconds.

8. Stabilize the GC 30 minutes.

9. Observe GC output signal drift. If drift more than 1%, continue to stabilize the GC.

10. Set measurement range is 1010, attenuation is 32, inject 1uL FID test sample. (82-00548-00).

11. Use N2 as make up gas, and the measurement range is 10-10, attenuation is 32. C14 peak height should

40% of full scale (half peak width is 1.9 seconds). If use He as make up gas, peak height will be 2

NOTE

Bake out the system several hours or overnight before running

the test chromatogram. Conditions as following:

Disassembly column, block injector inserts outlet and detector

inserts inlet with no-hole ferrule.

Column temperature: 325℃

Splitter flow: >ml/min

Injector temperature: 350℃

Detector temperature: 325℃

Test column in the column oven should be disassembly, other

columns also need disassembly.

109

times of He.

12. The chromatogram should be same as figure 3-3. With the completion of a successful chromatogram

with the test column and test sample, the GC is ready for operation. Operate as 3.5 and 3.6.

3.4.3 ECD Test Chromatogram

1. Note: ECD is sensitivity of oxygen; leak checking is necessary procedure before ECD installation.

Pressure drop should not more than 0.5 psig after 1 hour. Leak check the connection between N2

source and flow controller (see GC operation manual).

2. Install GC as paragraph 3.2, set parameters as table 3-2, install test column and turn on makeup gas.

Adjust capillary pressure; make retention time of un-retention sample (Air) is 25 seconds.

3. Stabilize GC for hours.

4. Close auto zero. Record baseline for 30 minutes and observe the detector output signal for noise and

drift. Noise should be 80% or less. If drift more than 0.5% full scale per minutes, continue to stabilize

the GC.

5. After stabilization, set measurement range as1.

6. Check ECD noise: Follow table 3-2 to condition the system, and stabilize GC not less than 1 hour.

Record 30 minutes of baseline, then record the noise. Noise must be less than 2%FS. If the detector

passes the noise and drift tests, continue with the sensitivity response check. If these noise and drift

tests were not passed, perform an additional overnight instrument bake-out, using the conditions in

Table 3-2.

7. Set measurement range is 10, attenuation is 32, auto zero is ON.

8. Hydrogen must be turned off when test chromatogram. Inject 1 uL ECD test sample (isooctane

contained 33pg lindane and 33pg azobenzene),

9. Observe the chromatogram for peak separation, peak heights, and retention times. For C14 (tetradecane,

Bake out the system several hours or overnight before running the test

chromatogram. Conditions as following:

Disassembly column, block injector inserts outlet and detector inserts inlet with

no-hole ferrule.


Splitter flow: >30ml/min



Test column in the column oven should be disassembly, other columns also

need disassembly.

The specified range and attenuation settings for ECD have been established

empirically to provide the optimum signal to the printer/plotter. The

response checks are also dependent upon these values and will be incorrect

if other detector ranges and attenuations are used.

110

peak 1), record the peak Height (H) in % of full scale deflection. The peak height of C14 should be

20%FS. If attenuation is 32, the peak height is 40% (set half peak width is 2.4 seconds.)

10. Use test column and test sample, the obtained chromatogram should be same as the figure 3-4. If it is,

the system is ready for operation. Operate as paragraph 3.5 and 3.6.

Fig. 3-3 classic test chromatograms of splitless capillary insert (FID)

Fig. 3-4 classic test chromatograms of splitless capillary insert (ECD)

3.4.4 FPD test chromatogram

111

1. Set up the instrument test conditions per table 3-2. Note: Perform the phosphorus mode determination

first, when performing FPD operation/response checks.

2. Ignite the FPD flames.

3. Allow the GC and all heating parts condition not less than 2 hours.

Phosphorus Determination

1. The phosphorus mode filter (03-905948-01) is shipped in the detector and must be in place for this

determination. If it is has been changed follow the optical filter changing procedure in the FPD

detector section for reinstallation.

2. FID Noise and Drift Check for Phosphorus Determination: Set conditions per Noise and Drift Check

Conditions of Table 3-2. Set capillary pressure to make non-retention peak (methane -butane) elution

time is 25 seconds. Let GC equilibrate for at least 1 hour. Turn auto zero OFF and observe the detector

output signal for drift. If drift is more than 2% of full scale (of chart width) per minute, allow more

time for the detector to stabilize. Then set attenuation is 8. Adjust high voltage and make noise at 1%.

3. Reset attenuation at 256 and measurement range at 10-10. Turn on auto zero. Inject 1.0uL FPD test

sample (isooctane/uL contains tributyl, sulfur out dodecane, and methyl parathion each 20ng,

pentadecane 4000ng.) automatic turn off the auto zero after injecting.

4. Observe the chromatogram separation, peak height and retention time. There will be three peaks

appear after solvent. They are pentadecane, sulfur out dodecane and methyl parathion. Record test

peak of methyl parathion, peak height should be 50% of full scale when attenuation is 256. Noise is

2% when attenuation is 4.



Disassembly column and install the no-hole ferrule below injector insert and

detector.





Test column in the column oven should be disassembly, other columns also need

disassembly.

Note

When baking out the system, the test column and other

column should be disassembly from the column oven.

The specified range and attenuation settings for ECD have been established

empirically to provide the optimum signal to the printer/plotter. The response

checks are also dependent upon these values and will be incorrect if other detector

ranges and attenuations are used.

112

5. Use test column and test sample, the obtained chromatogram should be same as the figure 3-5a. If it is,


Sulfur Determination

1. Turn off detector in GC Configure table (turns detector high voltage off). Remove the instrument top

covers and the phosphorus-mode filter. Install the sulfur-mode filter. Replace instrument top covers

and turn detector on.

2. FPD Noise and Drift Check for Sulfur Determination: Set conditions per Noise and Drift Check of

Table 3-2. Let GC equilibrate for at least 1 hour. Turn Autozero OFF and observe detector output

signal for drift. If drift is more than 1% (of chart width) per minute, allow more time for detector to

stabilize.

Once the baseline has stabilized adjust the photomultiplier tube voltage to give a noise level of 2% at

attenuation 4.

3. Sulfur detection: attenuation is 64, measurement range is 10-10, turn on auto zero. Inject 1.0uL FPD

test sample (isooctane/uL contains tributyl, sulfur out dodecane, and methyl parathion each 20ng,

pentadecane 4000ng.) automatic turn off the auto zero when injecting.

4. Observe the chromatogram separation, peak height and retention time. There will be three peaks

appear after solvent. They are pentadecane, sulfur out dodecane and methyl parathion. Record test

peak of methyl parathion, peak height (h) should be 8% of full scale when attenuation is 64 （half

peak width is 1.4 seconds.

Record the peak Height (H) of pentadecane (peak 1). Peak height should be less than 10% of the peak

height of Sulfur out dodecane.

5. Use test column and test sample, the obtained chromatogram should be same as the figure 3-5b. If it is,


Fig. 3-5a classic test chromatograms of splitless capillary insert

113

(FPD phosphorus determination mode)

Fig. 3-5b classic test chromatograms of splitless capillary insert

(FPD Sulfur determination mode)

114

3.4.5 TSD test chromatogram

1. Set up instrument test conditions per Table 3-2. Install test column. Set hydrogen flow for the TSD as

step 2.

2.

When setting the TSD hydrogen flow, disassembly TSD cylinder from detector base, and set hydrogen

flow.

Set hydrogen source to 40 psig.

Turn off hydrogen valve. (Clockwise).

Set TSD pressure gauge to 40 psig and let air to flush the system 10minutes at least.

Adjust TSD pressure until flow determined on nozzle is 4.0±0.ml/min (about 20psig). Note: pressure

setting

3. Base flow and drift test

Set bead current to FIXED (fixed offset voltage -4V). Turn off auto zero. Heating detector and injector

while column temperature is 50℃. Adjust attenuation to infinite and zero the recorder. When

attenuation is 8 and measurement range is 10-12, adjust bead current to make base flow to 50% of full

scale. Turn off auto zero, stabilize the bead, and make bead current drift less than 1% within 20

minutes (1~2 hours.).



Disassembly column and install the no-hole ferrule on injector insert and

detector.

Column oven temperature: 325℃



Ion constant oven temperature: 325℃

Test column in the column oven should be disassembly, other columns also need

disassembly.

Note

When baking out the system, the test column and other column

should be disassembly from the column oven.

NOTE

Flow rate setting for the TSD is critical. Hydrogen flow accuracy

must be within 4.0±0.2ml/min and should be made using only the

bubble flowmeter (96-000205-00). Allow at least 60 minutes for

stabilization after flows are set.

115

Fig. 3-5b classic test chromatograms of splitless capillary insert

(TSD)

4. Stabilize the detector 30 minutes.

5. Turn off TSD output switch, back to previous position. Auto zero is off. Adjust bead current to obtain

the base flow from4% ~50%.

6. Observe detector output signal drift, if the drift ia more than 2% of full scale/minute, give more time

to stabilize the detector.

7. Heating the column to reach 100℃, stabilize the base line.

Note:

Before column heating, heat the injector and detector to operation

temperature. If the detector heat the column oven at cold status,

there is may be detector contaminations.

Note

The specified range and attenuation settings for TSD have been

established empirically to provide the optimum signal to the

printer/plotter. The response checks are also dependent upon these

values and will be incorrect if other detector ranges and

attenuations are used.

116

8. TES noise check:

Set attenuation to 1, measurement range to 10-12, turn on auto zero and waiting 1~2 minutes then turn

off the auto zero. The GC enter READY (INITIALIZATION) status, and record noise for 5~10

minutes. The noise should be less than 2% (peak to peak value). In this test the drift can be 5% within

10 minutes, so the zero point offset should be more than 5 (50 is the middle on the record paper).

If the detector passes the noise and drift tests, continue with the sensitivity check. If these noise and

drift tests were not passed, give more time for instrument bake-out.

9. Sensitivity check: turn on auto zero, set attenuation to 128, measurement range to 10-12.zero offset to 5

(if the zero offset setting has changed during noise test.) the N to C selection property will affected by

hydrogen flow speed. Inject 1.0ue TSD test sample. The auto zero will turn off automatically when

injecting.

10. Observe peak separation and peak height of chromatogram

Peak number name %

1 azobenzene 20% of full scale (set half peak width is 2.5 seconds)

2 heptadecanoic not more than 22% of azobenzene peak height

11. The obtained chromatogram should be same as the figure 3-6. If it is, the system is ready for operation.

Operate as paragraph 3.5 and 3.6.

3.5 Operation

Firstly disassemble the test columns when using the capillary injectors system. Install analysis silica

column, leak checking as chapter 2. Use paragraph 3-2 to condition the GC before operation. Table

3-3 is split/splitless capillary glass inserts application recommendation.

split/splitless capillary glass inserts application recommendation.

Capillary

operation mode

Recommend

ed inserts

Typical application and samples

split Frit Pure samples, i.e. natural material, distillation of small

component content and solvent free samples.

High concentration component.

Gas analysis, using gas sampling valve for sampling on

upstream of splitter. Also used for the analysis of pyrolysis gas.

Sample with wide boiling point range.

Thermal stability or thermal inertia of the sample

Optimum split quantitative

117

Split Blank Same as 1~4 items of A.

If it is known as residual non-volatile, heavy distillate or

particulate sample. e.g. environmental protection law water

sample.

Split Baffle Same as 1~4 items of A

Suitable for A, 5 not included samples.

Splitless 2mm ID

open

Trace analysis.

Large volume sampling (≤5uL)

Sample in large volume solvent.

Thermal instability sample or absorption samples on glass

surfaces.

Sample with no low boiling point components or lowest boiling

point is at least 25℃ higher than solvent.

Headspace sampling (injection with solvent concentration.)

3.5.1 Adjust splitter flow

Splitter flow switch is controlled with solenoid valve switch (RELAY).

Press BUILD, RELAY key to display INITAL RELAY.

Press “1” ENTER switch on the splitter.

Press “-1” ENTER switch off the splitter.

Set suitable time value can automatically switch the splitter during running.

3.5.2 Set split ratio

Set split ratio from 10 to 1000ml/min by split needle valve. The needle valve orifice located on the

outlet of the buffer system. It ensures the accurate split ratio in the sampling process,

Set or reset the split ratio please according the “split ratio” procedure in chapter 2 of this manual.

3.5.3 Prevention of capillary contamination between two determinations

The capillary column is sensitivity, so prevention contaminations caused by septum washed away or

carrier gas is important. The above mentioned pollutants accumulate in the cooling columns, and

cause base line instability, and column performance degradation. The column excessive loss will

occurs during program temperature increase.

In order to decrease the column contamination, bake out the system as following:

Switch on carrier gas

Switch off the split flow

118

Switch on septum flush gas flow

Turn on column oven heater cartridges

3.5.4 Normal operation procedure

The following are particular operation procedures of split/splitless capillary column system. The

operation procedures are different from non-capillary operation procedure. Master these operation

procedures can optimize the instrument performances.

3.5.5 Injector technique

The injector techniques of split mode and splitless mode are different from each other. Using correct

injector technique when operation.

Split mode

Early peak flow is usually very sharp; sometimes the peak width is less than 1 seconds. Try to be

quick when injecting the samples. If the injecting sample time (from the injector inserting to pulling)

beyond peak width, it will cause big peak broadening and tailing. Column efficiency will be

significantly affected. Rapid injection will make less affection to a wide elution peak.

It is different mode from the split mode, please refer to 3.3.2.

3.5.6 Septum cleaning

In the injector, flush the septum by both the backflow of steam from fixed restrictor and loss materials

of septum. It can avoid the septum absorption and block the loss materials of septum get into the

column. To further reduce the loss materials contamination, replace the septum at least once a week in

normal operation. Please refer to section 3.7.2.

The septum cleaning flow, which is determined by the restrictor, located in the ID 1/8” two-ways. It is

about 2ml/min under each column head, if other flow speed needed disassembly the two-ways with

restrictor and assembly the needle valve.

In splitless mode, for big sample volume pass through septum cleaning restrictor, there will be

significant steam loss. So stop the septum cleaning flow during injection. Easily block cleaning flow

outlet, or assembly a T-ways on solenoid up-stream exhaust pipe, then to connect the septum cleaning

flow to the T-ways. The split switch can switch on or off the cleaning flow outlet, and switch on and

off spliter outlets at the same time. Caution the column contamination when septum cleaning flow half

switch off (Refer to the paragraph 3.5.3).

3.5.7 Close to highest sensitivity operation

When during or close to highest sensitivity operation, there maybe sine wave or slow base line drift.

When in FID or FPD operation, drifts may be caused by pressure change of hydrogen source, because

the outside regulator temperature of hydrogen source changes.

Normally, separating the regulator from hydrogen resource or shielding can dissolve this problem.

When the environment is specially unstable, assembly the hydrogen regulator inside the temperature

control pneumatics oven.

The carrier gas regulator is in the constant temperature oven inside the pneumatics oven. The detector

119

sensitivity is not very high for small changes of air flow.

3.5.8 Routine maintenance procedures

For optimum performance of the split/splitless injector, the following routine maintenance should be

followed. Maintenance procedures are following the normal procedures.

3.5.9 Cleaning glass inserts

Glass inserts must be clean and free from sample residues and particles. such as a bits of septum

rubber or graphite. Removal glass inserts following chapter 2 and the warning below.

Cleaning procedures will depend upon the nature of samples injected and may range from sovent

washing to hot acid oxidation or heating. Heating to 500℃ in a glass annealing oven or flaming with

a Bunsen burner will remove organic residues. Alternatively, glass inserts can be washed in a 1:1:1

mixture of methanol, methylene chooride, and hexane in an ultrasonic cleaner for 30~60 minutes, then

dried in an oven.

Glass inserts and other splitter/injector parts should be handled with tweezers or clean cotton gloves to

avoid fingerprint contamination.

3.5.10 septum replacement

Septum replacement represents the major part of routine chromatographic maintenance. Septum

damage from the needle penetrations can be avoided by injecting into the same hole and not using

syringes with needles having burrs or bends at the tip which cut the septum.

Follow chapter 2 for replacing the septum in the injector.

3.5.11 Column conditioning

7.5.12 Maintenance schedule

For optimum performance of the split/splitless injector, the following routine maintenance schedule

should be followed.

Biweekly maintenance

In normal operations, the septum, 1/4” graphite ferrule and glass inserts should be replaced once two

weeks. Bake out the system following below procedures.

NOTE

Glass inserts are at injector temperature and are probably hot. Use

care in removing them. Do not place hot inserts on a contaminating

surface, such as paint. Cool a clean glass or metal surface.

CAUTION

Handling a septum with bare fingers may result in

column contamination. Use tweezers when installing

a new septum.

120

(1). Installing fused silica test column;

(2). Setting pre-pressure of column is 10psig;

(3). Setting instrument conditions:

Injector temperature: 380℃.

Column oven temperature: 250℃.

Detector temperature: 320℃.

(The detector with the maximum operation temperature is less than 320℃, which must be disassembly

first.)

Switch on the septum clean gas flow.

Click BUILD RELAY icons, and it is displaying INITIAL RELAY. Click “1” ENTER, and turn on

the restrictor flow.

(4). Bake out the system (overnight is recommend) until the baseline is stable.

Monthly maintenance

Except biweekly maintenance, monthly inspect and clean the pipelines of injector/buffer system and

the inserts of detector.

Maintenance once every six months

Replace filters of carrier gas and hydrogen every six months. Bake out the system 1~2 days following

the biweekly maintenance schedule.

121

4 Appendix of figures

The following figures are for operator’s reference.

03-917501-00 capillary pneumatics schematics figure (3400, ECD) FIG. 4-1

03-917501-00 capillary pneumatics schematics figure (3400, FID) FIG. 4-2

03-917501-00 capillary pneumatics schematics figure (3400, TSD) FIG. 4-3

03-917501-00 capillary pneumatics schematics figure (3400, FPD) FIG. 4-4

Note

The instrument will be updated in production process, so

not every detail is consisting with the instrument.

126

Gas Sample Valves (Single Heated, Dual heated &

Unheated)

Introduction

The following figures are provided only to give part number assistance when working with single or

dual heated gas sample valves or unheated gas sample valves on 34 Series GCs.

Figure 1 Single Heated Gas Sample Valve 03-917533-00

Figure 2 Dual Heated Gas Sample Valve 03-917534-00

Figure 3 Unheated has Sample Valve 03-917535-00

NOTES FOR FIGURE 1

127

FIGURE 1

SINGLE HEATED GAS SAMPLE VALVE

130

SECTION FIVE DETECTCRS

1Thermal Conductivity Detector

1.1 INTRODUCTION

These instructions are designed specifically for installing and operating the Thermal Conductivity

Detector. The TCD is mounted directly above the column oven. The TCD PC Board is instal1ed in

the electronics cabinet.

TCD operating parameters are controlled at the keyboard, with operator set filament protection，

temperature 1imit switch and coarse zero balance. Gas flow is set and controlled at the pneumatics

panel.

WARNING

TCD cell damage will occur if an ECD is operated on a TCD-configured GC.

1.2 INITIAL SET-UP

The TCD is set up by completing the following steps:

a. Connect gas lines to appropriate bulkhead fittings on the GC.

b. Check the gas supply pressures. Flow controllers are calibrated for He=80 psig. Recalibrate if a

different supply pressure is used. The TCD may be used with Megabore columns at high flow

rates，e.g. 20-30 ml/min. (Refer to the Pre-Installation Instructions for additional information on

gas supply requirements)

3. Setting up the TCD PC Board internal switches and controls:

Figure 1 shows the board's internal switches and controls.

a. TCD Coarse Zero Balance

The TCD Coarse Zero Balance (R6) is a potentiometer located at the top of the pc board. The

zero balance point of the TCD may shift over a wide range depending on the detector and/or

filament temperatures. The range is considerably greater than the Autozero can adjust. Thus，

when first using the TCD or when changing its operating conditions, it is necessary to bring the

balance point within the range of the Auto zero.

To adjust the TCD Coarse Zero Balance, turn on autozero. Check the baseline display in the

detector status section (DDD X BASELINE XXXXX.XX MV A/Z). Monitor baseline offset and

adjust via the TCD Coarse Zero Balance to near 0.0 mV.

It is recommended that the balance be set to at most±5 mV，depending on cell operating

conditions. At this setting，balance wil1 remain in the autozero range over a wide range of

conditions. The balance should be readjusted well before it approaches the limits of

131

Autozero(±1300 mV).

FIGURE 1

TCD PC BOARD

b. TEMP LIMIT Switch and Filament Protection (Figure 1)

Set the TEMP LIMIT switch to 390℃ or 490℃，according to the highest filament temperature

setpoint which is required. (Choose the tune of carrier gas in the GC configure table.)

With the switch in the 390°position, the peak sample filament temperature is instantaneously

limited to approximately 450℃. The 1imi t temperature is approximately 550°in the 490°position.

The 450°limit will protect filaments from serious oxidation over extended periods of exposure to air,

132

while the 550°limit may allow significant degradation after only a few minutes. The detector should

always be operated with the switch in the 390°position for maximum protection unless the ultimate

in dynamic range is required.

After a long period of use in which the filaments are slowly oxidized, their resistance will increase.

This may eventually necessitate the use of the 490° switch position, even for filament temperature

setpoints slightly below 390°. When the limit temperature is reached on a large peak，you will see

flattened peaks on the chromatogram，a resulting error message，and a printer/plotter run log entry.

Built-in software protection turns off filament current when no carrier flow has been maintained for

over three minutes, or when 1ow filament current is measured for over three minutes. Filament

protection also turns off filament current for the case where only one side of the detector cell has no

carrier flow while the other side still has carrier flow, e.g., septum or column not installed or in the

case of a gross air 1eak on one side.

If HELIUM or H is chosen as the carrier gas，filament protection is enabled，as described above.

However, if NITROGEN or ArCH4 is chosen in the GC Configure tab1e，filament protection is

disabled. Since filament protection senses the presence of air(or N2 ) in the detector cells，and since

air and N2 have approximately the same thermal conductivity, filament protection mush be disabled

when operating with N2.

CAUTION

If a temperature above 390℃ is set for the TCD filament temperature when N2/H2 carrier gas

is used and air is present, rapid oxidation of the filaments will occur, as software filament

protection is disabled with N2 carrier gas. If carrier gas has been turned off prior to TCD

operation, the gas flow system should be purged of air with carrier flow for five minutes before

operating the TCD.

1.3 OPERATION

The TCD requires only carrier gas for operation. Helium or hydrogen are the recommended carrier

gases. Nitrogen can be used as a carrier gas, but may cause some loss of sensitivity and an increase in

noise. Using nitrogen also disables the filament protection software which detects loss of carrier flow

(see para.2，TEMP LIMIT Switch and Filament Protection).

CAUTION

Hydrogen is highly flammable and, if used as a carrier gas, provision must be made to vent the

gas from the TCD to a safe place.

1.3.1 Pre-0perational Set-Up

Before carrier gas can reach the TCD, two columns must be installed in the column oven. Both

columns can be packed or a combination of open tubs and packed columns can be used. In this

manual, the analytical column is assumed to be A and the reference column is assumed to be B. Note:

Side B can be used for the analytical column and side A as the reference column by reversing

133

the TCD polarity. (Installation of columns is covered in the columns section and the specific injector

manual.)

NOTE

In order to avoid contamination of the detector, condition all packed columns before connecting

to the TCD.

TCD’s are preset at the factory for a He carrier gas flow rate of 30 ml/min through both sides of the

detector. The carrier gas flow is adjusted at the pneumatics cabinet and monitored at the too exit port

on the TCD. If the analysis requires a different carrier gas flow rate, it can be changed at the

pneumatics control panel.

Once the carrier gas is flowing through the TCD, it should be set up and operated as follows:

NOTE

If the carrier gas has been turned off prior to TCD operation, the gas flow system should be

purged of air with carrier gas flow for five minutes before operating the detector to prevent

oxidation of the filament.

a. Set TC detector temperature. Allow temperature to come within 100 of setpoint. TD should

normally be set at least 200 higher than the maximum column oven operating temperature. The NOT

REANY light will remain lit until the instrument reaches temperature. A flashing decree symbol in a

zone’s status display indicates that the zone's setpoint has not been reached. Monitor both the

setpoints and actual values via the instrument Status section.

NOTE The detector should be generally be operated at a temperature at least 20℃ above the column

temperature. If the detector is operated at a lower temperature, condensation in the detector

assembly could lead to contamination.

b. Set TCD filament temperature in the detector method section and allow system to equilibrate 10-15

minutes. To obtain operating current, monitor filament current in the detector status section. The

current wi11 initially be greater than the final operating current as the detector comes into thermal

equilibrium. For best performance of the detector, TF-TD should not normally exceed 200℃.

Generally, it is desirable to use the lowest detector current possible to obtain the sensitivity required.

Set positive polarity for channel A and negative polarity for channel B.

c. Turn on autozero and monitor baseline in the detector status section. Adjust TCD Coarse Zero

Balance，if necessary. The baseline wil1 drift until the detector reaches thermal equilibrium and that

equilibrium time will always exceed the detector oven heat-up time .When the baseline is sufficiently

stable，the detector is ready for sample detection. Autozero is automatically disabled when the GC

method is in RUN.

1.3 TCD 0perational Recommendations

134

The following operating procedures pan aid in the use of the TCD.

1.3.1 Use of 0.05mV Amplification

a. Low Currents (100-150mA)

Analyses that require high filament current with a less sensitive range can often be performed

at lower currents with a more sensitive range. For example，a filament current of 120mA and

0.05 mV range and an attenuation of X1 or a filament current of 300mA and a range of 0.5 mV

gives about the same output signal. At these lower currents, detector noise is lower，stability is

higher，and filament life wil1 be longer. Thus，low current operation is recommended.

Figure 2 shows an example of low current operation.

FIGURE 2_

TCD SENSITIVITY AND AMPLIFICATION

CONDITIONS: A. Filament current: 290mA

Filament temp.:300℃

Carrier gas : He At 1.5 minutes，range and attenuation

Sample: Air, 2ml changes from 2 0.5 mV to 128 5.0 mV.

Column: 10 ft. mol. sieve,

SA 30/60 at 50 B. Filament current: 151 mA

Injection: Gas sample Filament temp.:160℃

Valve At 1.5 minutes, range and attenuation

135

TCD oven temp.:120℃ changes from 2*0.05 mV to 128 0.5 mV

1. Ne

2. O2 C. Filament current: 299 mA

3. N2 Filament temp.:300℃

At 1.5 minutes，range and attenuation

changes from 4 0.05 mV to 128 5.0 mV.

All three chromatograms shown the high sensitivity and detectivity (18ppm of neon in air) of the TC

Detector. Chromatogram S also shows that by using the bridge output signal amplifier，the same

analysis (as in A) can be obtained at half the filament current，extending filament life. The

magnification of the neon peak in chromatogram C illustrates how high filament current (300 mA)

plus high amplification can be used to increase effective sensitivity.

1.3.2 Use of 0.05 mV Amp1ification (cont.)

b. High Currents (300 mA)

Highest possible sensitivity is achieved through the combination of high currents and a 0.05 mV

range. In this situation, noise originating in the detector is due primarily to filament vibration and

flow fluctuations. At high currents the detector is most susceptible to baseline drift caused by air

leaks into the gas 1ines, improperly conditioned columns, imbalanced reference and ana1ytical flow

rates, or impure carrier gas supply. Baseline drift resulting from any of these sources will generally

increase with increasing abso1ute filament temperature. Therefore, operation should be with no

higher current than necessary.

It is best to operate with the lowest TF and TD temperatures consistent with the analysis. Continuous

operation with TF greater than 390℃ should be avoided, if possible. Filament temperatures from

390℃ to 490℃ can be obtained (TEMP LIMIT switch to 490℃). Figure 2 shows an example of

high current operation.

c. Output Signal Fed to Computer or Integrator

In situations where the detector output signal is fed into a data system or some other computer or

integrator, It is advantageous to operate in the 0.05 mV range to achieve the highest possible signal.

For example, suppose the sample peaks of interest are 0.06 mV high. These peaks could be displayed

with approximately the same recorder height using either a range of 0.5 mV with X2 attenuation or

0.05 mV range with X16 attenuation. The latter combination provides an attenuated output signal to

the Computer about 10 times the signal magnitude of the former combination.

1.3.3 Calculation of Detector Sensitivity

Detector sensitivity can be calculated as shown below:

Example 1—Known sample weigh

S=PFC/W

S=Sensitivity in mV×ml/mg

P=Integrated peak area in mV×min

W=Weight of sample in carrier gas in mg

FC=Carrier gas flow in ml/min corrected to detector temp*

136

*FC=FD(TD/TA)(1-PW/PA)

FD=Flow rate measured at detector outlet (at ambient temp.) in ml/min

TD=Detector temperature in OK

TA=Ambient temperature in OK

PW=Partial pressure of H2O at ambient temperature in torr

PA=Ambient pressure in torr

NOTE: The (1-PW/PA) expression applies only if using a bubble flowmeter

Example 2—Known Concentration of Sample in Detector

S=E/CD

S=Sensitivity in mV×ml/mg

E=Detector signal (peak height) in mV

CD=Concentration of test substance in the measured peak volume in mg/ml

Peakvolume=Peak width at half heigh (in min)×gas flow rate at detector(in ml/min)

=w·h/2×FC

1.3.4 Calculation of Detector Detectivity

1.3.5 Polarity Reversal

If an injection is made into the reference column of the GC rather than the analytical column, peaks

will be negative. Since computer processing requ1res correct polarity, polarity reversal must be

specified in the DETECTOR method section prior to the start of the run to reverse the polarity of

the detector signal. To reverse detector signal polarity, answer NO to PRGM 1 TCD X POLARITΥ

POS? Polarity reversal can also be time-programmed in the detector method section.

1.4 TCD PNEUMATICS

All 34 Series GCs equipped with TCD’s are factory tested with the flow rate1isted below. This flow

rate should be used as a starting point when checking flow rate adjustments at the pneumatics pane1.

Carr1er Gas: Helium

In1et Pressure: 80 psig

Purity: 99.995%

Column Flow Rate: 30 ml/min

Reference Column Flow Rate: 30 ml/min

NOTE

Gas filters should be tightly capped when not in use. Prolonged exposure to room air will

137

degrade their performance.

1.4 DISASSEMBLY/INSTALEATION

IMPORTANT NOTE

The TCD assembly is a factory-repairable unit only. Any disassembly of the TCD assembly by

other than a engineer will void the warranty. However, the TCD cell assembly is easily replaced

on an assembly. See below.

1.5.1TCD Oven Assembly removal For Factory Repair

a. Turn off detector.

NOTE

If a column is connected to the TCD, turn off the detector before shutting off carrier gas or

disconnecting column. This prevent air from getting into detector while filament current is on,

preventing oxidation of detector filaments.

b. Turn off gas supply to the TCD at the pneumatics panel.

c. Disconnect the TCD Power/Signal cable frog J105 on the TC6 PCB.

WARNING

DANGEROUS VOLTAGES

Dangerous voltages are present under the high voltage cover. Turn off instrument and

disconnect from ac power before connecting or disconnecting cables.

d. Remove the high voltage cover. Disconnect the TCD heater/probe harness from J71 on the

Temperature Control PCB. Refer to Figure 1

e. Disconnect columns from detector inlets. Remove the four screws securing detector inlet plate

to column oven Wall.

f. Remove the four screws holding the TCD oven assembly to the cabinet，then，carefully

remove oven assembly from instrument.

1.5.2 Replacement TCD Oven Assembly Installation

1. Reinstall the replacement TCD oven assembly and secure with four 8-32 3/8-inch screws.

Secure the detector inlet plate to the column oven wall with four 8-32 3/8-inch screws.

2. Reconnect columns. Plug in TCD Power/Signal cable to J105 on the TCD PCB. Connect TCD

heater/probe harness to J71 on the Temperature Control PCB.

3. When reinstalling high voltage cover make sure tab on cover is fully depressing interlock switch

(S1) on Power Supply PCB.

138

1.5.3 PCB Bard Remove /Installation

CAUTION

Turn instrument power OFF when removing or install pc boards.

To remove the TCD PCB Board:

1. Turn instrument power OFF. Failure to do so may allow accidental contact with dangerous

voltages or circuits when removing or installing pc boards or damage the board or GC

2. Disconnect the TCD power/signal cable from TCD board.

3. Turn yellow connector cam clockwise 90 to release board.

4. Holding metal can, ease pc board straight up and out of the plastic guide slots in cabinet. Do not

touch edge connectors if possible. Place pcb in an antistatic bag when not in instrument.

Install pc board by inserting into card guide on the right and then lowering into the connector on the

left. Never force board into cabinet and be sure that all cables are out of the way before inserting

board. Close Connector cam. Reconnect cables to detector. Look to be sure that the connectors mate.

2 Flame Ionization Detector

2.1 INTRODUCTION

These instructions are designed specifically for installing and operating the Flame Ionization Detector.

The FID is installed on the detector oven, directly above the column oven. The FID PC Board is

installed in the electronics cabinet.

139

FID electrical operating parameters are controlled from the keyboard, whi1e gas flows are set and

controlled at the pneumatics panel. Flameout is automatically detected and the user is informed via

the display.

2.2 INITIAL SET-UP

1). Connect gas lines to appropriate bulkhead fittings on the GC.

2). Check the gas supply pressures. The instrument 1s set up for: air=60psig; N2 and He=80psig, and

N2=40psig. Reset the gas flows if different supply pressures are used. If operating with

capillary columns, make-up gas (at 80 psig) is also required. (Refer to the pre-Installation

Instructions for additional information on gas supply requirement.)

3). Setting up the FID PC Board imterma1 s"1tches and comtro1s:

The FID PC Board may be located in either the first or second s1ot (DETA or DET B) in the

e1ectron1cs cabinet. Figure 1 shows the connections and the fo11oWing interna1 switches and

controls.

a. FID, TSD, Selection

(1) Check that the FID or TSD selector switch (S2, Figure 1), located at the bottom left on

boards with dual electronics only, is in the FID position.

(2) Check that the jumper in W1 (Figure 1) is in the non-PID position otherwise，a diagnostic

error will result.

b . Time Constant Switch (see Figure 1)

Switch S1, near the center top of the board, is the time constant switch. Set this s1ide

switch to NORM for most operations. The FAST position is for capillary applications

and also results in slightly higher baseline noise. Set to FAST for operation with capillary

column peaks with peak widths at half height less than 2 seconds.

Range NORM(msec) FAST(msec)

10-12 270 50

10-11 72 50

10-10 7.2 5

10-9 0.7 0.5

10-8 0.07 0.05

c. FID Balance

The FID balance requires no initial adjustment. Refer to the Diagnostics/Troubleshooting

section for the balance setting procedure.

4) Press [SHIFT] [INSTR TEST] to run the self-diagnostics to check instrument electronics.

5) Install a chromatographic column in the GC (refer to the Column section or the specific injector

140

section). If the analytical column is NOT well-conditioned, use a no-hole ferrule in the detector

column nut while conditioning the column and leave the column end loose in the oven. If the

analytical column is well-conditioned, follow the normal procedure for column installation,

conditioned; follow the normal procedure for column installation.

2.3 OPERATION

2.3.1 Checklist for Igniting the FID Flame

a. Gas flow properly set at pneumatics panel. Optimum flow rates for the 0.020” ID flame tip are:

H2=30±1 ml/min; air=300±15 ml/min; carrier=30±1 ml/min; Make-up=20 ml/min.

b. Build the method. Leave the column and injector at the preset temperature of 50℃. Set the

detector to 200℃; Attenuation to 128; range to 12; with A,/Z ON.3600’ s only: Turn

appropriate hardware and heated zones ON in the GC Configure table.

NOTE

The detector should generally be operated at a temperature at least 50℃ above the column

temperature and not below 150℃, to prevent water condensation. If the detector is operated at

a lower temperature, condensation in the detector assembly can lead to excessive noise.

NOTE

DO NOT look directly into the detector tower when attempting to ignite flame.

c. Press and hold [IGNITE A] or press [SHIET] and hold [IGNITE B], as appropriate, for

approximately 5 seconds. Release the key to turn ignitor off. The ignitor times out after 10

seconds. A/Z baseline should be ＞5mV

d. Presence of flame can be verified by hold in a cool metal object above the detector tower.

Condensation assures that flame is lit. If a flameout is detected，the Status 1ight will blink.

Press [STATUS], then [ENTER] to display all messages.

e. If no condensation is visible and if the baseline value displayed is 1ess than .5 mV attempt to

re-ignite the flame，holding IGNITE for a slightly longer time.

f. If flame does not light on second attempt，refer to the Diagnostics/Troubleshooting section

for further assistance.

WARNING

EXPLOSIVE GAS

To avoid accumulation of hydrogen and possible fire or explosion hazard, always turn off

hydrogen flow when the column is removed or when the detector is not being used.

141

2.4 INSTALLATION/DISASSEMBLY

If it is necessary to remove the detector components for inspection cleaning，parts replacement，or

installation of another detector, disassembly/reassembly instructions are detailed below for both the

FID and the detector oven.

2.4.1 FID Disassembly

Figures 2a and 2b show the installation of the FID and its cable connections. Figures 3a and 3b are

FID pneumatic schematics. Refer to the appropriate figures for your GC. Figure 4 is an exploded

view of the FID. Refer to these figures while following the disassembly procedure below.

Instrument covers should be removed.

1. Turn detector OFF in the GC Configure table.

2. Turn off main instrument gas supplies to the detector at the pneumatics panel.

142

3. Disconnect the signal and ignitor cables from their probes per Figure 2a or 2b.

4. Remove signal and ignitor probes from detector tower. Do not rotate probes as they are

withdrawn from electrical contacts in tower.

5. Remove the two 8-32 2-3 /4-inch tower mounting screws from top of detector tower.

6. Remove the tower assembly. Separate tower assembly components by removing the collector

tube and insulator from the detector tower.

NOTE

Avoid contamination of ceramic insulator and probes. If the detector is not completely cool, use

a metal tool ( such as tweezers or a hooked wire) to remove the parts from the tower assembly.

Place parts on a clean KimwipeR, never on a counter or painted surface.

7. Remove flame-tip assembly from detector base，taking care not to break the ceramic flame

tip tube or the vespel or graphite ferrule.

8. Remove and discard the aluminum seal washer from detector base. Always use a new

aluminum seal washer each time detector is reassembled..

145

2.4.2 Detector Oven Removal and Reassembly

If it is necessary to remove or replace the probe or heater cartridge, Disassembly of the detector oven

should proceed as follows. Refer to Figure 4.

WARNING

DANGEROUS VOLTAGES

Dangerous voltages are present under the high voltage cover. Disconnect instrument from ac

power and allow it to cool before connecting or disconnecting cables.

1. Turn instrument power OFF and check that instrument is disconnected from ac line power. Refer

to Figure 2a or 2b. Remove the high voltage cover. Disconnect the heater cartridge and probe harness

from J71 or J78 along the top of the Temperature Controller (TEMP) PC Board.

2. Turn off hydrogen and air at the pneumatics panel.

3. Remove detector per paragraph 4.1.

4. Disconnect column from detector.

5. See Figure 4. Remove the two screws from the detector base.

6. Remove detector base from ionization oven.

7. Remove the two 8-32 screws from the ionization oven cover and remove detector oven and

attached cover from the instrument.

8. Invert detector oven. On each side of the cover are 2 screws and lockwashers holding the cover

to the oven. Remove the screws lockwashers，and the spacers between the cover and oven.

9. Remove detector oven from cover. Carefully withdraw heater/probe assembly from oven base.

10. Insert replacement heater and probe fully into detector oven.

11. Reassemble and make connections by reversing above procedure. When reinstalling high voltage

cover make sure tab on cover is fully depressing interlock switch (S1) on Power Supply PCB.

2.4.3 FID Reassembly

Refer to Figures 2 through 6 for FID reassembly.

1. Install the flame tip (0.020" ceramic flame tip) in the detector base. Both the FID and TSD flame

tips are identical.

a. If installing the flame tip assembly with a used vespel ferrule，tighten the assembly finger-tight

v1usan extra 1/6-turn.

146

FID Reassembly (cont.)

b. If installing the flame tip with a new Vespel ferrule, tighten about 1/3-turn past finger tight.

The Vespel ferrule supplied with the iustrument has a maximum temperature

limit of 350℃, If it is ever necessary to operate the detector above 350℃，

replacement of the Vespel ferrule may be required.

2. Install a new aluminum seal washer onto the shoulder of the detector base. NOTE: For reliable

tower seal, use a NEW aluminum washer each time the detector is installed.

3. Replace detector tower on detector base and secure it with two 8-32 2-3/4-inch tower mounting

147

screws. Tighten screws alternately 1/2-turn as tower is tightened into place.

CAUTION

Handle the ceramic insulator and probes with tweezers to avoid contamination.

4. Carefully insert ignitor probe into lower arm of detector tower. Align probe key with tower arm

slot (Figure 4). Observe the orientation of the ignitor elements by looking down through the top of

the detector tower (Figure 5).The spring clip should s1ip around flame tip and make good contact.

The ignitor coi1 must not touch flame tip assembly nor be positioned directly above it. Tighten

knurled nut to secure probe.

Make sure the notch in the detector tower arm does not cut the o-ring seal.

5. Insert insulator into detector tower (Figure 6), then insert collector tube into tower. Collector tube

must not come into contact with ignitor coil.

148

6. Insert signal probe into upper arm of detector tower. Probe clip should fit around the tapered

section on the collector tube tightly enough to exert a downward force. Secure signal probe by

tightening knurled nut. Make sure the notch in the detector tower arm does not cut the o-ring seal.

7. Connect ignitor cable to ignitor probe and signal cable to signal probe.(If cables were totally

disconnected from the instrument, reconnect ignitor cable to FID connector (J83)and signal cable to

connector J82 on the FID/ TSD PC Board per Figure 1.)

2.4.4 PC Board Removal/Installation

CAUTION

Turn instrument power OFF when removing or installing pc boards.

To remove the FID PC Board:

a. Turn instrument power OFF. Failure to do so may allow accidental contact with dangerous

voltages or circuits when removing or installing pc boards or damage the board or GC.

b. Disconnect signal and ignitor cables from detector.

c. Turn yellow connector cam clockwise 90°to release board.

d. Holding metal can，ease pc board straight up and out of the plastic guide slots in cabinet. Do

not touch edge connectors if possible. Place pcb in clean antistatic when not in instrument.

Install pc board by inserting into card guide on the right and then lowering into the connector on the


board. Close connector cam. Reconnect cables to detector. Look to be sure that the connectors mate.

2.5 MAINTENANCE

149

Maintenance of the FID includes cleaning deposits from internal parts，including the flame tip,

and ferrule replacement. These maintenance procedures should be done only if there has been a

de4radation of performance.

2.5.1 Flame Tip and Internal Parts Cleaning

If the FID exhibits signal noise or frequent spiking，contamination is a possibility and cleaning may

be indicated.

NOTE

Always handle detector components with tweezers to avoid contamination.

a. Remove the detector and internal parts as outlined in para.4.1.

b. Using emery cloth，scrape deposits，e.g.，SiO2, etc.，from bore of the col1ector tube the

insu1ator, and the metal part of the flame tip.

c. If flame tip is plugged, c1ear by inserting a wire through the flame tip orifice.

d. If available，ultrasonically clean the collector，insulator, and flame tip with distilled water.

e. Flush cleaned components with methanol or acetone and air dry.

WARNING HAZARDOUS CHEMICALS

Methanol and acetone are toxic and flammable chemicals. Exercise appropriate precautions

when they are used.

f. Wipe off detector tower with acetone.

g. Clean probe arms with methanol and dry in air or air oven (maximum drying temperature of

150℃).

h. Reinstall detector as outlined in para.4.3. Note: To prevent leaks, use a NEW aluminum seal

washer each time the detector toner is reinstalled.

2.5.2 Ferrule Replacement

If a leak develops around the base of the flame tip assembly due to a deteriorated ferrule or if the

detector is to be operated at temperatures above 350°,and results in a crack, the ferrule must be

replaced. A 1eak at the ferrule may cause not se instabi1ity and 1oss of sensitivity. Be sure to select

the proper ferrule for the application. The Vespel ferrule has a maximum temperature limit of 350

℃.

3 Electron Capture Detector

150

3.1 INTRODUCTION

WARNING

RADIATION SOURCE

The Electron Capture Detector contains a beta-emitting radioactive isotope, Ni63. Users of this

detector are required by Nuclear Regulatory Commission(NRC) regulations to read the

radiation safety procedures described in the Radiation Safety Manual, P/N 03-913999-00.

The ECD is installed on the detector oven，directly above the column oven. For instruments ordered

with ECD’s, the ECD PCB is installed in the electronics cabinet.

ECD electrical operating parameters are controlled from the keyboard，while has flows are set and

controlled at the pneumatics panel.

These instructions are intended how use with DDD Kit Part number 02-001972-00, which has a

captive detector cell. This kit is authorized for distribution to General Licenses, as defined in

paragraph 10 of the Radiation Safety Manual. This manual (03-914087-00) also applies to ECD Kit

Part Number 02-001972-01, which has a removable detector cell. A Specific license is required for

possession of the-01 kit. Refer to oara4raoh 2 of the Radiation Safety Manual for the Specific

License requirements.

Due to the NRC regulations on testing，packaging, and labeling radioactive materials，additional or

replacement ECD detector cells are available only as kits and may not be purchased as separate

component parts.

WARNING

TCD cell damage will occur if an ECD is operated on a TCD-configured GC.

3.2 INITIAL SET-UP

The ECD is set up by completing the following steps:

a. Connect gas lines to appropriate bulkhead fittings on the GC.

b. Check the gas supply pressures. The instrument is set up for: N2, He, or Ar/CH4 (90:10) =

80 psig. Reset the gas flows if different supply pressures are used. (Refer to Table 1 and the

Pre-Installation Instructions for additional information on gas supply requirements.

c. Setting up the ECD PC Board internal switches and controls:

The ECD PC Board may be 1ocated in either the first or second slot (DET A or DET B) in

the electronics cabinet. Figure 1 shows the connections as well as the folio wing switches

and controls.

d. Setting up the ECD PC Board internal snitches and controls (cont.):

a) Cell-Current Select Switch

Optimum linear and dynamic ranges of response require proper selection of the ECD cell

current for the specific carrier gas used and the level of the baseline (frequency, fo) with carrier

151

gas only. This four-position slide switch (S1) is labeled ArCH4, CAP, N2STD, and N2HIGH.

For normal operation with nitrogen carrier aas, use the NSTD setting. When a greater linear

range is desired.90% Argon/10% Methane is used as the carrier gas and the switch is set to

ArCH.4

Use the CAP setting when using capillary columns where the column bleed is low and the

baseline is below 1 mV when current is set to N2STD on range 1.

In applications where unavoidable high column bleed results in too high of a baseline level

when using nitrogen carrier gas，the N2HIGH position must be used. In general the baseline

should never exceed 25 mV when measured on Range 1. When this occurs，it indicates that the

wrong reference current for the existing chromatographic conditions (choice of column, phase,

sample matrix) has been chosen. Failure to operate below 25 mV has the effect of decreasing the

useful linear range.

b) Time Constant Switch

The time constant slide switch has two settings: NORM and FAST. Set this slide switch to

NORM for most operations. Set to FAST for operation with capillary column peaks with peak

widths at half height less than 2 seconds.

NORM FAST

Range (msec) (msec)

1 200 50

10 20 5

c) Test/Normal Snitch

The test/normal slide switch (S3) is set to NORM for normal operation of the ECD. Use the

TEST position to run a manual test on the pc board. Refer to the Diagnostics/Troubleshooting

section for a description of this ECD test.

d) ECD Balance

The ECD balance potentiometer (R19) is factory set and not normally changed.

152

3.2.1 Frequency/Output Signal

The ECD PCB provides two ranges, 1 and 10. Range 1, the sensitive, is used for frequencies from 1.6

kHz to 125 kHz, while range 10 is used for frequencies from 1.6 kHz to 500 kHz.

The relationship between pulse frequency and signal is:

153

3.2.2 Operation

When initiating operation of an ECD equipped GC press [SHIFT] [INSTR TEST] to run through the automatic tests. (If any fault messages are displayed，turn to the Diagnostics/Troubleshooting section.)

Observe the following procedures when operating with an ECD:

Column and Septa Considerations

To minimize chemical contamination of the ECD, all new columns and septa must be conditioned before being used with the ECD; otherwise column and/or septa bleed may seriously decrease the ECD cell current, causing the frequency/output signal to increase to an unacceptable level (reference para.2.1).

Column Conditioning

Remove the detector end of the column from the detector when conditioning the column, so that the ECD does not become contaminated. Condition new columns that will be used with the ECD for a minimum of 10 hours at 40℃ below the maximum temperature of the column packing liquid phase before connecting the column to the ECD.

Septa Conditioning

P1ace septum in a clean glass beaker or dish and bake out in the GC oven at 150℃ for 30 minutes before installing into the injector.

Column Oven and Detector Oven Temperature Selection

In selecting ECD oven temperatures，the folio wing must be considered:

a. The maximum permissible operating temperature of the radioactive foil is 400℃，which is not exceeded at the maximum detector oven temperature. Do not add additional insulation material，as it could raise the foil temperature，reducing its life expectancy.

b. A high ion oven temperature will reduce the chance of contaminating the foil with contaminants emerging from the column.

c. The higher the temperature of the foil, the greater the migration rate of the Ni into the backing material. This process reduces the electron flux and the life expectancy of the foil.

d. Background noise increases with detector and column oven temperature.

e. A guideline for selecting detector oven temperature is:

DETECTOR TEMP=Column Oven Tem perature+30℃ and should be≥150℃

f. Allow the detector to reach its operation temperature before increasing the column temperature，so that the detector will not become contaminated by the column bleed.

34 Series GCs equipped with packed column ECD’s are factory tested with the flow rates listed in

Table 1. These flow rates should be used as a startin4 point when making flow rate adjustments at

the pneumatics panel before detector use. The flow rate is measured at the exit tube of the ECM cell.

Refer to the Installation section for flow rate measurement using the soapbubble flowmeter.

The detector cell may have to be cleaned periodically with carrier gas or a hydrogen/carrier gas

mixture.With the H2 valve option installed, the ECD pneumatics provides for use of hydrogen in the

system. Flow rates and pressures for the thermal cleaning procedure are also listed in Table 1.

154

Refer to the installation section for recommended filters for specific asses for packed column or

capillary applications.

WARNING

RADIATION SOURCE

Users should be aware of the potential radioactive contamination which might be present on

the detector cap and exit tube( Radiation Safety Manual, para. 3.2, Leak Test Procedure) when

checking or adjusting the carrier gas flow rate after the ECD has been in service for a long

period of time. Always wash your hands after handling the top of ECD.

NOTE

Each ECD kit is equipped with a TeflonR flow tube assembly. When setting/checking the flow,

the ferruled end of this flow tube is attached to the 1/16-inch OD exit tube of the ECD cell, with

the other end attached to a bubble flowmeter. To prevent cross-contamination between

detectors, keep the flow tube assembly with the ECD kit and use only with the ECD.

TABLE 1

ECD GASES, PRESSURE, PURITY, AND FLOW RATES

GAS INLET PRESSURE

AT GAS CYLINDER PURITY

RECOMMENDED

FLOW RATE(ml/min)

Carrier: N2, He, or

Ar/CH4(90:10)

Detector Make-up

(capillary):

N2 or Ar/CH4

80psig

80psig

99.998%

99.998%

30( packed column)

≤5(capillary columns)

20 to 30

Hydrogen Cleaning Procedure

H2 Carrier Gas 40psig

80psig

99.995%

99.998%

50

20-30

If it is necessary to remove the detector components for inspection cleaning，parts replacement，or


ECD and the ionization oven.

3.3 ECD Disassembly

155

IMPORTANT NOTE

In Kit Part Number 02-001972-00, the detector cell, which contains the radioactive ionization

source, is permanently contained within the detector tower and can not be removed. Do not attempt to remove the cell from the tower. Radioactive materials regulations strictly

prohibit unlicensed disassembly. Evidence of removal will avoid the warranty and will be

reported to the radioactive-control authorities.

Figures 2a and 2b show the installation of the ECD and its cable connections. Figures 3a and 3b are

ECD pneumatic schematics. Refer to the appropriate figures for your GC. Figure 4 is an exploded

view of the ECD. Refer to these figures while following the disassembly procedure below. The

detector cover and instrument top cover should be removed.

1. Turn off ECD and detector oven if no other detector on the detector oven is in use. If other

detectors are present, leave the detector oven on, and use caution, as the ECD tower and cell wi1l

still be hot.

2. Disconnect the signal and pulser cables from J106 and J107, respectively, on the ECD PC Board.

3. Carefully remove the signal and pulser probes from the detector tower arms. The signal probe

(bottom) has a twist-lock cable connector, while the pulse probe has a threaded cable connector.

NOTE

Remove probes from the tower arms before inserting the installation tool in step 5.

4. Remove the detector tower cap and insulation. See Figure 4.

WARNING

RADIATION SOURCE

When removing a used ECD, there is the possibility of radioactive contamination on the

detector tower cap. Refer to the Radiation Safety Manual for the radiation safety procedures.

DO NOT attempt to remove the detector cell from the detector tower. (See IMPORTANT

NOTE above)

158

ECD Disassembly (cont.)

a. Insert the installation tool into the detector tower assembly, over the detector cell .Loosen hex nut

until cell turns freely.

b. Remove the two 8-32 3-inch tower mounting screws.

c. Remove the detector from the detector oven.

After the detector has been removed from the instrument, install the probes in the tower arms place

cap on tower, and place the cooled detector and installation tool in the ECD case and store in c1ean，

low humidity area. Refer to paragraphs 6 and 7 in the Radiation Safety Manual for storage and

shipping procedures.

If the ECD is to be transferred to another GC，also transfer the "CAUTION RADIOACTIVE

MATERIAL” label to the front of the other GC. However，if the detector is only being removed to

gain access to the ionization oven，and wil1 be reinstalled，place the ECD in a clean, uncontaminated

area and proceed to the next paragraph.

3.3.1 Detector Oven Removal

If it is necessary to remove or replace the probe or heater cartridge, disassembly of the detector oven

should proceed as detailed below.

WARNING

HIGH VOLTAGE PRESENT

Dangerous voltages are present under the high voltage cover. Disconnect the instrument from

ac power and allow it to cool before connecting or disconnecting cables.

1. Disconnect column from detector base. (Remove detector insert if used.) Remove the two 8-32

screws from the top of the detector base.

2. Lift detector base and remove from detector oven.

3. Refer to Figure 2a or 2b，as appropriate. Remove the high voltage cover. Disconnect the heater

cartridge and probe harness from J71 or J78 along the top of the Tem 血 nature Controller (TEMP)

PCB.

4. Remove four 8-32 screws from the detector oven cover and remove detector oven and attached

cover from the instrument.

5. Invert detector oven and remove insulation packed between the detector oven cover and the base.

Loosen heater cartridge set screw. Carefully withdraw heater/probe assembly from oven base.

6. Insert replacement cartridge heater and probe fully into detector oven base. Lightly tighten set

screw.

7. Reassemble and make connections by reversing above procedures. When reinstalling high

159

voltage cover，make sure tab cover is fully depressing interlock switch(SL)on Power Supply PCB.

3.3.2 ECD Installation

The ECD may be installed on a hot base，but the column oven must be at room temperature. Refer

to Figures 2 through 5.

Note: Because of its great sensitivity for oxygen, it is recommended that the pneumatics be

pressure leak checked prior to installation of the ECD. The pressure drop should be less than 0.5

lb/hr. Leak test with the column installed and the exit at the detector base closed with the air

measuring fitting (air flow plug)，F/N 16-000505-00. Also check the connections between the N2

160

supply and the on/off valve for leaks.

a. Turn detector oven off if no other detector on the detector over is in use.

b. Remove the detector cover and the instrument top cover.

c. Take detector assembly and remove both probes (pulse and signal) from the tower arms (see

Figure 4). If present, remove paper caution tag from probe.

CAUTION

Be sure both probes have been removed from the detector tower arms before attempting to

install the detector tower. Insertion of the installation tool with the probes installed will damage

the probe electrode contacts.

WARNING

NON-SERVICEABLE ASSEMBLY

Do not attempt to remove the cell assembly which is held captive inside the tower. See

IMPORTANT NOTE at the beginning of para.4.1.

a. Check the detector tower，base，and detector cell fittings for cleanliness. Remove insulation material

from the detector tower to detector oven contact area (1/8-inch around base mounting ring; see Figure

5) to insure maximum heat conduction. Check inside the fitting (ferrule seat) and blow out any dust

or insulation debris.

CAUTION

Poor metal-to-metal contact between tower contact area and ionization oven can cause a

temperature gradient.

b. Remove the insulated detector cap.

c. Read and then remove the paper caution tag “To Prevent Stripping…”from tower mounting screw.

Position tower assembly on the detector base and loosely install the two 8-32 3-inch tower

mounting screws.

CAUTION

Use care in installing cell assembly into base. Do not cross-thread tower mounting screws.

161

FIGURE 5 CROSS-SECTIONAL VIEW OF THE ECD

d. Insert installation tool into the detector tower assembly, over the detector cell .Engage the hex nut at

the 1ower end of the cell assembly. Tighten the cell assembly snugly into the base to provide a

leak-free seal. Do not overtighten.

e. Alternately and evenly, tighten the two 8-32 x 3-inch tower mounting screws into place.

f. Carefully install the signal and pulse probes in the tower arms (Figure 5). The signal probe (bottom)

has a twist-lock cable connector and a narrow clip to engage the collector cylinder. The pulse probe

(top) has a threaded cable connector and a wide c1ip to engage the foi1 cylinder. The probes must be

inserted into the tower arms with the keys on the probes lined up with the notches in the tower arms.

If any resistance is felt during insertion, check to be sure the probes are being installed in the correct

positions.

g. Install the insulated detector tower cap. The label shown in Figure 6 is factory installed on the

detector tower of a General License Device，while the 1abel shown in Figure 7 is factory install ed on

the detector tower of a Specific License Device.

h. Connect the pulse and signal cables to the appropriate probes of the ECD, as distinguished by the

cable connectors.

FIGURE 7

RADIOACTIVE CAUTION LABEL FACTORY INSTALLED ON DETECTOR TOWER

(Specific License Device)

Serial CAUTION RADIOACTIVE

Model MATERIAL

Date

162

i. Cable connections for ECD operation require installation of the ECD PCB and the Temperature

Controller PCB. Refer to paragraph 4.4 for connections to the pc boards if installation of cables is

required or requires checking.

j. Make gas connections at the rear of the instrument. Refer to paragraph 3 and the Installation section.

k. Replace instrument top cover and detector cover.

l. Install the "CAUTION RADIOACTIVE MATERIAL" label (P/N 31-000347-00) in a visible place on

the the front GC. This label describes the ECD radioactive isotope and its amount (Figure 8)

m. Replace the installation tool in the ECD case for possible later use when removing the ECD. Retain

the ECD case for storage or possible re-shipment to the local dealer (paragraphs 6 and 7 of the

Radiation Safety Manual).

FIGURE 8

RADIOACTIVE CAUTION LABEL

TO BE INSTALLED ON FRONT OF GC BY OPERATOR

Isotope____Ni63_________

Amount_____8mCi_______

Date___________________

CAUTION RADIOACTIVE MATERIAL

3.4 PC Board Removal/Installation

CAUTION Turn instrument power OFF. Failure to do so may cause shorting of circuits when removing or

installing pc boards

Since the ECD PC Board is a slide in module, removal is accomplished by the following:

a. Turn instrument power OFF. Failure to do so may allow accidental contact with dangerous


b. Disconnect signal and pulser probe cables from detector.

c. Turn yellow connector cam clockwise 90o to release board.

d. Holding metal can，ease pc board straight up and out of the plastic guide slots in cabinet. Do

not touch edge connectors if possib1e. P1ace pcb in a c1ean anti static bag when not in the GC.

Install pc board by inserting into card guide on the right and then lowering into the connector on

the left. Never force board into cabinet and be sure that all cables are out of the way before

inserting board. Close connector cam. Reconnect cables to detector. Look to be sure that the

connectors mate.

3.5 MAINTENANCE

Routine maintenance of the ECD consists of thermal cleaning of chemical contaminants from the

detector cell. Refer to the Radiation Safety Manual (03-913999-00) for detector repair, radioactive

decontamination, foil replacement, and 1eak-test information.

163

In many cases，contaminants deposited on the radioactive foil or cell ceramic insulators can be

removed by heating. Addition of H2 to the carrier gas provides faster and more complete cleaning.

Both procedures follow.

CAUTION

If, in addition to the ECD, there is an FID or TSD installed, the FID or TSD must be removed or

Vespel ferrule replaced with a graphite ferrule before the ionization oven temperature is raised above

350℃.

NOTE

Ionization oven temperature exceeding the maximum limit of 420℃ (radioactive-source temperature

less than 400℃) cannot be entered. In the event of a hardware failure causing the maximum limit to

be exceeded, internal protection circuitry will turn off power to the heated zones.

WARNING

RADIATION SOURCE

Do not attempt to chemically clean the source. Only the engineer is authorized to remove the source

from the cell. Submerging the cell in liquid or running a liquid through the cell will move

radioactivity, contaminate the cell’s exterior, damage the insulators, and is strictly forbidden.

3.5.1 Thermal Cleaning With Carrier Gas

For thermal cleaning using N2 or Ar/CH4, use the fol1owing procedure and refer to Table 1 for flow

rates, gas pressures, and purity.

a. With carrier gas flowing through the ECD cell, increase the DETECTOR TEMP to 400℃

CAUTION AVOID FOIL DAMAGE

Carrier gas must be flowing through the detector cell before setting the DETECTOR TEMP

above room temperature. Failure to do so may damage the radioactive foil, which is not

covered by warranty.

b. Monitor the output signal while the detector heats to its maximum temperature. The signal will

show an initial increase in magnitude, then a gradual decrease as chemical contaminants vaporize.

c. Allow DETECTOR TEMP to remain at 420℃ until the signal has reached a sabl e，

unchanging level. A stable signal is an indication that the foil has been cleaned as much as can be by

this Method.

d. Reduce DETECTOR TEMP to the desired operating temperature.

Continue to paragraph 5.2 if performance is not restored by this cleaning Method.

164

3.5.2 Thermal Cleaning With Hydrogen (Only With Hydrogen Valve Installed)

Thermal cleaning of the ECD may be indicated if a steady, progressive increase in the baseline

voltage is noticed (see detector status baseline display).This increase in voltage indicates that the

detector may be contaminated from sample or high levels of column bleed.

For thermal c1eaning using H2 as a purging agent，use the fol1owing procedure and refer to Table-1

for gas flow rates, pressures, and purities.

NOTE

Extended exposure to H2 at elevated temperatures can cause temporary loss of sensitivity in the ECD

which may take several hours to regain. It is important to follow step 7 in order to restore sensitivity

after hydrogen cleaning.

a. Supply H2 gas to the ECD via the rear panel H2 in1et. (Hydrogen valve must be installed.)

b. Set the carrier gas flow to 20 ml/min and set H2，flow to 50 ml/min. Refer to Section 7 for flow

rate adjustments.

c. Monitor the output signal and increase DETECTOR TEMP to 400℃. See CAUTIONS in

paragraphs 5 and 5.1. Note: The output signal will be high with H2 added to the carrier gas.

d. Al low the DETECTOR TEMP to remain at 400℃ for 30 minutes to 1 hour (maximum) or until

the output signal reaches a stable level.

e. Shut off the H2 flow. Disconnect the H2 supply from the rear instrument in1et, then connect a

carrier supply to the H2 inlet. Maintain 20 ml/min carrier gas flow through the column.

f. Purge the line with carrier gas for at least five minutes to remove any residual H2 gas, then close

the valve (disconnect the carrier gas supply from the H2 inlet*).

g. Let carrier gas flow through the detector overnight with the detector at normal operating

temperatures.

Refer to paragraph 4 of the Radiation Safety Manual for foil replacement information if

performance is not restored by these cleaning methods.

3.5.3 Operation of the Null Circuit

An extremely clean ECD system can be subject to the influence of a contact potential occurring

within the ECD. Your 34 Series GC has an additional potentiometer to completely null out a contact

potential.

The 34 Series ECD pc board (see Figure 8) has an additional factory reset potentiometer. When the

ECD is operating in the cappi1ary reference current position (CAP, switch S1) and the ECD is

below-2.0mV with autozero on and detector at range 1, this null circuit should be adjust to allow

the ECD to operate properly.

165

Null Circuit Setting Procedure

1. Remove instrument too covers. Set the cell current select switch (switch S1) to CAP.

2. Using a suitable screwdriver, adjust the pulling potentiometer (see Figure 9) clockwise while

monitoring the detector autozero. Turn the potentiometer until the autozero reading is between +2 to

+5mv.

*Not required when make-up valve option is installed.

3. Replace instrument covers and al1ow GC to stabi1ize for 15 minutes. If the autozero drifts

below zero millivolts，repeat the procedure.

IMPORTANT NOTE

DO NOT use the Null Circuit Setting Procedure when the ECD current select switch is in any

other position than CAP.

SET THE POTENTIOMETER COMPLETELY COUNTER CLOCKWISE (CCW) WHEN

USING ANY SETTING OTHER THAN THE CAPILLARY REFERENCE CURRENT. Fail to

do so can result in decrease linear range of the ECD. Do not use the null circuit to zero the

ECD; increasing the null setting will only serve to set the operating the point at a higher

frequency, which will decrease the linear range, and increase the noise of the detector.

4 Thermionic Specific Detector

4.1 INTRODUCTION

These instructions are designed specifically for instal1ing and operating the Thermionic Specific

Detector. The TSD is instal1ed on the detector oven. The FID/TSD PC Board is installed in the

electronics cabinet.

166

TSD electrical operating parameters are controlled from the keyboard. while gas flows are set and

controlled at the pneumatics panel.

4.2 INITIAL SET-UP

The TSD is set up by completing the following steps:

a) Connect gas lines to appropriate bulkhead fittings on the GC.

b) Check the gas supply pressures. The instrument is set for: air=60 psig; H=40 psig; N2 or He=80

psig. Reset the gas flows if different supply pressures are used. (Refer to the Pre-Installation

Instructions for additional information on gas supply requirements.)

c) Setting up the PC hoard internal snitches and controls

Refer to Figure 1 for connections as well as the following internal switches and controls.

� FID, TSD

(1) Check that the FID or TSD selector switch (S2.Figure 1), located at the bottom left on

boards with dual electronics only, is in the TSD position.

(2) Check the the jumper in W1(Figure 1)is in the non-PID position otherwise，a

diagnostic error wil1 result.

� Time Constant Switch

Switch S1，near the center top of the board, is the time constant switch. Set this slide switch to

NORM for operation with packed columns and peaks with widths at half height greater

than 2 seconds. The FAST position is for capi11ary applications and also results in slightly

higher baseline noise. Set to FAST for operation with capillary column peaks with peak widths

at half height less than 2 seconds.

NORM FAST

Range (msec) (msec)

10 270 50

10 72 50

10 7.2 5

10 0.7 0.5

10 0.07 0.05

� Bias Vo1tage Potentiometer

The bias vo1taoe potentiometer, R34, is a screwdriver-adjusted potent1ometer factory set to -4V,

which is norma11y used for nitrogen and phosphorus detection.

This potentiometer allows the bead polarization voltage to be operated at from zero to -12v. A fu11y

clockwise position on the potentiometer is the most negative setting.

At bias voltages between -2 and -12V, the bead produces negative 1on current, and at bias voltages

167

between O and -2V, positive ion Current is measured at the co11ector. This is because there is about a

2V drop across the heater coil in the bead. The max1mum response to n1trogen and phosphorus with

minimum detector background signals is obta1ned w1th negative 1on currents.

Bias voltage is disp1ayed to 0.1V resolut1on 1n the detector status displays.

� TSD Ba1ance

The TSD balance potentiometer (R17) is adjusted through the hole in the top of the metal can at the

top of the F1D/TSD PCB. See Figure 1. Adjust the ba1ance if the detector exhibits the following

symptoms:

Autozero the TSD at range 12. Turn autozero OFF. Change to ranges 10, 9, and 8. If the baseline

moves more than 3 to 5%, you may want to adjust the balance to maintain a constant base1ine

throughout the ranges.

Set the TSD balance using the fo11owing procedure:

1. Set TSD range to 10-12.Turn autozero ON.

2. Turn autozero OFF. Set TSD range to 10-8.

3. On a 1-mV chart recorder, w1th recorder attenuation set at 1, adjust the TSD ba1ance for

zero +/- 1 minor division on the chart recorder.

4.3 OPERATION AND OPERRTING RECOMMENDATIONS

TSD operation requires hydrogen, a1r, and e1ther nitrogen or helium carrier gas. The amount of

hydrogen re1ative to the other gases wi11 affect nitrogen-to-carbon and phosphorus-to-carbon

spec1ficity of the detector. The n1trogenoto- phosphorus spec1f1city a1so may vary somewhat but

the detector cannot be tuned to respond to on1y nitrogen or on1y phosphorus.

4.3.1 Bead Conditioning

The parameters in this and the following sub-paragraphs determine detector response and should

assist in achieving more accurate results with the TSD.

The TSD bead probe has been conditioned at the factory. However, your may choose to do some

additional conditioning to perfect detector performance. A new TSD bead probe typically has higher

background current，greater noise and greater sensitivity than a probe which has been in operation for

a day or two.

168

Bead Conditioning (cont.)

Each bead probe will, have a particular bead current (i.e., temperature) at which its gas-phase

chemistry will initiate. In order to operate the detector end to further condition the bead, it is

necessary to find this current for your particular probe. The following procedure is recommended:

1. Set the following conditions:

Gas flow rates: Air: 175 ml/min

Hydrogen: 4.5 +/-0.5 ml/min

Carrier Gas: 30ml/min

Make-up (capillary use only): 25 ml/min

Temperatures: Column: 175℃

Injector: 250℃

169

Detector: 250℃

3600's only: Turn appropriate hardware and heated zones ON in the GC Configure table.

Other: Attenuation: 256

Range: 10-12 A/mv

A/Z off; recorder zeroed

2. Set bead current to 3.4 A. A positive rise of the background signal should be observed.

Increase the bead current to obtain a 25+/-5% baseline offset from zero.

3. Inject 1 ul of TSD test sample (P/N 82-005048-04). Note that the RUN light should be on. A

typical test chromatogram should be obtained. (Refer to the TSD representative test chromatogram in

the Installation section).

4. Reduce the bead current by 0.1 A. Al1ow the bead temperature to stabilize, observed as a

steady baseline (about 10 minutes). Adjust the attenuation so that the baseline is below 30%. Inject

1ul of TSD test sample.

5. Continue to repeat step 4 At some bead current, the test sample will extinguish the bead

“flame,” arid the bead’s surface temperature will be too cool to reignite it. When this situation is

encountered, the recorder will respond with negative peaks，or a sudden loss of baseline.

6. Increase the bead current by 0.lA. This current setting establishes the minimum bead

temperature needed for detector operation. Over the next few days of operation，the background will

decrease noise will improve，and sensitivity will be somewhat reduced. After this conditioning period,

the background, noise，and sensitivity will stabilize at acceptable levels.

7. If the heptadecane peak is greater than 25% of the azobenzene peak, reduce the hydrogen

flow until the proper ratio is achieved. Repeat the above steps, if

necessary.

NOTE

The detector should be generally be operated at a temperature at least 20 to 50℃ above the

column temperature and not below 120℃ to prevent water condensation. If the detector is

operated at a lower temperature, condensation in the detector assembly could lead to increase

noise and poor quantitation.

4.3.2 Optimization of the TSD Using the Test Sample

The sensitivity of the TSD (nitrogen，phosphorus detector) is highly dependent on bead temperature

and the selectivity is dependent on hydrogen flow. In addition, there are s1 fight variations from bead

to bead and a bead changes slowly as it ages. Therefore, optimum operating conditions for a given

TSD cannot be specified exactly and the user should determine that the detector is performing at or

better than the specifications.

The detector responds to both nitrogen and phosphorus. It is not possible to significantly change the

170

relative response of nitrogen to phosphorus.

4.3.3 Determining Optimum Hydrogen Flow

Al though a nominal hydrogen flow of 4.5 ml/min is suggested，the nitrogen-to-carbon selectivity

versus hydrogen flow often differ s1ightly from bead to bead. Consequently，for each new bead it is

useful to chromatograph the detector test sample at several values of hydrogen flow(from 4 to 5.5

ml/min) in order to determine the best hydrogen flow for that bead.

In order to verify that the factory specifications are being met, use the packed test column that is

shipped with all instruments and the TSD test sample (P/N 82-005048-04) and run the TSD the

Instal1ation section. Also refer to Optimization of Nitrogen-to-Carbon Selectivity in the

Installation section.

4.3.4 Maintaining Optimum Conditions

If the detector is used daily，the power to the bead may be left on overnight at 2.4 to 2.6 amps. As the

bead ages，it will require a higher current to maintain a given bead sensitivity. Therefore, elevation

above the baseline should be checked every few days. Eventually sensitivity will be lost and it will be

necessary to replace the bead (P/N 03-906074-00). The hydrogen flow does not need to be changed

during the lifetime of a bead.

4.3.5 Column Considerations

To minimize contamination of the detector by column b1eed，all new columns should be conditioned

before they are connected to the detector. Condition new columns for a minimum of 24 hours at 40℃

below the maximum temperature of the column packing liquid phase.

Since the TSD detects compound containing N2 or phosphorus, column packing materials containing

these elements should be avoided. Common 1iquid phases containing N2 are OV-225，OV-275, EFAP,

XE-60, and TCEPE. If you must use such columns，it is important that they be well conditioned and

operated at as low a temperature as possible in order to minimize column b1eed. High column bleed

produces high background signals, making it difficult or impossible to set the bead current and can

result in the occurrence of negative peaks in the chromatogram.

4.3.6 solvent Considerations

When the TSD is used for trace 1evel analysis，only solvents free of nitrogen，phosphorus，sulfur，

or halogenated com pounds should be used. Depending on the volati1ity of the impurity in a solvent,

it can produce excessive solvent tailing or extraneous chromatographic peaks.

Chlorinated Solvents

Chlorinated solvents can be used with the TSD. However，these solvents generally cause an abrupt

increase in both detector background signal and sample response. These effects appear to be

associated with a temporary adsorption of chlorinated species onto the surface of the hot

alkali-ceramic bead. Repetitive injections of samples in chlorinated solvents yield constant responses.

However，once the injection of chlorinated solvents is stopped, the background and sample response

will decay back to the response levels that existed before the initial injection of the chlorinated

solvent. Therefore，when chlorinated solvents are used，calibration standards should be run

frequently.

171

Effect of Silylation Reagents

Silylation reagents affect the TSD in two ways. First，such reagents sometimes contain N2 which will

cause tailing of the solvent peaks. Second，decomposition of the reagent on the hot bead produces

SiO2 Which deposits on the bead surface causing loss of response. Generally, SiO2 deposits can be

removed by the cleaning procedures of para.6, and usually produce no permanent damage to the

bead.

Bead Power Interruption

The effects described above for chlorinated solvents and sily1ation reagents, particularly with 1arge

(≥3ul )injection volumes, can be minimized by having the bead at a to temperature when the solvent

is e1uteri from the column. The total time that the head is turned off should be less than 2 minutes in

order to minimize thermal re-equilibration times of the detector. (Any peaks eluting during this “off”

time will not be measured.) Set the TSD bead power to off (enter NO). Turn TSD bead power back

on by entering YES.

4.4 TSD PNEUMATICS

34 Series GCs equipped with packed column TSD’s are factors tested with the flow rates 1isted in

Table 1. These flow rates should hp used as a starting point when checking flow rate adjustments at

the pneumatics panel before detector use.

NOTE

Shut off the hydrogen flow when detector is not in use. Escaping hydrogen is a potential hazard.

TABLE 1

TSD GASES, PREUSSURE, PURITY, AND FLOW RATES

GAS INLET PRESSURE


RECOMMENDE

D FLOW RATE

Carrier (packed column)

He or N2 80psig 99.998% 30ml/min

Detector Make-up( capillary columns)

He or N2 80psig 99.998% 25+/-1ml/min

Detector Gases

Air

H2

60psig

40psig

CGA Grade E

99.995%

175+/-5 ml/min

4.5+1/-0.5ml/min

4.5 INSTALLATION

It may be necessary to remove the detector components for inspection，c1eaning，parts replacement，

or installation of another detector. Disassembly/reassembly instructions are detailed below for both

172

the TSD and the detector oven. Refer to paragraph 6 to determine when cleaning is indicated.

4.5.1 TSD Disassembly

The TSD is mounted on the universal detector base in the detector oven and is usually installed on the

rear detector oven.

Figures 2a and 2b show the installation of the TSD and its cable connections. Figures 3a and 3b are

TSD pneumatic schematics. Refer to the appropriate figures for your GC. Figure 4 is an exploded

view of the TSD. Refer to these figures while following the disassembly procedure below.


1. Turn off TSD.


3. Disconnect the signal and the ignitor cables from the TSD per Figure 2a or 2b，as appropriate.

4. Remove the two 8-32 x 3-inch tower mounting screws and the two 8-32 x 1/4-inch screws from

the top of the detector tower and top clamp，respectively.

NOTE

Use clean cotton gloves or tweezers when handling internal parts of TSD.

CAUTION

Avoid contamination of ceramic insulators and probes. If the detector is not completely cool,

use a metal tool ( such as tweezers or a hooked wire) to remove parts from the tower assembly.

5. Remove the upper insulator.

6. Remove the signal probe. There may be some resistance to removal .due to the O-ring seals. Do

not rotate probe as it is withdrawn from electrical contacts in tower.

7. Remove the collector and the lower insulator with tweezers.

8. Remove the bead probe. There may be some resistance to removal, due to the O-ring seals. Do

not rotate probe as it is withdrawn from electrical contacts in tower.

9. Carefully remove flame do assembly from detector base.

10. Remove aluminum seal washer from detector base.

4.5.2Detector Oven Removal

If it is necessary to remove or replace the probe or heater cartridge，disassembly of the detector oven

should proceed as detailed below; Otherwise continue to paragraph 5.3, TSD Reassembly.

WARNING

173

HIGH VOLTAGES


power and allow to cool before connecting or disconnecting cables.

1. Check that instrument power is OFF and that instrument is disconnected from ac line power.

Remove the high voltage cover. Refer to Figure 2a or 2b. Disconnect the heater cartridge and probe

harness from J71 or J78 along the top of the Temperature Controller (TAMP) PC Board.

2. Disconnect column from detector base. (Remove detector insert if used.) Remove the two 8-32

screws from the top of the detector base.

3. Disconnect both air and hydrogen from their respective concoctions at tie air and hydrogen

valves.

4. Lift detector base and remove frog ionization oven.

5. Remove four 8-32 screws from the ionization even cover and remove detector oven and attached

cover from the instrument.

6. Invert detector oven. On each side of the cover are 2 screws and lockwashers holding the cover

to the oven. Remove the screws, lockwashers, and the spacers between the rover and the oven.

7. Remove detector oven from cover. Carefully withdraw heater/probe assembly from oven base.

8. Insert replacement cartridge heater and robe fully into detector oven.

9. Reassemble and sake connections by reversing above procedure. When reinstalling high voltage

cover, make sure tab on cover is fully depressing interlock switch (S1) on Power Supply PCB.

4.5.3 TSD Reassembly

Refer to Figures 2a or 2b, 4 and 5, for reassembly orientation, and cable connections.

1. Install the flame tip in the detector base. This is a 0.020-inch ID ceramic flame tip. Both the TSD

and FID flame tips are identical. DO NOT use a 0.010-inch flame tip for the TSD.

a. If instal1ing the flame tip assembly with a used Vespel ferrule, tighten the assembly

finger-tight p1us an extra 1/6-turn.

b. If inatal1ing the flame tip assembly with a new Vespel ferrule, tighten about 1/3-turn past

finger tight.

The Vespel ferrule a supplied with the instrument his a maximum temperature limit of 350℃.

If it is ever necessary to operate the detector above 350℃, replacement of the Vespel ferrule

with a graphite ferrule may be required.

2. Install a new aluminum seal washer onto the shoulder of the detector base.

NOTE

For a reliable tower seal, use a new aluminum washer each time the detector is installed.

176

TSD Reassembly (cont.)

1. Measuring the nominal 4.5 ml/min H2 flow for the TSD may be simplified at this time by attaching

a tube to flame tip, and then connecting the tube to a soapbubb1e f1owmeter (P/N 96-000205-00

recommended). The s method e1im1nates flow measurement errors, which may be caused by leaks

due to poor seals.

2. Replace detector tower on detector base and secure with the two 8-32 screws. Tighten screws

alternately as tower is tightened into place.

3. Careful1y insert bead probe into 1ower arm of detector tower. Align probe key with tower arm

slot (Figure 4).

4. Secure bead probe by tightening knurled nut.

5. Insert lower insulator with shoulder down into detector tower, and then insert collector tube with

grid down. Make sure the punch mark on the ton edge of the collector is toward the probe arm.

6. Insert signal probe into upper arm of detector tower. Carefully align the spring clip with the

collector. Be sure the key on the probe and the tower arm are aligned. Secure signal probe by

tightening knurled nut.

7. Assembly the upper insulator and top c1 amp over the collector. The O-ring wil1 provide slight

resistance to complete insertion. Take care not to tear the O-ring or the tower wil1 not seal properly.

8. Look down the tower assembly to verify that the bead does not touch the collector. Carefully

adjust the collector as necessary.

9. Assemble the top clamp to the tower and secure with the two 8-32 screws.

10. Connect the signal cable to the signal probe (top) and the ignitor cable to the bead probe (bottom).

If cables were totally disconnected from the instrument, reconnect signal cable to J82 at the too of the

SID/TSD ac board and the bead current supply cable to J84 below the can.

178


CAUTION

Turn instrument power OFF when removing or installing pc boards.

To remove the TSD PC Board:

1. Turn instrument power OFF. Failure to do so may a11ow accidental contact with dangerous


2. Disconnect signal and ignitor cables from detector.

3. Turn yellow connector care clockwise 90o to release boar.

4. Holding metal can, ease pc board straight up and out of the plastic guide slots in cabinet. Do not

touch edge connectors if possible. Place pcb in clean antistatic bag when not in GC.

Install pc board by inserting into card guide on the right and then lowering into the connector on

the left. Never force board into cabinet and be sure that all cables are out of the way before

inserting board. Close connector cam. Reconnect cables to Detector. Look to be sure that the

connectors mate.

4.6 CLEANING/MAINTENANCE

179

When the TSD exhibits low sensitivity or high background noise, cleaning is indicated. Visual

inspection may also indicate need for c1eaning. The flame head，collector，or flame tip are al1 harts

that are deposit prone, depending on the type of samples being used. Clean these parts as indicated in

the following paragraphs.

NOTE

Always handle detector components with tweezers to avoid contamination.

4.6.1 Bead Cleaning

Non-volatile deposits can be removed from the bead by gently scraping tube bead surface with a

sharp tool or abrasive paper. The bead should be，unsorted while being cleaned to present bending the

lead and cracking the ceramic coating on the leads.

4.6.2 Flame Tip and Internal Parts Cleaning

1. Remove the detector and internal parts as outlined in para.5.1. Handle internal parts with

tweezers and place on a clean, uncontaminated surface.

2. Clean deposits from the surface of the collector with water or abrasive paper.

3. Remove deposits which form on top of the flame tip by scraping. If flame tip is plugged, clear by

inserting wire (approximately 0.012 inch diameter) into flame tip orifice.

4. Flush cleaned components with methanol and air dry.

WARNING

HAZARDOUS CHEMICALS

Methanol and acetone are toxic and flammable chemicals. Exercise appropriate precautions when

they are used.

4.6.3 Ferrule Replacement

If 1eak develops around the base of the flame tip assembly due to a deteriorated ferrule or if the

detector is to be operated at temperatures above 350oC，and results in a crack，the ferrule must be

replaced. A 1eak at the ferrule may cause noise instabi1ity and 1oss of sensitivity. Be sure to select

the proper ferrule for the application. The Vespel ferrule has a maximum temperature 1imit of 350℃.

To replace the ferrule，disassemble the TSD per paragraph 5.1 and reassemble per paragraph 5.3.

5 Flame Photometric detector

180

5.1 INTRODUCTION

The FPD selectively detects phosphorus or sulfur-containing compounds by burning the effluent of a

GC column in an air-hydrogen flame then measuring a selected spectral portion of the light emission

from the flame. The FPD utilizes two sir-hydrogen flames to separate the region of sample

decomposition from the region of light emission to be measured. Phosphorus compounds emit a

green light and sulfur compounds emit a blue light. In the case of phosphorus, the greed emission is

from excited HP0 molecules and the light intensity is linearly related to the flow rare of phosphorus

atoms into the flame. In the case of sulfur, the blue emission is from excited S2molecules and the

light intensity varies as the square of the sulfur atom flow into the flame. An optical filter is used to

select the emission spectrum to be measured. See para.6.3 for filter changing. The phosphorus filter is

installed at the factory.

These instructions are designed specifically for installing and operating the Flame Photometric

Detector. The FPD is installed in the rear position or the rear oven on the GC. The FPD PC Board is

installed in the electronics cabinet.

FPD electrical operating parameters are controlled from the keyboard. Gas flows are set and

controlled at the pneumatics panel. Flameout is automatically detected and the user is informed via

the display.

5.2 INITIAL SET-UP

Connect gas line to appropriate bulkhead fitting on the GC.

Check the gas supply pressures. The instrument is set up for: N2 or He =80psig; H2=40psig;

air=60psig. Reset the gas flow if different supply pressures are used. (Refer to the Pre-Installation

Instructions for additional gas requirements.)

Setting up the FPD PC Board internal switches and controls:

Figure 1 shows the cable connections as well as following internal switches and controls.

a. Internal Time Constant Switch (Figure 1)

Switch S1, near the center top of the board, is the internal time constant switch. Set this slide switch

to NORM for most operations. The FAST position is for capillary applications and also results in

slightly higher baseline noise. Set to FAST for operation with capillary column peaks with peak

widths at half height less than 2 seconds.

FAST NORM

10-10 50MSEC 1.00SEC

10-9 5MSEC 100MSEC

10-8 0.5MSEC 10MSEC

181

b. FPD/SFPD Switch (Figure 1)

Switch S2 is the FPD/SFPD slide switch, which must be set appropriately for the desired output，

either FPS or SFPD (square root PPD). FPD mode is the normal flame photometric detection mode

and SFPD is the square root FFD mode. To determine the correct output settings，refer to paragraph

182

2.1, Setting the FPD/SFPD Switch.

c. PMT Sensitivity Adjust Control (Figure 1)

The PMT (photomultiplier tube) sensitivity adjustment is screwdriver set from the pc board.

If the PMT has been replaced or if restoration of the original calibration setting is desired，the

sensitivity should be adjusted. It may also be adjusted to accommodate for a change of sensitivity due

to aging of tie tube and/or environmental damage e.g. overheating，or if a higher or 1ower signal

output level is desired. Adjust dark current noise (i.e., flame not lit) to give a noise level between 0.5

to 1 PA or 0.5 to 1% at 1 x10-10 A/MV. Refer to the FPD Test Chromatogram and operating

parameters in the Installation section of the manual.

Adjust the sensitivity by monitoring the FPD/SFP voltage display (FPS/SFP X xxx VOLTS) in the

detector Status section. The typical range of voltages to be expected is 350 to 650V.

d. Square Root Zero Adjustment

The square root zero adjustment is set from the top of the pc board with a screwdriver and used when

zeroing the baseline in the SFPD (square root) mode. Peak areas (component quantitation) will be

incorrect unless the baseline is adjusted close to zero. Therefore, Autozero must be enabled and used.

NOTE

Some column packing materials can cause detector response changes due to chemical

interaction with the samples. Consult your catalog for appropriate sulfur-analysis columns.

Use the following steps to set the square root zero adjustment. The flame should be 1it.

i. On the FPD pc board turn the square root zero potentiometer fully CCW and set the

FPD/SFPD switch to the SFPD position.

ii. Zero the printer/plotter by setting attenuation to INF (infinity) or zero recorder.

iii. Set range to 10 and attenuation to 256.

iv. From the fully counterclockwise position, turn the square root zero potentiometer slowly

clockwise until the baseline just reaches 5% above zero.

NOTE

Drift and excessive noise may cause the baseline to suddenly go to zero( baseline noise

disappears). When this happens, accuracy is considerably diminished. The square root zero

potentiometer will have to readjusted (CW), until the baseline again goes to 5%. This

adjustment is important and should be checked periodically, depending on the amount of

baseline drift.

v. The baseline is now properly adjusted for square root mode operation and the detection

system is ready for a sulfur analysis. Reset attenuation to 1024 and set the range to the sensitivity

required by the analysis.

5.2.1 Selecting the FPD/SFPD Switch Position

183

The FPD/SFPD switch setting is dependent on what the FPD will be used to detect, phosphorus or

sulfur-containing compounds.

Phosphorus Detection ( FPD Mode)

For detection of phosphorus-containing compounds, operate the FPD in only the FPD mode with the

phosphorus mode filter (03-905948-01).

Sulfur Detection (SFPD and FPD Modes)

Use the SFPD mode (sulfur mode filter, 03-905948-00) for corrections of square root response in

sulfur detection. The square root mode of operation is most usable for high concentration sulfur

analyses which have several large peaks. It is not generally very useful for trace analyses.

In the FPD mode the detector may be used for sulfur detection. Because of the input threshold

requirement of the square root circuit (see Square Root Mode Applications, paragraph 3.4), area

measurements are systematically too small at small peak heights. The correlation of error in area

versus peak height is shown in Figure 2.

In case of doubt about which sulfur detection mode to use, use the FPD mode and take the

square root later. Refer to para.3.2.5 for Optimization of the FPD for Sulfur

Response.

5.2.2 Using the FPD

184

When using the FPD together with a data system, data reduction can be made using either peak

heights or peak areas.

For peak heights, the FPD electrometer should be set to the FPD mode (see Figure 1), and the data

system should select the square root option. This will ensure the greatest accuracy in calibration.

For peak areas, the FPD electrometer should be set to SFPD (see Figure 1), and the data system

should select the peak area option. This should only be used for analyses of high concentrations of

sulfur. Measurements of sulfur-containing compounds at trace levels should use either peak heights

(as above) or use calibration standards and bracketing with both the FPD electrometer in the FPD

mode and the data system in the proportional to the square of the sulfur concentration—and thus

sulfur concentration is proportional to the square root of the signal.

5.3 OPERATION

5.3.1 Igniting the FPD Flame

Flame #2 is ignited directly by the ignitor coil, while Flame #1 is lit by back flash from Flame #2.

Use the following steps as a checklist for flame ignition:

Build the method. In the DETECTOR section, set the following:

a. Detector temperature (120℃≤TEMP≤350℃; 200℃ recommended)

b. Attenuation set to 8.

c. Range set to 10

d. Auto zero ON.

NOTE

The detector should generally be operated at a temperature at least 20℃ above the column

temperature and not below 120℃, to prevent water condensation. If the detector is operated at

a lower temperature, condensation in the detector assembly could lead to chemical

contamination with a resulting efficiency loss.

After the READY light goes ON, press [STATUS], then advance to the baseline display (FPD X

BASELINE xxxxx.xx MV A/Z). Note the value displayed for baseline. Autozero for the

detector should be ON.

Gas flows properly set at pneumatics panel (see Table 1).

Turn off the hydrogen supply and turn on both air supplies to the detector (air #1 and air #2) at

the pneumatics panel.

NOTE DO NOT use the square root mode on both the FPD

electrometer and the data system at the same time, as this

would only serve to take the square root of the FPD signal

185

WARNING

EXPLOSION HAZARD

Be sure that all hydrogen is purged from the system before igniting the FPD flame.

Press and hold [IGNITE A] (for DET A) or press [SHIFT] and hold [IGNITE B] (for DET B), as

appropriate, for approximately 3 seconds. Turn on the hydrogen supply to the detector while the

IGNITE key is pressed. The ignitor times out after 10 seconds.

Observe the baseline value displayed. Typically, the baseline will increase considerably,

depending on the column. If the flames continue to burn, the baseline value display will be

significantly greater than that noted in step 2.

TABLE 1

FPD GASES, PRESSURES, PURITY, AND FLOW RATES

GAS INLET PRESSURE


RECOMMENDED

FLOW RATE(ML/MIN)

Carrier: N2 or He 80 psig 99.998% 30 +/-1

Detector Gases:

Hydrogen

Air

40 psig

60 psig

99.995%

CGA Grade E

140+/-2

Air #1: 80 +/-2

Air #2:170+/-3

If a flameout is detected the Status light will blink. Press [STATUS]，then [ENTER] to display

all messages.

If no condensation is visib1y by holding a cool g1ass or metal object at the exhaust tube on the

detector tower and f the baseline value displayed on the printer/ p1otter or recorder returns to its

original value turn off the hydrogen at the pneumatics pane，go to step 2 and attempt to

reignite the flame, holding IGNITE for a slightly longer time.

If flames do not fight on second attempt，then go to the GC Configure table and turn OFF the

detector. Check gas flows and all cable connections. Refer to the Diagnostics/Troubleshooting

section for further assistance.

5.3.2 FPD Operational Recommendations

When initiating operation of an FPD，use a preconditioned column and septum. Other operational

recommendations are given for optimum detector performance.

Column Selection

Some sulfur and phosphorus compounds interact with certain column-packing materials. Consult

186

with the local dealer.

Heatup / Cooldown Precautions

CAUTION

When operating with an FPD, always have the instrument top cover and the detector cover in

place to assure proper air flow over the detector tower(s). Accumulation of heat in the top of the

GC can cause deterioration of detector performance and shorten the life of the PMT.

Before shutting off the GG，leave the carrier gas flowing and 1et the instrument run for 15 minutes

with all heat zones turned off. This avoids overheating the PMT by accumulation of trapped column

oven heat.

PMT Care

Performance of the FPD photomultiplier tube (PMT) is affected by overheating or overexposure to

light, particularly if the high voltage is on. Normal operating range for the FPD is 120℃ to 350℃.

Turn power to the PMT off when not in use, i.e., oven weekends or when not used for long periods of

time.

NOTE

Operation at temperature above 250℃ requires replacement of the FPD adapter O-ring if the

detector is removed.

Operation at detector temperatures above 350℃ tend to degrade detector performance and

shorten the useful life of the PMT.

A protection circuit monitoring current protects the PMT from exposure to bright light while the

power is on and the signal cable connected. To avoid damaging the PMT by disconnecting the signal

cable whi1e the PMT power is on, turn power to the PMT off (set FPD to OFF in GC Configure

table) or always disconnect the high voltage cable before disconnecting the signal cable and

reconnect the signal cable before reconnecting the high voltage cable.

CAUTION

The FPD must always be OFF when the PMT cover is removed, as high voltage is present.

Injection Considerations

Because of the FPD’s dual-flame design relate relatively large sol vent volumes may be injected into

the GC. Typically，solvent volumes in excess of 50 ul can be injected without causing the detector

flame to be extinguished or overburdened with solvent. When large solvent peaks pass through the

detector, Flame #1 may be momentarily extinguished, but Flame #2 remains burning and reignites

Flame #1 when the solvent peak has passed.

Optimization of the FPD For Sulfur Response

a. Turn off detector in GC Configure table (turns detector high voltage off). Remove the instrument

top covers and the phosphorus-mode filter (03-905948-01). Install the sulfur-mode fi1ter

(03-905948-00). (Reference para.6.3, Optical Filter Changing.) Replace instrument top covers and

turn detector on.

187

b. With standard test column install and flow rates and temperatures set per the Initial Operating

Parameters table in the Installation section, with attenuation at 8 and range set to 10-10, adjust the

FPD voltage per paragraph 2, PMT Sensitivity Adjust Control, if it is not in the typical range of

voltages to be expected (350 to 650v), as displayed in the detector STATUS section (FPD/SFP X xxx

VOLTS).

c. Inject 1u1 of FPD test sample. The chromatogram shout d resemble that should in the

Installation section. If only a solvent peak is produced, skip to step 5.

d. Increase hydrogen flow slightly, then inject again. Increasing hydrogen flow will improve

sensitivity to sulfur and also sulfur/carbon selectivity up to the point where the lower flame dose not

reignite after being extinguished by the solvent.

When this point is reached, only a solvent peak will be produced, with no sign of the pentadecane or

sulfur components.

e. Reduce hydrogen flow slowly and watch for a sharp step increase of 5-8% of full scale in the

background current (baseline). This step is caused by reignition of the lower flame. This is the

optimum hydrogen flow rate for sulfur response. Maximum sensitivity and selectivity are

produced by the highest hydrogen flow rate that will still permit reignition of the lower flame.

With the hydrogen flow optimized, the reignition spike should be detectable on the side of the solvent

peak. The position at which the spike occurs will vary upscale or downscale with decrease or increase

in hydrogen flow, respectively. The ideal position is about 2% above baseline; this procedure may be

used for fine tuning the hydrogen flow rate.

Detector Range Selecting

The available range of sensitivity for FPD output mode is from 1024 10-8 to 1 10-10 A/mV. The

usable range of sensitivity setting in the SFPD mode is from 256 to 1024 with ranges

of .

The output signal voltage to the recorder of printer/plotter is 1 mV ful1-scale. For the normal (FPD)

setting of the FPD/SFPD switch, the highest possible setting of the range which does not cause the

amplifier to saturate on sample peaks should be used. If the FPD/SFPD switch is set to SFPD, the

recommended procedure is to set attenuation to 1024, then set the range to provide maximum peak

heights between 70% and 100% on the printer/plotter or recorder.

5.3.3 Detector Response

The sensitivity for phosphorus is usually expressed directly in terms of nA/(ngP/sec), where as the

sensitivity for sulfur is expressed in terms of nA/(ngS/sec)2 because of the square-law relationship

188

between peak height and flow rate (by weight) of sulfur. (See the Installation section for the FPD

Test Chromatogram.)

Figure 3 shows plots of the FPD sensitivity in both phosphorus and sulfur modes in FPD mode Data

are shown for three compounds: one contains only phosphorus; one contains both phosphorus and

sulfur; and one contains only sulfur. With the phosphorus mode filter installed, tributy1 phosphate

and methy1 parathion exhibit the same sensitivity except at the very highest sample amounts. The

slope of the phosphorus sensitivity plot is l.0, meaning that the response is linear, and the linear range

exhibited is approximately 105 0f sample amount. Minimum detectable quantity of phosphorus per

second is less than l pgP/sec.

With the sulfur-mode filter installed and the FPD mode used, methyl parathion and hexanethiol also

exhibit exactly the same sensitivity except at high quantities of sample. The slope of the sulfur

sensitivity plot is 2.0, meaning that the sulfur response follows a pure square-law dependence for

these compounds. The sulfur response extends over a range of 103 0f sample amount, and the

minimum detectable quantity per second is less than 10-1 ngS/sec. Although greater sensitivities can

be obtained with alternative fuel gas flow rates, a deviation from a pure square-law response will

occur. Sensitivity and response range in square root output mode are discussed in paragraph 3.4,

SFPD Mode Applications.

Selectivity

In the phosphorus mode, selectivity of phosphorus with respect to carbon is greater than 5 105 0n a

189

weight basis. This means that it takes more than 500 μg of carbon to produce the same light

intensity through the phosphorus mode filter as one nanogram of phosphorus. This phosphorus

selectivity with respect to sulfur is variable depending on the amount of sulfur present. This is

because the sulfur signal varies as the square of the amount of sulfur, while the phosphorus signal

varies linearly with the amount of phosphorus. Using the phosphorus mode filter the

phosphorus-to-sulfur selectivity varies from 5 104 at very low levels of sulfur to about 50 at very

high levels of sulfur.

In sulfur mode, selectivity of sulfur with respect to carbon or phosphorus similarly varies because of

the square law relationship of signal to sulfur quantity. Using the sulfur mode filter, the sulfur

to-carbon selectivity varies from greater than 106 at high sulfur content to about lO3 at low sulfur

content, and the sulfur-to- phosphorus selectivity varies from greater than 104 at high sulfur content

to about 10 at low sulfur content.

Sensitivity/Detectivity Relationship

Detectivity of the detector is defined as the ratio of twice the noise to the sensitivity of the detector.

As indicated in the discussion of sensitivity, the units for phosphorus and sulfur sensitivity are

different, due to the square law relationship of detector signal amplitude to sulfur amount. Similarly,

there are individual definitions for the detectivity of phosphorus and sulfur. The following

equations give the relationships between sensitivity (S) and detectivity (D).

Effects of Gas Flow Rates

Detector performance is affected by the flow rates of each of the gases supplied to the detector flames.

The recommended flow rates given in Table l have been selected to give the best combination of

sensitivity, selectivity, and signal-to-noise ratio while maintaining a positive combustion environment

for the flames. Figures 4 through 6 illustrate the effect of changes in gas flow rates.

Effects of Gas Flow Rates (cont.)

Definitions for Figures 4 through 6:

Ip = Phosphorus response current

IS = Sulfur response current

Ic = Hydrocarbon response current

190

IB = Flame background current

For sustained operation of both flames in the dual-flame burner, the flow rates must be maintained in

the following ranges:

Air #1: Between 70 and 120 ml/min

H2: Between 70 and 150 ml/min

Air #2: Greater than 160 ml/min

192

5.3.4 SFPD Mode Applications

The FPD PCB contains a circuit which performs square root processing of the square law detector

signal when the FPD/SFPD switch is in the SFPD position. The result is a linearized sulfur-analysis

output signal to the printer/plotter, computer, and/or integrator, which can be analyzed as if the

detector response were linear. This mode is intended for peak area processing using

triangulation on a peak.

NOTE

Refer to para. 2.2 for a discussion on using the FPD or SFPD switch position with a data system

The FPD PCB square root circuit performs the square root operation on the total detector signal,

therefore any baseline offset is treated in the same manner as the sample peak signal, and the

processed output signal represents the square root of the sum of the sample peak height and any

baseline offset, i.e., Square Root Output = . Because of this characteristic, always

operate with no baseline offset in order to obtain a linear peak-height response in SFPD mode.

Another significant characteristic of the square root circuit is that, like most signal processors, it

requires some specific minimum signal amplitude, below which any signal (or noise) is ignored. To

minimize the percentage of the detector signal that is cut off by the square root circuit input threshold,

the signal through the FPD amplifier to the square root circuit must be kept as large as possible. This

is accomplished by using as high a sensitivity RANGE setting as possible, combined with a high

attenuation of the output signal. With attenuation set to 1024, the level at which the signal and noise

cutoff occurs is approximately 1% of full-scale deflection.

Attenuation settings used in SFPD mode should be limited to the highest three positions (1024, 512,

and 256). When the square root output is selected, the range values are , , and .

The 512 and 256 attenuations may be used for increased sensitivity; however, attenuations below

256 should not be used in SFPD mode, since the portion of the detector signal below the square

root circuit threshold represent too large a percentage of the deflection scale.

Sample peaks and/or noise signals below the square root processor threshold (approximately l% of

full-scale deflection at 1024 attention) will be ignored and will not appear on the chromatogram. All

sample peaks with heights greater than the processor threshold will appear and their peak heights will

be correct; however, the peak Shape below the threshold level on all peaks will be distorted and the

baseline-to-peak transition will be abrupt because of the turn-on/turn-off effect of the square root

processor.

The closer the top of the peak comes to the threshold level, the greater the distortion of peak shape

and thus the less accurate the peak area measurement.

193

Correlation between the arbitrary output % deflection scale in SFPD mode (with attenuation at 1024)

and output current in direct mode is shown in Figure 7.

5.3.5 Increased Sulfur Sensitivity Mode

For some sulfur compounds which do not have hydrocarbon interference, the FPD can be operated in

an alternate mode which provides greater sensitivity for certain types of sulfur compounds, greatly

reduces phosphorus response, and has virtually no hydrocarbon response; however, it decreases

linearity (or square law relationship) of the detector and increases the probability of response

quenching by the solvent and other compounds. Thus, the detector response characteristics become

more dependent on the quantity and composition of the sample injected. Hence, comparison with

known standard samples is required for accurate quantitative work.

Conversion to the increased sulfur sensitivity mode is accomplished by interchanging the air and

hydrogen flows into the detector. To facilitate this interchange, unions are provided in the pneumatics

cabinet on both the air and hydrogen lines.

194

Conversion to the Increased Sulfur Sensitivity Mode

For the second hydrogen stream (used with increased sulfur sensitivity mode only), the air and

hydrogen lines are interchanged and the air #2 valve is replumbed for the hydrogen #2 stream Refer

to Figures 8a and 8b for plumbing schematics.

1. Turn off gas supplies and release any accumulated pressure in the instrument lines.

2. Disconnect the FPD air #1 0utlet line, at the union (A) which has a red tag. Disconnect the

hydrogen #2 0utlet line, at the union (B).

3. Connect the hydrogen line at union (B) to the air #1 0utlet. This is now the H2 #2 line when

connected to the FPD.

4. Connect the air outlet line at union A to the hydrogen line (previously union B outlet). This is

now t-he air line. Tighten all fittings.

5. Remove the .062'1 diameter pin from union (D) to cap the air #1 inlet line at union (C).

6. To supply hydrogen to the air #2 make-up valve (black cap), connect the air #2 'inlet line at the

union {C) to (D), H2.inlet, and cap the end coming from the air valve, using the union and cap

from the previous step.

CAUTION

Operation must mark valves appropriately when operation in the high sulfur sensitivity mode,

as two separate and independent valves must be closed to shut off hydrogen flow.

7. Connect the #2 hydrogen outlet line (D) to the union (E) going into the air #1 valve. Install

FPD label at this detector make-up valve position. Tighten all fittings and plug all unused ports.

8. Turn on gas supplies and carefully leak check at unions and capped ends that were changed.

NOTE

It is advisable to label the make-up valve as carrying hydrogen. Use removable tape so that

label can be taken off if system is restored to standard operation.

9. Set flows as follows:

Air #1: 105 ml/min H2 #2: 150 ml/min

H2 #1: 110 ml/min

10. Turn both hydrogen flows OFF then press [IGNITE A] or [SHIFT] [IGNITE B], as appropriate,

and after 3 seconds, turn hydrogen #1 ON. Verify flame ignition by holding a cool metal or glass

object at the detector tower exit tube. Condensation assures that flame is lit. Turn on H2 #2.

NOTE

Ignition will not occur with hydrogen as the only gas in the detector tower.

196

11. Set flows as follows:

Air #1: 105 ml／min H2 #2: 150 ml/min

H2 #1: 110 ml/min

12. Turn both hydrogen flows OFF then press [IGNITE A] or [SHIFT] [IGNITE B], as appropriate,

and after 3 seconds, turn hydrogen #1 ON. Verify flame ignition by holding a CO0l metal or glass

object at the detector tower exit tube. Condensation assures that flame is lit. Turn on H2 #2.

NOTE

Ignition will not occur with hydrogen as the only gas in the detector tower.

5.4 FPD PNEUMATICS

All Series GCs equipped with FPD's are factory tested with the flow rates listed in Table 1. These

flow rates should be used as a starting point when checking flow rate adjustments at the pneumatics

panel before detector use.

Gas flow rate measurement must be made with the detector fully assembled and secured in place.

Flow rate measurement using the soap bubble flow meter is detailed in the Installation section of

this manual. Refer to the installation section for recommended filters for specific gases and for

packed column or capillary column applications.

NOTE

Gas filters should be tightly capped when not in use. Prolonged exposure to room air will

degrade their performance.

WARNING

EXPLOSIVE GAS

The FPD operates at hydrogen flow rates up to 260ml/min. To avoid an accumulation of

hydrogen gas and possible fire or explosion hazard, always turn off hydrogen flow when

column is removed or when the detector is not being used.

5.5 INSTALLATION/DISASSEMBLY

If it is necessary to remove the detector components for inspection, cleaning, parts replacement, or


FPD and the detector oven.

It is not necessary to remove the FPD to change optical filters (para.6.3), to replace the

photomultiplier tube (para.6.5), or to replace the igniter (para.6.6). It is not necessary or desirable to

loosen or remove the FPD adapter plate when removing the detector for cleaning or repair (para.6.1).

197

5.5.1 FPD Disassembly

Figures 9a and 9b show the installation of the FPD and its cable connections. Figures l0a and l0b

are FPD pneumatic schematics. Refer to the appropriate figures for your GC. Figure 11 is an

exploded view of the FPD. Refer to these figures while following the disassembly procedure below.


1. Turn off detector.


WARNING

EXPLOSIVE GAS

The FPD operates at hydrogen flow rates up to 260ml/min. To avoid an accumulation of

hydrogen gas and possible fire or explosion hazard, always turn off hydrogen flow when

column is removed or when the detector is not being used.

WARNING

HOT SURFACES

To avoid burns and/or shock hazards, be sure the FPD is cool and the power is off before

removing cables or detector.

3. Disconnect the high voltage cable, then the signal cable from the PMT housing (Figure 9a or 9b).

CAUTION

The circuit for the PMT is disabled when the signal cable is disconnected. To avoid the

possibility of ever damaging the PMT by disconnecting the signal cable while the PMT power is

on, always disconnect the high voltage cable before disconnecting the signal cable and

reconnect the signal cable before reconnecting the high voltage cable.

4. Disconnect the igniter cable from the detector tower.

5. Remove the two long screws holding the detector tower to the FPD adapter plate and lift the

entire detector assembly from the GC. This exposes the flame tip assembly.

6. Remove the flame tips, if desired, but do not loosen the adapter plate unless the FPD is to be

removed from the instrument (e.g. for installing a different type of detector.)

7. Detector components are detailed in Figures 11 and 12. Specific disassembly procedures for

cleaning the tower and optical components and for replacing the PMT and igniter are detailed

in paragraph 6.

200

5.5.2 FPD Adapter Plate Removal/Reinstallation

The FPD adapter plate should not be removed from the instrument unless the FPD is to be removed

(to install another detector) or unless the detector oven is to be removed.

Whenever the adapter plate is loosened, or removed and reinstalled, the aluminum seal washer

between the detector base and the adapter plate must be replaced. Failure to do so may cause gas

leakage with a resulting loss in chromatographic reproducibility.

To remove the adapter plate:\

1. Remove the flame tips from the detector base (Step 6 in previous paragraph).

2. Remove the two screws holding the adapter plate to the detector base (Figure 11), and then lift

the adapter plate and the aluminum washer from the detector base.

If the adapter plate is to be taken out of the GC to install a different detector, the air #2 lines must be

disconnected from the make-up valve at the O-ring union. Guide the tubing and the adapter plate out

of the instrument and store with the FPD.

If the detector is only being removed to gain access to the detector oven, place the adapter plate on a

clean uncontaminated surface and proceed to paragraph 5.3.

To reinstall the adapter plate:

1. Install the flame tips as described in paragraph 5.4.

2. Place a new aluminum seal washer on the shoulder of the detector base.

3. Place the adapter plate over the flame tip, orienting the plate so the gas line passes through the

slot in the side of the detector oven cover. Secure the adapter plate to the detector base with the

two 8-32 x 5/8-inch screws, alternately tightening the two screws.

NOTE

A scored or deformed O-ring on the adapter plate can cause gas leakage or erratic gas flow.

Operation at temperatures above 250℃ will deform O-rings. The seal remains gas-tight

but the O-ring must be replaced upon reassembly. Refer to para.64 for O-ring replacement.

4. Before installing the detector on the adapter plate, measure the carrier gas flow out of the flame

tip. This measurement will be used for a leak check of the seal at the aluminum seal washer

after the detector has been installed (para.5.4).

202

5.5.3 Detector Oven Removal and Reassembly

If it is necessary to remove or replace the probe or heater cartridge, disassembly of the detector oven

should proceed as detailed below:

WARNING

DANGEROUS VOLTAGES


power and allow it to cool before connecting or disconnecting cables.

1. Turn instrument power OFF and check that instrument is disconnected from ac line power.

Remove the high voltage cover Refer to Figure 11. Disconnect the heater cartridge and probe

harness from J71 along the top of the Temperature Controller (TEMP) PC Board.

2. Turn off both air and hydrogen and disconnect from their respective connections at the air and

hydrogen valves.

3. Remove detector per paragraph 5.1.

4. Remove the two 8-32 screws from the detector base top flange.

5. Lift the detector base and remove it from detector oven.

6. Remove four 8-32 screws from the ionization oven cover and remove detector oven and

attached cover from the instrument.

7. Invert detector oven. On each side of the cover are 2 screws and lock washers holding the cover

to the oven. Remove the screws, lock washers, and the spacers between the cover and the

oven.

203

8. Remove detector oven from cover. Carefully withdraw heater/probe assembly from oven

base.

9. Insert replacement heater and probe fully into detector oven base.

10. Reassemble and make connections by reversing above procedure. When reinstalling high

voltage cover, make sure tab on cover is fully depressing interlock switch (S l) on Power Supply

PCB.

5.5.4 FPD Reassembly

Refer to Figures 9a or 9b through 12 for FPD reassembly. The adapter plate should be installed per

paragraph 5.2, and the detector should be completely assembled.

1. If the flame tips were removed without removing or loosening the adapter plate, insert

the #1 flame tip, with attached ferrule, through the adapter plate into the detector base.

Install the ferrule-backing washer and the #2 flame tip (Figure 11). If the #1 flame tip is to be

replaced, it should be inserted as far as it will go into the detector base, then the ferrule should

be placed down over the #1 flame tip, followed by the ferrule-backing washer and the #2

flame tip. Tighten the #2 flame tip finger-tight, then an additional l/8 to l/16-turn with a

wrench.

CAUTION

Do not overtighten the flame tip, as this will compress the ferrule into the detector base and

#1 flame tip and may damage components.

2. Check the adapter plate O-ring for deterioration and replace if necessary

NOTE

A scored or deformed O-ring on the adapter can cause gas leakage or erratic gas flow.

Operation at temperatures above 250℃ will deform O-rings. The seal remains gas-tight

but the O-ring must be replaced upon reassembly.

3. Place the detector tower on the adapter plate and secure with the two 8-32

____________________________________________________________________________

_

4. Connect the signal, high voltage, and igniter cables to the detector. Refer to Figure 9a or 9b.

5. Recheck the gas flows per Table l. The carrier gas flow measurement should be within 5% of

the value obtained at the flame tip in paragraph 6.2 (3). If it is not, the seal at the aluminum

seal washer is probably leaking. (Check that the adapter plate is tight; replace the aluminum

seal washer if necessary.

6. After detector seal is satisfactory, replace high voltage cover, instrument top cover, and detector

cover.

204


CAUTION

Turn instrument power OFF when removing or installing pc boards

To remove the FPD PC Board:

1 Turn instrument power OFF. Failure to do so may allow accidental contact with dangerous

voltages or circuits when removing or installing DC boards or damage the board or GC.

2. Disconnect high voltage cable and signal cable from detector.

3. Turn yellow connector cam clockwise 900 to release board.

4. Holding metal can, ease pc board straight up and out of the plastic guide slots in cabinet. Do

not touch edge connectors. Place pcb in clean antistatic bag when not in the GC.

Install DC board by inserting into card guide on the right and then lowering into the connector on the


board. Close connector cam. Reconnect cables to detector. Look to be sure connectors mate.

5.6 MAINTENANCE

The FPD requires no maintenance unless there is deterioration of sensitivity or a loss of

reproducibility in the chromatograms. Use the following procedures for corrective maintenance

and/or parts replacement.

5.6.1Detector Cleaning

During normal operation of the FPD, there is very little build up of contaminants inside the detector

tower. Even a heavy accumulation of contaminants will not affect the performance of the detector,

except for a possible loss of light transmission through the tower window (para.6.2). If a build up is

found while other maintenance is being performed on the detector, it may be removed by scraping the

inside of the tower. CAUTION: Take care to avoid scratching the detector window.

WARNING

HAZARDOUS CHEMICALS

The upper flame tip sometimes becomes contaminated, causing baseline instability on the more

sensitive ranges. Clean by heating in 50% nitric acid for 20 minutes at 50℃ under a fume hood

in a well-vented area. Exercise appropriate precautions when handling nitric acid.

5.6.2 Tower Window Cleaning

The presence of deposits on any of the optical components of the detector will reduce the

transmission of light and thus affect the detector sensitivity. Avoid leaving contamination (e.g.,

fingerprints) on the detector window, lenses, optical filters, and PMT.

A slight accumulation of contaminants may occur on the inside of the window in the detector tower

during normal operation of the FPD; therefore. the window should be checked occassionally and

205

cleaned or replaced if not still clear. (NOTE: This is not the only possible cause of reduced

detector sensitivity. Also refer to the Diagnostics/Troubleshooting section.)

Removing the Tower Window for Cleaning

1. Remove the detector tower from the GC per paragraph 5.1.

2. Remove the four 4-40 D_Dd__________ðáϨϨ________________

____________________________________________________________________________

_housing section of the detector from the tower section.

3. Remove the three 4-40

____________________________________________________________________________

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4. Clean the window using acetone and a lint-free cloth.

While at this stage of disassembly, check the outside of the lens assembly and clean the

surface with acetone if necessary. It is not normally necessary to disassemble the lens

assembly; however, if the lenses are removed from the detector, refer to Figure 11 for

orientation when reinstalling the components.

Reinstalling the Tower Window

1. Inspect the window, O-ring, and Teflon gasket. Replace any defective part. A spare window

(P/N 28-000424-00) and spare 0-rings (part numbers 03-905960-00; -01; and -05) are supplied

in the FPD Start-Up Kit (Kit Number 03-908442-90).

2. Reassemble the window assembly in the sequence shown in Figure 10: Teflon washer, window,

O-ring, collar plate assembly, and collar plate adapter. Be sure to orient the collar plate

assembly and collar adapter correctly, as indicated by alignment of the screw holes.

3. While holding these components in place, insert each of the three 4-40

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206

4. Before reconnecting the PMT housing to the collar plate assembly, check the shield tube

O-rings for deterioration or breakage. Replace if necessary (para.6.4).

5. Place the shield tube over the O-ring on the lens assembly, then reinstalls the four 4-40 x

l/4-inch screws holding the collar plate assembly to the hexagonal mounting bars.

6. After tightening the four screws, slide the shield tube over the O-ring on the collar plate

assembly. Push the tube toward the tower until it fits flush against the collar plate assembly.

7. Reinstall detector into GC

5.6.3 0ptical Filter Changing

Two optical filters are supplied with the FPD: one for phosphorus mode operation; one for sulfur

mode operation. To change from one mode of operation to the other, only the optical filter needs to

be changed. Gas flow rates are the same for both modes of operation.

Each filter is installed in a holder block for ease in changing from one operating mode to the other.

The phosphorus mode filter assembly (P/N 03-905948-01) is shipped in the detector. The sulfur

mode filter assembly (P/N 03-905948-00) is packaged separately.

0ptical Filter Changing (cont.)

The phosphorus filter ("P" label) appears pink with a greenish tinge and has a reflective coating; the

sulfur filter ("S" label) looks like a disc of black glass. NOTE: The interference coating on the

phosphorus filter is susceptible to damage by moisture and therefore should be stored in a dry

environment. If there is any deterioration of the coating, it will first become apparent as a

discoloration around the edges of the filter. If deterioration occurs, the filter should be replaced.

To change the optical filter:

1. Turn off detector and disconnect high voltage power cable and signal cable from the detector

tower. Disconnect from line power. The gases to the detector may be left on and the flames

may remain burning.

WARNING

HIGH VOLTAGES PRESENT

Dangerous voltages are exposed when the PMT housing is accessed. Be sure the instrument is

disconnected from line power before servicing the PMT.

2. Remove instrument top covers.

3. Remove the four corner screws from the top of the PMT housing and lift the housing top plate,

with attached filter assembly, from the detector.

4. Remove the two screws holding the filter assembly to the PMT housing top plate.

5. Attach the other filter assembly to the PMT housing top plate with the two mounting screws

and install the assembly in the detector by reversing the removal procedure. For the

phosphorus mode filter, the reflective coating should face toward the flame. Be sure the

light-sealing gasket for the filter assembly is properly in place.

5.6.4 O-Ring Life and Replacement

207

There are five O- rings used in the FPD assembly (Figure 10). If the FPD is continuously or

frequently operated at or near its maximum specified operating temperature (420), the O-rings

associated with the detector tower will deform. (O-rings begin to deteriorate at temperatures above

2500C). However, performance of the detector will probably not be affected unless the detector is

disassembled and reassembled without replacing the O-rings. The only seal that is likely to affect

performance is the one between the FPD adapter plate and the detector tower. A gas leak at this

point could affect the reproducibility of chromatograms by causing a change in the ratio of gases

supplied to the flames.

Any of the O-rings that are exposed to observation during disassembly for any reason should be

inspected and replaced if deteriorated, broken, or scored. Spare O-rings for the adapter-to-tower

seal and for the tower window seal are supplied in the FPD Start-Up Kit (P/N 03-908442-90).

Additional O-rings may be ordered by using the following part numbers:

Adapter-to-tower O-ring P/N 03-905960-00

Tower window O-ring P/N 03-905960-01

Shield tube O-ring (narrow) P/N 03-905960-02'

Shield tube O-ring (wide) P/N 03-905960-03

Exit tube plug O-ring P/N 03-905960-04

Access to the adapter-to-tower O-ring seal is easily gained by removing the tw0 2-3/4-inch screws

that hold the detector assembly to the adapter plate.

Replacement of the O-rings in the optical system is detailed in paragraph 6.2. Replacement of the

exit tube assembly O-ring is detailed in paragraph 6.6.

5.6.5 Photomultiplier Tube (PMT) Replacements

The PMT In the detector will normally function properly for a long period of time if not Overheated

and if not overexposed to light while voltage is applied (see PMT Care, paragraph 3.2.3). As the

tube ages, its sensitivity may slowly decrease, therefore the sensitivity of the tube should be

periodically checked (as described in paragraph 2, OPMT Sensitivity Adjust Control )and

readjusted if necessary.

If the PMT is found to be defective, replace it as follows:\

1. Turn off detector and disconnect high voltage cable.

WARNING

HIGH VOLTAGES PRESENT

Dangerous voltages are exposed when the PMT housing is opened. Be sure the high voltage is

turned OFF before servicing the PMT.

2. Remove the four corner screws in the top of the PMT housing and remove the top plate with its

attached filter holder.

3. Remove the defective PMT by pulling up on it while slightly rocking it back and forth.

208

4. Make sure the side of the PMT facing the lens assembly is clean. If necessary, wipe it with a

clean lint-free cloth moistened with acetone.

5. Align the base pins of the new PMT with the holes in the tube socket and insert the tube. Press

the PMT firmly into the socket until it bottoms out.

Photomultiplier Tube (PMT) Replacements (cont.)

1. Reinstall the housing top plate, making sure that its gasket is properly in place, and secure the plate with the four screws.

2. After replacing the PMT, check the sensitivity adjustment as described in paragraph 2, PMT Sensitivity Adjust Control.

5.6.6 Igniter Replacement

The FPD Igniter is a resistance coil mounted above the second flame in the detector. If the detector flame will not light according to the procedure given in paragraph 3.1 (Igniting the FPD Flare), check the igniter coil as follows:

1. Turn off ac power. Turn off hydrogen and air. Carrier gas should be left on.

2. Remove detector cover and instrument top cover.

3. Allow top of detector and the exit tube to cool to handling temperature.

4. Remove the two screws holding the top clamp on the FPD tower (Figure 11) and remove the top clamp and the exit plug assembly.

5. Turn on instrument power. Press and hold [SHIFT] [IGNITE B] for about 5 seconds while checking for ignitor coil glow through the hole in the top of the detector tower. If the coil glows red, the lack of flame ignition is due to some other cause, such as incorrect gas flows.

If there is no igniter coil glow, turn off instrument power and check igniter cable and cable connections (Fig. 9) before replacing igniter. Check continuity of the coil before removing the igniter from the detector tower: resistance between the two terminals of the igniter connector should be very low (<3 ohms).

6. Replace a defective igniter as follows

a. Carefully unscrew igniter from detector tower.

b. Place a new O-ring (supplied) over the igniter threads. Wrap threads of new igniter with Teflon tape being careful not to disturb igniter coil.

c. Screw new igniter into tower until the flange on the connector stops against the tower wall.

d. Check igniter operation as described in step 5.

e. Turn off instrument power and reinstall the exit plug assembly with the exit tube pointing toward the front of the GC. Secure top clamp to detector tower with two 8-32 D208Dd208208208208208208208208208208

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