local probes
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STI Field Application NoteEccentricity TSI
Shaft Eccentricity plays a very important role as part of a Turbine Supervisory Instrumentation
(TSI) System on large steam turbines and should be included in retro-fit plans when at all possible.
Operators use eccentricity measurements to
determine when a combination of slow roll and
heating have reduced the rotor eccentricity to the
point where the turbine can safely be brought up
to speed without damage from excessive
vibration or rotor to stator contact.
Eccentricity is the measurement of Rotor Bow at
rotor slow roll which may be caused by any or a
combination of
Fixed mechanical bow1.
Temporary thermal bow2.
Gravity bow3.
In extreme cases of thermal/gravity bow, caused by a sudden trip of the unit and failure of the
turning gear to engage, the rotor may be positioned and stopped 180o out of phase (bow up) to
allow gravity to work entirely on the bow and substantially shorten the time required to reduce the
bow.
Eccentricity is measured while the turbine is on slow roll (1 to 240 RPM below the speed at which
the rotor becomes dynamic and rises in the bearing on the oil wedge) and requires special circuitry
to detect the peak- to-peak motion of the shaft. This is accomplished using circuitry with long
update times selectable between 20 seconds (> 3 RPM) and 2 minutes (
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Turbine owners who are retrofitting existing eccentricity systems supplied by the OEM or others will
mount the eccentricity transducer at the same location as the original installation. In many cases
only minor modifications to the existing bracket are required. Using the same location has several
advantages and simplifies installation.
OEM's original installation as a rule included an eccentricity collar or other good target for an
Eddy Probe System.
1.
Eddy Probe eccentricity measurements will agree closely with the original OEM supplied
system as the measurements will be taken at the same location.
2.
Operators will need less training on how to interpret the new systems measurements as
they will be basically the same.
3.
Eccentricity historical data will be valid.4.
Existing brackets may be modified.5.
Case or standard penetration for cable may be reused with minor modification.6.
Eccentricity is normally measured P/P (Peak to Peak) to agree with previously established
conventions. The actual excursion from shaft centerline caused by bow would be one half that
measurement or the 0/P (Zero to Peak) measurement. The Turbine Supervisory Instrumentation
may be calibrated in either fashion to suite the users requirements.
Theory of Operation
Eddy Current Transducers work on the proximity theory of operation. A system consists of a
matched component system: a Probe, an Extension Cable and an Oscillator /Demodulator (driver).
A high frequency RF signal @2 mHZ is generated by the Oscillator/Demodulator, sent through the
extension cable and radiated from the Probe tip. Eddy currents are generated in the surface of the
shaft. The driver demodulates the signal and provides a modulated DC Voltage where the DC
portion is directly proportional to gap (distance) and the AC portion is directly proportional to
vibration. In this way, an Eddy Current Transducer can be used for both Radial Vibration and
distance measurements such as Thrust Position and Shaft Position.
Special Considerations
Mounting OrientationAll vibration transducers measure motion in their mounted plane. In other words, motion either
directly away from or towards the mounted Eddy Probe will be measured as eccentricity.
For eccentricity measurements it is recommended that the transducer be mounted vertically. As
most eccentricity sensors are internally mounted and are not visible from the outside of the
machine whatever the angle of orientation is finally chosen it is very important that the mounting
Field Application Note: Eccentricity TSI http://www.stiweb.com/appnotes/Eccentricity-TSI.html
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location be documented for future reference.
Linear RangeSeveral versions of Eddy Probe Transducers are available with a variety of Linear Ranges and body
styles. In most cases, a sensor with a linear range of 90 mils (0.090") is more than adequate for
Eccentricity measurements.
Model Range Output Size
CMSS65 90 mils 200 mV/mil 1/4"x28 UNF 1" to 5" Length
CMSS68 90 mils 200 mV/mil 3/8"x24 UNF 1" to 9" Length
Target Material/Target Area
Eddy Current transducers are calibrated at the factory for 4140 Steel unless specified otherwise. As
Eddy Probes are sensitive to the permeability and resistivity of the shaft material, any shaft
material other than 4000 series steels must be specified at the time of order. In cases of exotic
shaft material a sample may need to be supplied to the factory.
Mechanical RunoutEddy Current transducers are also sensitive to the shaft smoothness for Eccentricity. A smooth (64
micro-inch) area approximately 3 times the diameter of the probe tip must be provided for a
viewing area.
Electrical RunoutSince Eddy Probes are sensitive to the permeability and resistivity of the target material and the
field of the transducer extends into the surface area of the shaft by approximately 15 mils (0.015"),
care must be taken to avoid non homogeneous viewing area materials such as Chrome.
Another form of electrical runout can be caused by small magnetic fields such as those left by
Magna-fluxing without proper degaussing.
Perpendicular to shaft centerlineCare must be exercised in all installations to insure that the Eddy Probe is mounted perpendicular
to the shaft center-line. Deviation by more than 1-2 degrees will effect the output sensitivity of the
Probe.
Transducer (Probe) side clearancesThe RF Field emitted from the probe tip of the transducer is approximately a 45 conical shape.
Clearance must be provided on all sides of the Probe tip to prevent interference of the RF Field.
Care must also be taken to avoid collars or shoulders on the shaft that may thermally "grow" out
from under the Probe tip as the shaft expands.
Eddy Probe tip to tip clearancesAlthough Eddy Probe tip to tip clearances are not normally an issue on most machines, it should be
noted that the probes radiate an RF Field larger than the probe tip itself. As an example, SKF-CM
CMSS65 and 68 Eddy Probes should never be installed with less than one (1) inch of Probe tip to tip
clearance. Larger probes require more clearance. Failure to follow this rule will allow the driver to
create a "beat" frequency which will be the sum and difference of the two driver RF frequencies.
System Cable Length and Junction BoxesEddy Probe Systems are a "tuned" length, and several system lengths are available. System length
is measured from the probe tip to the Oscillator/Demodulator, and is measured electrically which
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can be slightly different than the physical length. For example, the Model 403 is available in 9, 20,
and 30 foot system lengths. Care must be taken to insure that the proper system length is ordered
to reach the required Junction Box.
Grounding and NoiseElectrical noise is a very serious consideration when installing any vibration transducer, and special
care needs to be taken to prevent unnecessary amounts of noise. As most plant electrical noise is
at 60 HZ, and many machine running speeds are also 60 HZ, it is difficult to separate noise from
actual vibration signal. Therefore, noise must be kept to an absolute minimum.
Instrument WireA 3-wire twisted shielded instrument wire (ie; Belden #8770) is used to connect each
Oscillator/Demodulator to the Signal Conditioner Card in the Monitor. Where possible, a single run
of wire from the Oscillator/Demodulator (Junction Box) to the Monitor location should be used.
Splices should be avoided.
The gauge of the selected wire depends on the length of the instrument wire run, and should be as
follows to prevent loss of high frequency signals:
Up to 200 feet 22 AWG
Up to 1000 feet 20 AWG
Up to 4000 feet 18 AWG
The following wiring connection convention should be followed:
Red -24 VDC Power
Black Common
White Signal
Common Point GroundingTo prevent Ground Loops from creating system noise, system common, ground and instrument
wire shield must be connected to ground at one location only. In most cases, the recommendation
is to connect commons, grounds and shields at the Monitor location. This means that all commons,
grounds and shields must be floated (not connected) at the machine.
Occasionally due to installation methods instrument wire shields are connected to ground at the
machine case and not at the monitor. In this case, all of the instrument wire shields must be
floated (not connected) at the monitor.
ConduitDedicated conduit should be provided in all installations for both mechanical and noise protection.
Flexible metal conduit should be used from the Eddy Probe to the Oscillator /Demodulator junction
box, and rigid bonded metal conduit from the junction box to the monitor.
CalibrationAll Eddy Probe systems (Probe, Cable and Oscillator Demodulator) should be calibrated prior to
being installed. This can be done by using a SKF-CM P/N CMSS601 Static Calibrator, -24 VDC Power
Supply and a Digital Volt Meter. The Eddy Probe is installed in the tester with the target set against
the Eddy Probe tip. The spindle micrometer with target attached is then rotated away from the
Eddy Probe in 0.005" or 5 mil increments. The voltage reading is recorded and graphed at each
increment. The SKF-CM CMSS65 and 68 systems will produce a voltage change of 1.0 VDC 0.05
VDC for each 5 mils of gap change while the target is within the NCPU's linear range.
GapWhen installed, Eddy Probes must be gapped properly. In most Eccentricity applications, gapping
the transducer to the center of the linear range is adequate. For the Model 403 transducer gap
should be set for -12.0 VDC using a Digital Volt Meter (DVM), this corresponds to an approximate
mechanical gap of 0.060" or 60 mils. The voltage method of gapping the Eddy Probe is
recommended over mechanical gapping because it is more accurate and easier to accomplish. In
all cases, final Eddy Probe gap voltage should be documented and kept in a safe place.
Eccentricity Installation Checklist
Machine Slow Roll Speed1.
Transducer Orientation Documented2.
Target Material, 4140 Other3.
Smooth Target Area4.
Size of Target Area5.
Junction Box Location(s)6.
Metal Conduit (Junction Box to Monitor)7.
Flexible Conduit (Junction Box to Probe)8.
Correct Instrument Wire9.
Shielding Convention, Monitor or Machine10.
Calibration11.
Gap Set12.
Copyright 2013 STI Vibration Monitoring Inc. All Rights Reserved.
Field Application Note: Eccentricity TSI http://www.stiweb.com/appnotes/Eccentricity-TSI.html
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TURBINE SUPERVISORY INSTRUMENTATION SELECTION GUIDE
MEASUREMENT MODULES RELAY MODULES POWER SUPPLY COMMUNICATIONS SOFTWARE GRAPHIC TERMINALS PROGRAMABLE CONTROLLERS TM
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Introduction
In the past, the primary concern for companies that depend on turbo machinery was simply protecting the asset from catastrophic failure. In today's competitive environment, companies must not only protect their turbo machinery but they must also protect the people that operate it while maximizing production availability by detecting changes early and taking corrective action.
Rockwell Automation - a global leader in industrial automation with more than 100 years of experience serving the changing needs of our customers in industries such as power generation, oil and gas, and others - understands the importance of turbo machinery as a primary mover for critical applications and offers solutions specifically designed to meet the unique requirements of steam, gas, and hydro turbines.
For a solution that includes both protection and monitoring of your critical turbo machinery, Rockwell Automation's proven hardware, software and services include everything you need to be successful.
XM Condition Monitoring and Protection modules
Our XM condition monitoring and protection system gives you the ability to detect changes and faults as early as possible so that uptime and maintenance planning are optimized. In addition to this capability, the modular design and open industry network protocol of XM give you flexibility that results in the most cost effective design, installation and information sharing available.
Emonitor and RSMACC Enterprise Online software
Emonitor and RSMACC Enterprise Online expert data analysis and CMMS integration software makes storage and analysis of data easy, while making it possible to integrate this information into CMMS systems so that the data becomes actionable. Emonitor software also integrates data from portable data collectors and online surveillance systems, giving you a complete picture of plant asset health.
Services
Rockwell Automation is committed to your success. Therefore, you're provided services that include every step - from initial planning and assessment through to the final commissioning and documentation. Rockwell Automation has the ability to perform complete turnkey turbine supervisory instrumentation installation and retrofits or just the support you need to complete your project. All services are designed to meet your specific needs.
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P2 Introduction
TSI System Integration Our integrated solution lowers your total cost by utilizing your existing plant information and control platform as well as open industry standard protocols.
Integrated Architecture
Below is an illustration of a typical Rockwell Automation integrated TSI system.
Ethernet
DeviceNetVersa View
EmonitorEnterprise
PanelView
CMMS RSMACCEnterprise Online
Reliability OnLine
DCS
Proprietary Serial,OPC, Modbus, etc.
Controller
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PTSI System Selection Guide 3
Retrofit Integration
The Rockwell Automation architecture can also be adapted to an existing turbine system. Below is an illustration of a typical Rockwell Automation TSI retrofit system.
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P4 Introduction
Turbine System Comparison
Recommendation is in bold text.
Monitoring System Components Steam Turbine Gas Turbine Hydro TurbineMeasurements Radial Vibration - Shaft
Relative Absolute Shaft
Thrust/Expansion/Position Eccentricity Speed/Accel/Overspeed
Temperature
Phase
Radial Vibration Thrust
Speed
Temperature
Phase
Radial Vibration Thrust
Speed
Temperature
Phase
Measurement Modules XM-120 XM-120E XM-121
XM-121A
XM-160/161/162
XM-220
XM-320 XM-361/362
XM-120
XM-123 XM-160/161/162
XM-220
XM-320
XM-361/362
XM-121 XM-160/161/162
XM-220
XM-320
XM-361/362
Sensors 9000 Series
2100 Series 9000 Series
2100 Series 9000 Series
2100 Series
Power Supply 1606-XLP 1606-XLP 1606-XLP
HMI VersaView PanelView Standard
Strip Chart
LED Indicator
RSView
VersaView PanelView Standard
Strip Chart
LED Indicator
RSView
VersaView PanelView Standard
Strip Chart
LED Indicator
RSView
Control PLC/DCS DeviceNet Interface
ControlLogix
OPC Gateway Gateways and Bridges
Relay Logic (XM-440) 4-20mA I/O
Overspeed Relay (XM-442)
PLC/DCS DeviceNet Interface ControlLogix
OPC Gateway
Gateways and Bridges
Relay Logic (XM-440)
4-20mA I/O
PLC/DCS DeviceNet Interface ControlLogix
OPC Gateway
Gateways and Bridges
Relay Logic (XM-440)
4-20mA I/O
Reliability Emonitor RSMACC EOL ROL
Emonitor
RSMACC EOL
ROL
Emonitor
RSMACC EOL
ROL
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PTSI System Selection Guide 5
System Selection Checklist Use the following Checklist as a guide to specify your turbine system.
Step See 1 Select the measurements
Choose the measurements that you want to monitor on your turbine system.
Steam turbine system Gas turbine system Hydro turbine system
page 7page 19page 25
2 Select modules based on measurement
Match the measurements and the XM modules. Steam turbine systemGas turbine systemHydro turbine system
page 11page 21page 27
3 Select integration strategy
Choose the HMI and control hardware for your system.
HMI productsControl systems
page 31page 33
4 Select software
Choose the software product you need to configure and manage your system.
XM Serial Configuration UtilityRSLinx softwareRSNetworx for DeviceNet softwareEmonitor Enterprise softwareRSMACC EOL software
page 37page 38page 38page 39page 40
5 Select project services
Determine the expertise needed to install a new system, or retrofit an existing one.
Engineering design servicesTurnkey projectsReliability Online Service programsAvailable product servicesTrainingRepair, Exchange & Renewal parts
page 41page 41page 42page 42page 43page 43
6 Select optional accessories
Choose sensors, power supply, enclosure, cables, junction boxes, etc. if necessary.
SensorsPower SuppliesCablesJunction BoxEnclosuresSensor Adhesives / Mounting ToolsPortable Data CollectorsSurveillance Monitoring
page 45page 46page 46page 46page 46page 47page 47page 48
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P6 Introduction
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Steam Turbine System
Measurements This section describes the recommended vibration monitoring for a steam turbine. Use this information to help you select the measurements that you want to monitor.
Radial Vibration Measurement - Shaft Relative
Radial vibration measures the radial motion of the rotating shaft relative to the case. This measurement gives the first indication of a fault, such as unbalance, misalignment, cracked shaft, oil whirl or other dynamic instabilities. Vibration measurements can be made in a single plane or a two plane (X-Y) arrangement where the sensors are 90 degrees apart and perpendicular to the shaft. Eddy current probes are usually installed in a hole drilled through the bearing cap and are held in place by either a bracket or a probe holder.
EXCITERGENERATORLOW PRESSURETURBINEHIGH PRESSURE
TURBINE
VALVE POSITION
SPEED/OVERSPEED
ROTOR ACCELERATION
DIFF. EXPANSION1 SET TO MONITOR
1 SET SPARE
"A""B"
"A""B"
ROTOR/THRUSTPOSITION"A" & "B"
CASEEXPANSIONRIGHT
CASEEXPANSIONLEFT BRG #1 BRG #2 BRG #3 BRG #4 BRG #5 BRG #6 BRG #7
PHASE
ECCENTRICITY
RADIAL MEASUREMENTS
TEMP TEMP TEMP TEMP TEMP TEMP TEMP
(OR OTHER DRIVEN COMPONENT)
Typical Radial System Overview
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P8 Steam Turbine System
Absolute Shaft Measurement
Absolute Shaft Vibration is a measure of the shafts motion relative to free space. The measurement is typically applied when the rotating assembly is five or more times heavier than the case of the machine. Absolute shaft motion is proportional to the vector addition of the casing absolute motion and the shaft relative motion.
Phase Measurement
Phase is defined as the angle between a reference mark (usually a keyway on the shaft) and the heavy spot on the rotor. Phase measurement is required for accurate balancing of any rotor. It also provides an indication of shaft cracks, misalignment, mass loss (such as throwing a blade), and other faults.
Speed/Acceleration Measurement
Speed is a measurement of shaft rotation in revolutions per minute. During start-up, speed is a critical measurement as it allows the operator to: increase speed quickly through shaft critical frequencies; hold the speed stable during heat soak plateaus; and, for electric generators, to accurately match the synchronous frequency before connecting the generator to the power grid.
Acceleration measures how fast speed is increasing or decreasing. It is monitored by the operator during turbine roll up, so that a steady increase in machine speed is achieved. Once the turbine is in normal operation, acceleration is not monitored.
Eccentricity Measurement
Eccentricity is a measurement of the amount of sag or bow in a rotor. It may also provide indication of a bent shaft. This measurement is used by the operator to indicate when the machine can safely be brought up to speed without causing rubs or damage to the seals.
W
D GAPAPPROX..060
PREFERRED(PROTRUSION)
D=1/4W=3/8 OR LARGER
D
W
GAP
(DEPRESSION)ALTERNATE
AXIAL DRILLED HOLE3/8"DIA.x 1/4" DEEP SHIM STOCK
EPOXIED STEEL
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PTSI System Selection Guide 9
Differential Expansion (DE) Measurement
Differential expansion is the difference between the thermal growth of the rotor compared to the thermal growth of the case. Differential expansion monitoring is most critical during a turbine "cold" start-up. A common steam turbine has a thick, heavy case, and a lighter, hollow rotor. Due to the mass of the case it will grow slower than the rotor, so the operator must make sure the case has expanded enough to keep it from making contact with the rotor. To monitor, transducers can be placed on a collar or ramp that have been machined onto the turbine.
Rotor/Thrust Position Measurement
The primary purpose of the thrust position measurement is to monitor thrust bearing wear and to ensure against axial rubs. Dual (redundant) thrust motion detection should be used when the machine is required to shutdown. This method requires two transducers mounted on each bearing. When both independent set points cross the shutdown limit the machine will be turned off. Single thrust motion detection should be used when the machine does not have to be shutdown and there is another means of verifying thrust bearing failure. Thrust position measurements are taken within 12 inches of the thrust bearing, monitoring the thrust collars movement between the active and inactive thrust shoes and their subsequent wear. Measurements taken outside of the thrust bearing area (greater than 12 inches) are generally effected by the rotors thermal expansion and an increase in the required dynamic measurement range. This measurement is typically referred to as rotor (axial) position.
Valve Position Measurement
Valve position is a measurement of how much a valve is open or closed, usually a throttle valve. It provides the operator with an idea of the current load on a machine in the form of a percentage; 0% correlates to a valve closed and 100% correlates to a valve open.
ROTOR LONG
2"MIN.2"MIN. 550mils NOMINAL GAP
Collar
Dual Thrust
Single Thrust
ab
c
d
SHAFT
d = BEVEL ANGLEa = DETECTED RANGEc = INDICATED RANGE
Ramp
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P10 Steam Turbine System
Overspeed - Triple Redundant Protection Measurement
Overspeed is one of the most dangerous conditions that can occur in a turbine, and is defined when a machine accelerates beyond its maximum permissible rotational speed. It is monitored by an Electronic Overspeed Detection System (EODS).
Shell (Case) Expansion Measurement
Steam temperature varies greatly between startup, operation, and shutdown. Shell expansion is a measurement of how much the turbine's case expands from its fixed point outward as it is heated. Continuous indication of shell thermal growth allows the operator to manage the amount of shell distortion as the load is increased or decreased.
Temperature Measurement
Temperature measurements are taken to determine how hot a bearing is operating. These measurements may provide a secondary validation of operation or maintenance problems. An increase in a temperature reading may be due to excessive bearing loading, insufficient clearances, or misalignment.
9-1/23
10-3/16
3-1/44-1/2
15/163/8
2-5/83-1/2
3/4
Figure 9-1
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PTSI System Selection Guide 11
XM Modules The XM series is a group of intelligent, specialty I/O modules designed for machinery protection and condition monitoring. The XM modules monitor critical machinery parameters such as vibration, temperature, position, and speed. The XM modules may be applied as a standalone system, or they can be integrated with existing automation and control systems, including PLCs and displays, to provide maintenance and operations with intelligent information to aid in protecting machinery from catastrophic failures and planning production and maintenance activities.
Your selection of measurements determines which XM module you need for your steam turbine system.
If you want to measure select description
Radial Vibration - Shaft Relative
Phase
XM-120 Standard Dynamic Measurement Module
The XM-120 Standard Dynamic Measurement Module is an intelligent, 2-channel, general-purpose monitor. The module supports monitoring of shaft, casing or pedestal vibration in rotating equipment by accepting input from any eddy current probe, standard accelerometer, or any voltage output measurement device such as a velocity or pressure transducer. In addition to dynamic inputs, the module accepts one tachometer input to provide speed, phase and order analysis functions making it capable of calculating over 14 critical parameters per channel simultaneously.
For more information on the XM-120 module, see publication ENMON-TD120.
Absolute Shaft XM-121 Low Frequency Dynamic Module
The XM-121 Low Frequency Dynamic Module with alternative XM-121A firmware loaded is an intelligent 2-channel monitor capable of supporting a single absolute shaft measurement. The XM-121A firmware is included on the distribution CD with every standard XM-121.
Many of the specifications are similar to the XM-121 Low Frequency Module. The HPFs available in the XM-121 allow for measurements to be as low as .2 Hz (12 CPM).
For more information on the XM-121 module with XM-121A firmware, see publication GMSI10-TD047.
Speed
Acceleration
XM-220 Dual Speed Module The XM-220 Speed Module is an intelligent 2-channel measurement module that accepts input from two tachometers of any standard type including eddy current probes, magnetic pickups, optical tachometers and TTL output devices. The module measures speed, rotor acceleration and peak speed and is capable of detecting zero speed, locked rotor and reverse rotation. The module may also serve as a component of an Electronic Overspeed Detection System (EODS).
For more information on the XM-220 module, see publication ENMON-TD220.
Eccentricity XM-120 Standard Dynamic Measurement Module
The XM-120 Standard Dynamic Measurement Module with alternative XM-120E firmware, enables eccentricity monitoring, critical for steam turbine operation. The XM-120E firmware is included on the distribution CD with every standard XM-120.
For more information on the XM-120 module with XM-120E firmware, see publication ENMON-TD002.
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P12 Steam Turbine System
Differential Expansion
Rotor/Thrust Position
Valve Position
Shell (Case) Expansion
XM-320 Position Module The XM-320 Position Module is a 2-channel multi-purpose monitor. The module can be configured to measure any of: Axial Position, Valve Position, Case Expansion or Differential Expansion. The XM-320 supports multiple single and dual-probe methods of measuring differential expansion. The appropriate method is machine specific and requires review of the installation.
For more information on the XM-320 module, see publication ENMON-TD320.
Temperature XM-361 Universal Temperature Module
or
XM-362 Isolated Temperature Module
The XM-361 Universal Temperature Module is a 6-channel general purpose temperature monitor. Each channel can be configured to measure either an RTD or an isolated thermocouple.
The XM-362 Isolated Temperature Module is a 6-channel temperature monitor designed specifically for use with thermocouples.
For more information on the temperature modules, see publication ENMON-TD361.
Triple Redundant Overspeed
XM-220 Dual Speed Module
XM-442 Voted EODS Relay Module
The XM-442 Voted EODS Relay Module provides high performance voted relays as a component of an Electronic Overspeed Detection System. When coupled with three XM-220 Dual Speed Modules, an XM-442 provides a single 2-out-of-3 overspeed trip relay plus separate relays for alarm (1 of 3 voting), system fault and transducer fault. A single XM-442 paired with three XM-220 modules meets the requirements with regards to the measurement, detection and relay actuation component of API-670 section 5.4.8 Electronic Overspeed Detection.
For more information on the XM-220 module, see publication ENMON-TD220. For more information on the XM-442 module, see publication GMSI10-TD048. For more information on the Electronic Overspeed Detection System, see publication GMSI10-UM015.
If you want to measure select description
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PTSI System Selection Guide 13
Typical Configurations The following configurations are examples of a typical system. Reference OEM specifications and existing sensor dimensions before selecting replacement sensors.
Radial Vibration - Shaft Relative Configuration
For probe holder options, see publication ENACC-PP210.
Absolute Shaft Configuration
TIP Additional requirements may include power supply, enclosure, cables, junction box, sensor adhesives/mounting tools, etc. See Optional Accessories on page 45.
Radial Vibration Configuration Parts
Cat. No. Description Qty
1440-VST02-01RA XM-120 Standard Dynamic Measurement Module 1
1440-TB-A Terminal Base for XM-120 / XM-121 / XM-122 1
Option 1EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 2
EK-2170-0-80 8mm extension cable, 8m 2
EK-2108-9-001 8mm probe driver, 9m system 2
Option 2 (for replacement of existing shaft riders only)
EK-17253 Shaft Rider 18.5 to 20 in 1
EK-09712 Model 544M Velocity Transducer 1
Absolute Shaft Configuration Parts
Cat. No. Description Qty
1440-VLF02-01RA XM-121 Low Frequency Dynamic Measurement Module with XM-121A firmware
1
1440-TB-A Terminal Base for XM-120 / XM-121 / XM-122 1
EK-43808I Model 9100VO Velocity Output Accelerometer 1
EK-46801I 32' Accelerometer Cable (splash proof) 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1
EK-2170-0-80 8mm extension cable, 8m 1
EK-2108-9-001 8mm probe driver, 9m system 1
EK-29000-DPH-01 Dual Probe Holder 1
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P14 Steam Turbine System
Speed/Phase Configuration
Only one option is necessary for a speed/phase measurement.
Speed/Acceleration Configuration
Only one option is necessary for a speed/acceleration measurement.
Phase Configuration Parts
Cat. No. Description Qty
Included with XM-120/121/122/123 Modules
Option 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1
EK-2170-0-80 8mm extension cable, 8m 1
EK-2108-9-001 8mm probe driver, 9m system 1
Option 2
EK-44395 Hall Effect speed sensor, magnetic, zero velocity 1
EK-47774 Cable, Hall Effect speed sensor, 16ft, blunt cut 1
Speed/Acceleration Configuration Parts
Cat. No. Description Qty
1440-SPD02-01RB XM-220 Dual Speed Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
Option 1
EK-2111-40-00-1-10 11mm dia NCPU probe, 1m cable 2
EK-2171-0-80 11mm extension cable, 8m 2
EK-2111-9-001 11mm probe driver, 9m system 2
Option 2
EK-44395 Hall Effect speed sensor, magnetic, zero velocity 1
EK-47774 Cable, Hall Effect speed sensor, 16ft, blunt cut 1
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Eccentricity Configuration
Differential Expansion (DE) Configuration
Eccentricity Configuration Parts
Cat. No. Description Qty
1440-VST02-01RA XM-120 Standard Dynamic Measurement Module with XM-120E firmware
1
1440-TB-A Terminal Base for XM-120 / XM-121 / XM-122 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1
EK-2170-0-80 8mm extension cable, 8m 1
EK-2108-9-001 8mm probe driver, 9m system 1
Differential Expansion Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
EK-48486 Calibrated System, 500 MilIncludes:
(1) 25mm dia tip right angle mounting plate & 1 meter armored cable
(1) 8.0 meter armored extension cable
(1) Drive calibrated for 25mm probe 9 meter electrical length
1
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P16 Steam Turbine System
Rotor/Thrust Position Configuration
Valve Position Configuration
Rotor/Thrust Position Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
Option 1: Rotor/Thrust
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1 or 2
EK-2170-0-80 8mm extension cable, 8m 1 or 2
EK-2108-9-001 8mm probe driver, 9m system 1 or 2
Option 2: Position
EK-2111-40-00-1-10 11mm dia NCPU probe, 1m cable 1
EK-2171-0-80 11mm extension cable, 8m 1
EK-2111-9-001 11mm probe driver, 9m system 1
Valve Position Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
Select one of the following part numbers
EK-15383 LVDT - 0-2 in range 1
EK-15629 Cam (Valve) position detector rotary potentiometer 1400 Ohm
1
EK-16282 Cam (Valve) position detector rotary potentiometer 2000 Ohm
1
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Triple Redundant Overspeed Configuration
Shell (Case) Expansion Configuration
Temperature Configuration
Triple Redundant Overspeed Configuration Parts
Cat. No. Description Qty
1440-SPD02-01RB XM-220 Dual Speed Module 3
1440-TB-B Terminal Base B for XM-320 / XM-220 3
1440-REX03-04RG XM-442 Voted EODS Relay Module 1
1440-TB-G Terminal Base G for XM-442 1
EK-2111-40-00-1-10 11mm dia NCPU probe, 1m cable 3
EK-2171-0-80 11mm extension cable, 8m 3
EK-2111-9-001 11mm probe driver, 9m system 3
Shell (Case) Expansion Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
EK-15383 Linear Variable Displacement Transducers (LVDT) 1
Temperature Configuration Parts
Cat. No. Description Qty
Option 1:Thermocouple or 2 or 3 Wire RTD
1440-TUN06-00RE XM-361 Universal Temperature Module 1
1440-TB-E Terminal Base E for XM-36x 1
Option 2: Isolated Thermocouple
1440-TTC06-00RE XM-362 Isolated TC Temperature Module 1
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Gas Turbine System
Measurements This section describes the recommended vibration monitoring for a gas turbine. Use this information to help you select the measurements that you want to monitor.
Radial Vibration Measurement
Radial Vibration gives the first indication of a fault, such as unbalance, misalignment, cracked shaft, oil whirl, or other dynamic instabilities.
Shaft Relative - Fluid Film (Sleeve/Babbit) Bearing
This measures the radial motion of the rotating shaft relative to the case. Vibration measurements can be made in a single plane or a two plane (X-Y) arrangement where the sensors are 90 degrees apart and perpendicular to the shaft. Eddy current probes are usually installed in a hole drilled through the bearing cap and are held in place by either a bracket or a probe holder.
ShaftShaft TurbineCompressorGENERATOR
(OR OTHER DRIVEN COMPONENT)
BRG #1 BRG #2
TEMP
RADIAL MEASUREMENTS
TEMP
THRUSTPOSITION"A" & "B"
PHASE
SPEED
SPEED
Typical Gas System Overview
IMPORTANT The turbine OEM should be referenced before choosing type and placement of measurements.
Two Plane Arrangement
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P20 Gas Turbine System
Case Absolute - Anti-friction (Ball or Rolling Element) Bearings
Vibration measurements can be made by a transducer mounted on the machines casing. Mounting locations are generally determined by the OEM.
Phase Measurement
Phase is defined as the angle between a reference mark (usually a keyway on the shaft) and the heavy spot on the rotor. Phase measurement is required for accurate balancing of any rotor. It also provides an indication of shaft cracks, misalignment, mass loss (such as throwing a blade), and other faults.
Speed Measurement
Speed is a measurement of shaft rotation in revolutions per minute. Speed is a critical measurement during start-up and operation.
Thrust Position Measurement
The primary purpose of the thrust position measurement is to monitor thrust bearing wear and to ensure against axial rubs. Dual (redundant) thrust motion detection should be used when the machine is required to shutdown. This method requires two transducers mounted on each bearing. When both independent set points cross the shutdown limit the machine will be turned off. Single thrust motion detection should be used when the machine does not have to be shutdown and there is another means of verifying thrust bearing failure.
Temperature Measurement
Temperature measurements are taken to determine how hot a bearing is operating. These measurements may provide a secondary validation of operation or maintenance problems. An increase in a temperature reading may be due to excessive bearing loading, insufficient clearances, or misalignment.
Case MountedArrangement
W
D GAPAPPROX..060
PREFERRED(PROTRUSION)
D=1/4W=3/8 OR LARGER
D
W
GAP
(DEPRESSION)ALTERNATE
AXIAL DRILLED HOLE3/8"DIA.x 1/4" DEEP SHIM STOCK
EPOXIED STEEL
Dual Thrust
Single Thrust
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XM Modules The XM series is a group of intelligent, specialty I/O modules designed for machinery protection and condition monitoring. The XM modules monitor critical machinery parameters such as vibration, temperature, position, and speed. The XM modules may be applied as a standalone system, or they can be integrated with existing automation and control systems, including PLCs and displays, to provide maintenance and operations with intelligent information to aid in protecting machinery from catastrophic failures and planning production and maintenance activities.
Your selection of measurements determines which XM module you need for your gas turbine system.
If you want to measure select description
Radial Vibration
Phase
XM-123 Aeroderivative Module
Note: For FFT, TWF and additional calculated parameters, the XM-120 module (1440-VST02-01RA) should be used in conjunction with the XM-123 module.
The XM-123 Aeroderivative Module is an intelligent 2-channel special-purpose monitor that is uniquely suited for monitoring Aeroderivative Gas Turbines. The XM-123 can be configured, per channel, to perform either tracking filter or band pass style measurements while it also continuously measures each channels broad band overall level. These capabilities, along with its extraordinary configurability, enable the XM-123 to meet the demanding monitoring requirements of almost any engine in service today.
For more information on the XM-123 module, see publication ENMON-TD123. For more information on the XM-120 module, see publication ENMON-TD120.
Speed XM-220 Dual Speed Module The XM-220 Speed Module is an intelligent 2-channel measurement module that accepts input from two tachometers of any standard type including eddy current probes, magnetic pickups, optical tachometers and TTL output devices. The module measures speed, rotor acceleration and peak speed and is capable of detecting zero speed, locked rotor and reverse rotation. The module may also serve as a component of an Electronic Overspeed Detection System (EODS).
For more information on the XM-220 module, see publication ENMON-TD220.
Thrust Position XM-320 Position Module The XM-320 Position Module is a 2-channel multi-purpose monitor. The module can be configured to measure any of: Axial Position, Valve Position, Case Expansion and Differential Expansion.
For more information on the XM-320 module, see publication ENMON-TD320.
Temperature XM-361 Universal Temperature Module
or
XM-362 Isolated Temperature Module
The XM-361 Universal Temperature Module is a 6-channel general purpose temperature monitor. Each channel can be configured to measure either an RTD or an isolated thermocouple.
The XM-362 Isolated Temperature Module is a 6-channel temperature monitor designed specifically for use with thermocouples.
For more information on the temperature modules, see publication ENMON-TD361.
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P22 Gas Turbine System
Typical Configurations The following configurations are examples of a typical system. Reference OEM specifications and existing sensor dimensions before selecting replacement sensors.
Radial Vibration Configuration
Sensors must meet operating temperature requirements. Specialty, high temperature probes and case mounted sensors are available. Special care should be taken when specifying sensor for aeroderivative gas turbine applications.
TIP Additional requirements may include power supply, enclosure, cables, junction box, sensor adhesives/mounting tools, etc. See Optional Accessories on page 45.
Radial Vibration Configuration Parts
Cat. No. DescriptionProbe Operating Temperature Range Qty
1440-VAD02-01RA XM-123 Aeroderivative Module 1
1440-TB-A Terminal Base for XM-123 / XM-120 1
Option 1: Shaft Relative
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable -40 to +350F (-40 to +177C)
2
EK-2170-0-80 8mm extension cable, 8m Connector: max. 257F (+125C)
2
EK-2108-9-001 8mm probe driver, 9m system -36 to +176F (-38 to +80C)
2
Option 2: Case Absolute
EK-43807I 9100HT High Temperature Accelerometer -65 to +500F (-54 to +260C)
1
EK-46801I 32 Accelerometer Cable (splash proof) 1
TIP For FFT, TWF and additional calculated parameters, the XM-120 module (1440-VST02-01RA) should be used in conjunction with the XM-123 module.
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Phase/Speed Configuration
Only one option is necessary for a phase/speed measurement.
Thrust Position Configuration
Phase Configuration Parts
Cat. No. Description Qty
Phase/Speed
Included with XM-123/120/121/122 Modules
Speed
1440-SPD02-01RB XM-220 Dual Speed Module 1
1440-TB-B Terminal Base B for XM-220 / XM-320 1
Option 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1
EK-2170-0-80 8mm extension cable, 8m 1
EK-2108-9-001 8mm probe driver, 9m system 1
Option 2
EK-44395 Hall Effect speed sensor, magnetic, zero velocity 1
EK-47774 Cable, Hall Effect speed sensor, 16ft, blunt cut 1
Thrust Position Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Dual Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1 or 2
EK-2170-0-80 8mm extension cable, 8m 1 or 2
EK-2108-9-001 8mm probe driver, 9m system 1 or 2
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P24 Gas Turbine System
Temperature Configuration
Temperature Configuration Parts
Cat. No. Description Qty
Option 1: Thermocouple or 2 or 3 Wire RTD
1440-TUN06-00RE XM-361 Universal Temperature Module 1
1440-TB-E Terminal Base E for XM-36x 1
Option 2: Isolated Thermocouple
1440-TTC06-00RE XM-362 Isolated TC Temperature Module 1
1440-TB-E Terminal Base E for XM-36x 1
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Hydro Turbine System
Measurements This section describes the recommended vibration monitoring for a hydro turbine. Use this information to help you select the measurements that you want to monitor.
Radial Vibration Measurement
Radial Vibration gives the first indication of a fault, such as unbalance, misalignment, cracked shaft, oil whirl, or other dynamic instabilities.
Shaft Relative - Fluid Film (Sleeve/Babbit) Bearing
This measures the radial motion of the rotating shaft relative to the case. Vibration measurements can be made in a single plane or a two plane (X-Y) arrangement where the sensors are 90 degrees apart and perpendicular to the shaft. Eddy current probes are usually installed in a hole drilled through the bearing cap and are held in place by either a bracket or a probe holder.
Shaft
Turbine
SPEED/PHASE
TEMP
TEMPTHRUSTPOSITION"A" & "B"
Generator
CAVITATION
RADIAL
MEASUREMENTS
Typical Hydro Turbine System Overview
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P26 Hydro Turbine System
Case Absolute - Anti-friction (Ball or Rolling Element) Bearings
Vibration measurements can be made by a transducer mounted on the machines casing. Mounting locations are generally determined by the OEM.
Cavitation is defined as the formation of vapor pockets in a liquid. In hydro turbines, cavitation can cause a large amount of noise, damage to the machine, and a loss of efficiency. It is measured by a case mounted accelerometer on either the draft tube or turbine head cover.
Phase/Speed Measurement
Phase is defined as the angle between a reference mark (usually a keyway on the shaft) and the heavy spot on the rotor. Phase measurement is required for accurate balancing of any rotor. It also provides an indication of shaft cracks, misalignment, mass loss (such as throwing a blade), and other faults.
Speed is a measurement of shaft rotation in revolutions per minute. Speed is a critical measurement during start-up and operation.
Thrust Position Measurement
The primary purpose of the thrust position measurement is to monitor thrust bearing wear and to ensure against axial rubs. Dual (redundant) thrust motion detection should be used when the machine is required to shutdown. This method requires two transducers mounted on each bearing. When both independent set points cross the shutdown limit the machine will be turned off. Single thrust motion detection should be used when the machine does not have to be shutdown and there is another means of verifying thrust bearing failure.
Temperature Measurement
Temperature measurements are taken to determine how hot a bearing is operating. These measurements may provide a secondary validation of operation or maintenance problems. An increase in a temperature reading may be due to excessive bearing loading, insufficient clearances, or misalignment.
Cavitation
W
D GAPAPPROX..060
PREFERRED(PROTRUSION)
D=1/4W=3/8 OR LARGER
D
W
GAP
(DEPRESSION)ALTERNATE
AXIAL DRILLED HOLE3/8"DIA.x 1/4" DEEP SHIM STOCK
EPOXIED STEEL
Dual Thrust
Single Thrust
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XM Modules The XM series is a group of intelligent, specialty I/O modules designed for machinery protection and condition monitoring. The XM modules monitor critical machinery parameters such as vibration, temperature, position, and speed. The XM modules may be applied as a standalone system, or they can be integrated with existing automation and control systems, including PLCs and displays, to provide maintenance and operations with intelligent information to aid in protecting machinery from catastrophic failures and planning production and maintenance activities.
Your selection of measurements determines which XM module you need for your hydro turbine system.
If you want to measure select description
Radial Vibration
Phase
XM-121 Low Frequency Dynamic Module
The XM-121 Low Frequency Vibration Module is identical to the XM-120 Standard Vibration Module except for the available high pass filter (HPF) selections. The HPFs available in the XM-121 allow for measurements to be as low as .2 Hz (12 CPM) making it ideal for monitoring low speed machinery such as hydroturbines and many fans, gearboxes, paper rolls, extruder presses and other low speed equipment.
For more information on the XM-121 module, see publication ENMON-TD120.
Speed XM-220 Dual Speed Module The XM-220 Speed Module is an intelligent 2-channel measurement module that accepts input from two tachometers of any standard type including eddy current probes, magnetic pickups, optical tachometers and TTL output devices. The module measures speed, rotor acceleration and peak speed and is capable of detecting zero speed, locked rotor and reverse rotation. The module may also serve as a component of an Electronic Overspeed Detection System (EODS).
For more information on the XM-220 module, see publication ENMON-TD220.
Thrust Position XM-320 Position Module The XM-320 Position Module is a 2-channel multi-purpose monitor. The module can be configured to measure any of: Axial Position, Valve Position, Case Expansion and Differential Expansion.
For more information on the XM-320 module, see publication ENMON-TD320.
Temperature XM-361 Universal Temperature Module
or
XM-362 Isolated Temperature Module
The XM-361 Universal Temperature Module is a 6-channel general purpose temperature monitor. Each channel can be configured to measure either an RTD or an isolated thermocouple.
The XM-362 Isolated Temperature Module is a 6-channel temperature monitor designed specifically for use with thermocouples.
For more information on the temperature modules, see publication ENMON-TD361.
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P28 Hydro Turbine System
Typical Configurations The following configurations are examples of a typical system. Reference OEM specifications and existing sensor dimensions before selecting replacement sensors.
Radial Vibration Configuration
TIP Additional requirements may include power supply, enclosure, cables, junction box, sensor adhesives/mounting tools, etc. See Optional Accessories on page 45.
Radial Vibration Configuration Parts
Cat. No. Description Qty
1440-VLF02-01RA XM-121 Low Frequency Dynamic Measurement Module 1
1440-TB-A Terminal Base A for XM-120 / XM-121 / XM-122 1
Option 1: Shaft Relative
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 2
EK-2170-0-80 8mm extension cable, 8m 2
EK-2108-9-001 8mm probe driver, 9m system 2
Option 2: Case Absolute and Cavitation
EK-43784I 9100 General Purpose Accelerometer 1
EK-46801I 32 Accelerometer Cable (splash proof) 1
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Phase/Speed Configuration
Only one option is necessary for a phase/speed measurement.
Thrust Position Configuration
Phase/Speed Configuration Parts
Cat. No. Description Qty
Phase/Speed
Included with XM-121/120 Modules
Speed
1440-SPD02-01RB XM-220 Dual Speed Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
Option 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1
EK-2170-0-80 8mm extension cable, 8m 1
EK-2108-9-001 8mm probe driver, 9m system 1
Option 2
EK-44395 Hall Effect speed sensor, magnetic, zero velocity 1
EK-47774 Cable, Hall Effect speed sensor, 16ft, blunt cut 1
Thrust Position Configuration Parts
Cat. No. Description Qty
1440-TPS02-01RB XM-320 Position Module 1
1440-TB-B Terminal Base B for XM-320 / XM-220 1
EK-2105-70-00-1-10 8mm dia NCPU probe, 1m cable 1 or 2
EK-2170-0-80 8mm extension cable, 8m 1 or 2
EK-2108-9-001 8mm probe driver, 9m system 1 or 2
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Temperature Configuration
Temperature Configuration Parts
Cat. No. Description Qty
Option 1: Thermocouple or 2 or 3 Wire RTD
1440-TUN06-00RE XM-361 Universal Temperature Module 1
1440-TB-E Terminal Base E for XM-36x 1
Option 2: Isolated Thermocouple
1440-TTC06-00RE XM-362 Isolated TC Temperature Module 1
1440-TB-E Terminal Base E for XM-36x 1
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Integration Products
This section describes the integration strategy. Select the human machine interface (HMI), control system, and reliability products that best fit your needs.
XM systems use the DeviceNet open standard for all communications. DeviceNet is an open, low-level network that provides connections between simple industrial devices (such as sensors and actuators) and higher-level devices (such as HMIs, PLCs, and computers). The DeviceNet network uses the proven Common Industrial Protocol (CIP) to provide the control, configure, and data collection capabilities for industrial devices.
HMI Products Rockwell Automation offers the following HMI products for your system.
VersaView Industrial Computers and Monitors
VersaView products are a family of industrial computer and monitor solutions, comprised of integrated display computers, workstations, non-display computers, and flat panel monitors. VersaView products offer effortless management of changing technology, a rugged but cost-effective design, and easier product configuration. All VersaView products provide the latest industrial solution available, optimized for visualization, control, information processing, and maintenance application.
VersaView CE Industrial Computers
VersaView CE products offer open Windows CE terminals in Windows desktop environments - bringing together features of operator interfaces and industrial computers. It is a high performance computer with a compact flash drive and integrated RSView Machine Edition runtime (no activation required). Theres no hard disk, no fan, and no moving parts, which means maximum reliability on the plant floor. Easy to set up and maintain, VersaView CE means an open system thats rugged and economical, offering high functionality in an easy to use package.
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RSView Enterprise Series Software
RSView Enterprise Series software from Rockwell Software is a line of HMI software products designed with a common look, feel, and navigation to help speed HMI application development and training time. With RSView Enterprise Series 3.0, you can reference existing Logix data tags. Any changes made to these referenced tags are automatically inherited by RSView software. RSView Enterprise Series software includes:
RSView Studio lets you create applications in a single design environment. It configures RSView Supervisory Edition, RSView Machine Edition, VersaView CE, and PanelView Plus applications. It supports editing and reusing projects for improved portability between embedded machine and supervisory HMI systems.
RSView Machine Edition (ME) is a machine-level HMI product that supports both open and dedicated operator interface solutions. It provides a consistent operator interface across multiple platforms (including Microsoft Windows CE, Windows 2000/XP, and PanelView Plus solutions), and is ideal for monitoring and controlling individual machines or small processes.
RSView Supervisory Edition (SE) is an HMI software for supervisory-level monitoring and control applications. It has a distributed and scalable architecture that supports distributed-server/multi-user applications. This highly scalable architecture can be applied to a stand-alone, one-server/one-user application or to multiple users interfacing with multiple servers.
PanelView Standard Operator Terminals
PanelView Standard operator terminals are engineered for maximum performance in space saving flat panel designs. These electronic operator interfaces feature pixel graphics capabilities and high-performance functionality in color, grayscale, and monochrome displays. The PanelView Standard family offers a complete line of rugged electronic operator interface solutions in a variety of sizes and configurations to meet specific application requirements, all with a rich collection of hardware and software features designed to simplify programming and improve operator productivity. The high performance functionality of the PanelView Standard line includes advanced alarm handling, screen security, analog gauges, ATA PC memory card, universal language support, and online printing for more intuitive operator control.
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PTSI System Selection Guide 33
Control Systems Rockwell Automation offers the following control system solutions for your system.
PLC/DCS DeviceNet Interface
The XM module may be linked directly to a PLC or other control system via industry standard DeviceNet scanner cards. Host controllers can then scan XM modules for data, alarm and relay status information in real-time. Prioritizing messaging insures that changes to any alarm or relay status is immediately communicated to network controllers.
ControlLogix
The ControlLogix system provides sequential, process, motion, and drive control together with communications and state-of-the-art I/O in a small, cost-competitive package. The system is modular, so you can design, build, and modify it efficiently - with significant savings in training and engineering. A simple ControlLogix system consists of a standalone controller and I/O modules in a single chassis.
You can also use the ControlLogix system as a gateway. Include the communication modules you need for connectivity to other networks. For this use, a controller is not required. The ControlLogix Gateway integrates into existing PLC-based systems so that users with existing networks can send or receive messages to or from other networks.
For more information on the ControlLogix products, see publication 1759-SG001.
OPC Gateway
OPC (OLE for Process Control) is a set of industry-standard specifications that allow plant floor devices such as DCSs and PLCs to communicate and exchange data with software applications such as HMIs and Process Historians. The OPC standards allow different automation and control applications, field systems and devices, and business and office applications supplied by different vendors to work with one another.
RSLinx Classic software is an OPC-compliant server exposing the required interfaces for an OPC client application to access data consistent with other OPC-compliant servers.
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Gateways and Bridges
XM-500 Ethernet Gateway
The XM-500 Ethernet Gateway provides a powerful bridge between an XM DeviceNet network and Ethernet. The Gateway provides complete DeviceNet Master functionality and support for a fully populated DeviceNet network with up to 63 devices. On the Ethernet side, the XM-500 offers a standard TCP/IP interface and support for the Ethernet protocol. Recommended for systems designed primarily to communicate with RSMACC EOL and Emonitor.
For more information, see publication ENMON-TD500.
1788 EN2DN Ethernet/IP to DeviceNet Linking Device
The 1788 EN2DN Ethernet/IP to DeviceNet Linking Device has the capability to bridge explicit messages from an Ethernet/IP network to a DeviceNet network, or scan the DeviceNet network via Ethernet/IP. Can be used with any Logix controller or third party controller with Ethernet/IP support. Recommended for systems requiring integration with automation environments, e.g. PLCs, and visualizations.
1788 CN2DN ControlNet to DeviceNet Linking Device
One side of the Linking Device is a DeviceNet scanner with the capacity for handling 500 bytes of data in and out from DeviceNet compliant devices. The other side is a ControlNet scheduled adapter with redundant media communications and a Network Access Port.
XM-440 Master Relay Module
The XM-440 Master Relay Module combines four relay outputs with XM bus master capabilities to provide remote, shared and voted relay operation for distributed XM measurement modules. The XM-440 module offers high power relays suitable for use in most protection applications.
IMPORTANT Rockwell Automation's Encompass Partners provide additional gateways for almost any network; see http://www.rockwellautomation.com/encompass/ for further details.
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XM-442 Voted EODS Relay Module
The XM-442 module is designed to mate with three XM-220 Dual Speed Modules to provide an API compliant triple redundant Electronic Overspeed Detection System (EODS). The XM-442 provides four high power relays that serve as the EODS alarm and shutdown relays.
4-20mA Outputs
The XM modules offer a 4-20mA isolated analog output per channel proportional to the selected measurement. Each output is independently programmed to represent any measured parameter, from either channel with a maximum load of 300 ohms. The 4-20mA outputs can interface directly with existing strip chart recorders and LED indicators to monitor and control the health of your turbine system.
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Software Products
Your network configuration determines what software packages you need to configure and manage your system.
XM Serial Configuration Utility Software
The XM Serial Configuration Utility software is an easy to use Windows application for installing and configuring the XM Series modules. The tool can read, write, and modify configurations stored on disk, upload configuration from a module; download configurations and firmware updates to a module; and view data from a module.
The Utility software is provided on the XM Documentation and Configuration Utility CD that is packaged with the XM modules.
IMPORTANT To use the XM Serial Configuration Utility, connect the PC to a modules serial port using the following serial cable.
Cat. No. Description
1440-SCDB9-FXM2 XM Serial Communications Cable
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P38 Software Products
RSLinx Software RSLinx software is a complete communication server providing plant-floor device connectivity for a wide variety of Rockwell Software applications such as RSLogix 5/500/5000, RSView32, RSView Enterprise Series, and RSMACC Enterprise Online Condition Monitor (RSMACC EOL). In addition, several open interfaces are provided for third-party HMI, data collection and analysis packages, and custom client-application software. RSLinx software can support multiple software applications simultaneously, communicating to a variety of devices on many different networks.
RSLinx 2.x software is now joined by RSLinx Enterprise software, a new product within the RSLinx family that provide unparalleled connectivity to Logix processors. RSLinx Enterprise software currently can support working as a data server for widely distributed RSView Supervisory Edition products, RSSql, RSBizWare Historian, and RSBizWare PlantMetrics applications, RSView Machine Edition including PanelView Plus and VersaView hardware platforms, and RSView Supervisory Edition Station.
You can communicate from anywhere to anywhere using RSLinx software. RSLinx v2.43 or later is required for compatibility with the entire line of XM modules.
RSNetWorx for DeviceNet Software
RSNetWorx software configures and manages the communication between the devices on your control network. RSNetWorx for DeviceNet provides an instant, selectable view of any DeviceNet network. With this software, you can
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PTSI System Selection Guide 39
configure DeviceNet I/O devices and create a scan list. The DeviceNet scanner stores the configuration information and scan list.
Emonitor Enterprise Software
The Emonitor suite is a complete machinery information software system for Condition Based Maintenance programs. By incorporating multiple data sources, such as online systems, portable data collectors and OPC servers, Emonitor can easily present a complete picture of the state of your machinery. A collection of analysis tools, statistical based alarms and rule-based logic allows you to quickly and easily identify problem areas among large amounts of data.
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P40 Software Products
Emonitor historical data can be accessed via any application utilizing the following data access standards:
Open Database Connectivity (ODBC) - ODBC provides access to data from any application regardless of which database management system (DBMS) is handling the data. It is independent of programming language, database system, and operating system.
MIMOSA - MIMOSA is an open standard in which equipment asset software components are able to communicate and exchange data automatically without propriety or supplier-specific interface protocols.
Extensible Markup Language (XML) - XML is a simple, flexible text format designed to facilitate the sharing of data across different systems. Programs are able to modify and validate documents in languages based on XML without prior knowledge of their form.
RSMACC Enterprise Online Software
RSMACC Enterprise Online Condition Monitor is an information presentation and analysis tool that provides you the ability to quickly and intuitively evaluate plant, machinery, and system status at a glance. Using the Enterprise Online Configuration Utility from within RSMACC Enterprise Online Condition Monitor, you can remotely configure data collection parameters, alarms, and relays on the XM modules.
Third Party Software Rockwell Automation offers connectivity solutions allowing our products to
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Project Services
A TSI system retrofit begins with a walk down of the machine and the creation of a project scope document. From this, a bill of material and quotation document will be generated.
Rockwell Automation Project Services provides the expertise needed to scope and install a new TSI system, or the retrofit of an existing one.
Engineering Design Services
Rockwell Automation has the engineering resources and specific TSI knowledge to effectively design a new system or plan a retrofit. The design services include:
Functional Design Specification Installation Drawings Custom Product Design Application Review Network Evaluation Customized Operational and Troubleshooting Guides
Turn Key Rockwell Automations performance history and depth of knowledge help to deliver successful turnkey projects.
Project Management Plan, design, build and install the solution Integrate TSI solution with other plant systems Factory Acceptance Testing with Documentation Package suitable for
most ISO 9000 Requirements Mechanical and Electrical services On-Site Acceptance Testing with Documentation Package System Commissioning Software Configuration As-Built Drawing Package Factory or On-Site Training of plant personnel on operation and
maintenance of the system Final Report Documentation Package
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P42 Project Services
Reliability Online (ROL) Service Programs
Rockwell Automation ROL Services turns TSI data into actionable Condition-based Maintenance information.
The TSI system can be designed to be accessed over a phone line or through a secure internet connection
Regular or on demand analysis expertise is provided remotely Asset health information is accessed through the internet with an easy
to use web portal (see illustration below)
Select the Product ServicesServices Menu
Cat. No. Description
1443-S-OLTK Turnkey Installations and Services for on-line systems
1443-S-DOC Documentation Service - Reports, Drawings and System Specifications
1443-S-MON On-line Systems Commissioning, Inspection, Application and Training
1443-S-CAL Standard Annual Calibration or Troubleshooting Service for on-line systems
1443-ROL-CAS Reliability Online (ROL) analysis service
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Training Utilizing the Rockwell Automation training offerings can significantly improve the productivity and efficiency of the plant floor staff by giving them the knowledge, skills and learning aids to maintain both legacy automation systems and todays advanced automation technologies.
Repair, Exchange & Renewal Parts
Rockwell Automation provides comprehensive repair services including remanufacturing services for a wide variety Rockwell Automation products, repair services for non-Rockwell Automation products, exchange services for over 12,000 Allen-Bradley catalog products, and renewal parts for many legacy Allen-Bradley products.
Training Menu
Course No. Description
CCP422 DeviceNet Maintenance and Troubleshooting
CCP163 DeviceNet/RSNetWorx Design and Configuration
EK-ICM101 Introduction to Vibration Technology
EK-ICM121 Dynamic Balancing
EK-ICM141 Emonitor Odyssey/Enshare Basic
EK-ICM162 Using Your Enpac with Emonitor
EK-ICM165 XM System Fundamentals
EK-ICM201 Vibration Analysis I
EK-ICM221 Emonitor Odyssey/Enshare Advanced
EK-ICM261 Vibration Analysis II
EK-ICM281 Time Waveform Analysis
EK-ICM301 Vibration Analysis III
RS-RSMACC RSMACC Installation and Configuration
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Optional Accessories
Sensors Rockwell Automation offers a comprehensive range of Sensors for use with both condition monitoring and protection systems.
Accelerometers bare the workload in vibration monitoring and data collection processing. Designed for use in a broad range of applications, various types of accelerometers including high frequency, low frequency, high temperature, and specialty sensors offer a variety of frequency ranges and reference sensitivities to provide the best selection for each measurement concern.
9000 Series Accelerometers
9000 series Accelerometers are designed for use in a broad range of applications including high frequency, low frequency and high temperature and offer a variety of frequency ranges and reference sensitivities to provide the best selection for each measurement application.
For more information on 9000 series accelerometers, see publication GMSI10-SG001, which is available on the Rockwell Automation web site (http://www.rockwellautomation.com/services/conditionmonitoring/sensors.html).
2100 Series
The 2100 Series of non-contact pick-ups are designed to meet the stringent requirements of the American Petroleum Institute (API) Standard 670. The sensors are non-contacting eddy-current type transducers that measure the dynamic and/or static displacement of the target relative to the mounting fixture. The system consists of a non-contact pickup probe, oscillator/demodulator (probe driver) and interconnecting cable. These systems are typically used to measure shaft radial and axial vibration, shaft eccentricity, shaft axial position, case expansion, differential expansion and other instances where non-contacting, relative measurements must be made.
We also provide a variety of probe holder options. For more information on 2100 series non-contact pickups and probe holder options, see publication ENACC-PP210, which is available of the Rockwell Automation web site (http://www.rockwellautomation.com/services/conditionmonitoring/sensors.html).
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P46 Optional Accessories
Power Supplies The XM series is designed to operate with 24V DC power supplies. The following Allen-Bradley 1606-XLP power supplies are recommended for use with all XM applications. The 1606-XLP series is a general purpose, DIN-rail-mount power supply.
Capacity of the power supply must meet or exceed the total maximum load required by the XM system. If the total system power requirement exceeds the 1606-XLP-100E power supply, use multiple powers supplies and connections. Note that the total current draw through the side connector cannot exceed 3A. Maximum loads for each module can be found in the data sheet and User Manual for the specific module.
It may be necessary to provide a redundant power source to the XM system for critical applications. All XM modules provide redundant power supply input terminals so if the primary 24V power supply fails, the secondary power supply will automatically be used in its place.
For assistance in calculating the power requirements for your XM system, contact your local Rockwell Automation Customer Service.
Cables Rockwell Automation offers a variety of cables for interfacing industrial vibration sensors to termination and switch boxes, portable data collectors, readout devices, and recording and analysis instruments. For individual product offerings, see publication GSMG10-PL001.
Junction Box Rockwell Automation offers a 20 terminal junction box to house electrical components and facilitate wiring. For individual product offerings, see publication GMSG10-PL001.
Enclosures Rockwell Automation offers a broad line of UL approved NEMA enclosures to house and protect your XM system. NEMA enclosures are rated by the National Electrical Manufacturers Association (NEMA) and designed for hazardous or non-hazardous locations and indoor or outdoor use.
Cat. No. Full Rated Load
1606-XLP-30E 1.3A
1606-XLP-50E 2.1A
1606-XLP-100E 4.2A
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PTSI System Selection Guide 47
Rockwell Automation offers the following enclosure types.
NEMA Type 4X and 12 rated enclosures are available with solid door or polycarbonate window.
For individual product offerings, see publication GMSG10-PL001.
Sensor Adhesives / Mounting Tools
Rockwell Automation offers sensor adhesives and mounting tools to prepare the machinery surfaces for installation of the sensors. For individual product offerings, see publication GMSG10-PL001.
Portable Data Collectors A portable data collector is capable of performing condition monitoring data collection, analysis, and root cause correction. The Enpac portable data collectors are Windows CE based, high performance, data collectors and signal analyzers. Their comprehensive measurement capability, analysis functions and ease of use make them the perfect tool for a portable predictive maintenance strategy.
The Enpac 2500 is an easy to use, cost effective, scalable solution that meets the needs of the novice as well as advanced user. Key attributes include size, easy to read color display, and speed of data collection. The Enpac 2500 is a rugged and reliable instrument with a built in laser tachometer and advanced analysis capabilities such as optional 2-channel functions, 2-plane balancing, and more.
For more information on the Enpac 2500, see publication GMSI10-PP03.
Enclosure Type Intended Use and Description
NEMA 4 Indoor or outdoor use primarily to provide a degree of protection against windblown dust and rain, splashing water, and hose directed water; undamaged by the formation of ice on the enclosure.
NEMA 4X Indoor or outdoor use primarily to provide a degree of protection against corrosion, windblown dust and rain, splashing water, and hose-directed water; undamaged by the formation of ice on the enclosure.
NEMA 12 Indoor use primarily to provide a degree of protection against dust, falling dirt, and dripping noncorrosive liquids.
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P48 Optional Accessories
Surveillance Monitoring The Enwatch is a cost-effective solution for monitoring the condition of the important machines in a plant. It bridges the gap between portable data collectors with manual periodic update capabilities and more expensive continuous monitoring systems.
For more information on the Enwatch, see publication GMSI10-PP014.
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GMSI10-SG002A-EN-P - June 2006 Copyright 2006 Rockwell Automation, Inc. All Rights Reserved. Printed in USA.
Listen. Think. Solve, Allen-Bradley, Emonitor, PanelView, RSBizware Historian, RSBizware PlantMetrics, RSLinx, RSLogix, RSMACC, RSSQL, VersaView and XM are trademarks ofRockwell Automation, Inc.
DeviceNet is a trademark of the Open DeviceNet Vendor Association (ODVA).
Windows is a registered trademarks of the Microsoft Corporation.
Trademarks not belonging to Rockwell Automation are property of their respective companies.
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TURBINESUPERVISORY
GUIDE
25YEARS1978 -2003
TECHNIQUES FOR THEMONITORING & PROTECTION OF
POWER PLANT EQUIPMENT
TURBINESUPERVISORY
GUIDE
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Introduction
OverviewTSE Application Diagram
Transducers and SensorsAccelerometerVelocity TransducerEddy Current Proximity ProbeLVDT/RVDTChoosing the right transducer
Measurement TechniquesAbsolute VibrationEccentricity & Shaft VibrationRotor Differential ExpansionShaft PositionSpeed MonitoringCasing & Cylinder Expansion Valve Position Monitoring
Auxiliary Plant Monitoring
Protection SystemsIntroduction to API Standard 670
Special TechniquesRod Drop Rundown MonitoringOrbit Analysis
System EquipmentBracketryCubicle Panels
Seismic Monitoring andProtection Equipment
Site References
Quick Product Selection Guide
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3INTRODUCTION
For nearly 30 years Sensonics has been supplyingTurbine Condition Monitoring solutions to thepower generation industry worldwide. Involved inmeasurement definition through to supply andfinal system commissioning, our experience withinthe power sector is second to none.
We have produced this guide to capture theessence of that experience and to explain thebasics of vibration and expansion measurementtechniques relating to turbine and auxiliary plantequipment.
The guide starts with an introduction to the basictransducers available for plant mounting withassociated options, and details the variousmeasurement techniques used as standardthroughout the power industry. This is followed bytypical equipment protection configurations forsafe plant shutdown. In the final part of this guidethe system components are introduced andspecial measurement regimes discussed.
The guide aims to provide a balance of basictheory and practical advice but obviously cannotcover all measurement scenarios. For a detaileddiscussion on any measurement issues you mayhave, please feel free to contact Sensonics.
SENSONICSPRODUCTS & COMPETENCES
Turbine Supervisory Systems
Standalone Monitoring Solutions
Accelerometer, Displacement &
Seismic Transducers
Nuclear Infrastructure Protection
Structural Monitoring Solutions
Turn-Key Design, Manufacture and
Project Support
ATEX & IEC61508 Capability
Installation & Commissioning
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4OVERVIEWTurbine supervision is an essential part of the day-to-dayrunning of any power plant. There are many potentialfaults such as cracked rotors and damaged shafts, whichresult from vibration and expansion.When this expansionand vibration is apparent in its early stages the problemcan usually be resolved without any of the disruptioncaused when a turbine has to be shut down. Byappropriate trending of the various measurement pointsand the identification of excessive vibration ormovement, scheduled equipment stoppages or outagescan often be utilised to investigate and resolve the failuremechanism.
It is for this predictive maintenance market that Sensonicsproduces a wide range of sensors and systems specificallyfor the power generation industry. With flexible andconfigurable equipment, we can tailor our supervisoryequipment to your needs. In this brochure we aim togive a brief explanation of why turbine supervision is soessential and how Sensonics can provide the rightsolution to protect your turbine.
The diagram on page 5 illustrates a generic configurationof a set of Turbine Supervisory equipment. The steamturbine shown is fairly standard with an HP (highpressure) stage followed by a single LP (low pressure)rotor section; different turbine configurations dependingon power rating, may have an intermediate (IP) section inaddition to a number of LPs which finally drive theturbine generator.This type of configuration is illustratedin the adjacent picture. Although the equipmentconfiguration does vary, the measurement techniquesremain the same, with each turbine installation generatingits own unique set of measurements. Typicalmeasurement techniques include:-
Absolute vibration of bearing pedestalsShaft vibration relative to bearingShaft eccentricityDifferential expansion or shaft movementValve position on steam inletCasing expansion, both inner and outerSpeed, including overspeed and zero speedTemperatureStructural & foundation vibration monitoring
Each of the measurement techniques are used to monitorthe turbine during its operating cycle, somemeasurements may be configured to provide warningalarms as well as automated shutdown, although thesesystems tend to operate on a voted principle to ensuremaximum system integrity.
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6Shear mode devices which apply a shear force to theinner and outer surfaces of a ring of crystal (as opposedto a perpendicular force to a disk of crystal), offer adistinct advantage over standard compression techniques.When mounting the device to the plant, normally througha stud & screw arrangement, the mechanical stresseswithin the transducer assembly change. Compressionmode devices are particularly affected by these stresses,which produce low frequency effects, compounded iffurther integration is carried out. Sensonics shear moderange of transducers are unaffected by base strain andoffer a true low frequency performance down to 0.4Hz.
Although the piezoelectric accelerometer is a self-generating device, its output is at a very high impedanceand is therefore unsuited for direct use with most display,analysis, or monitoring equipment.Thus, electronics mustbe utilised to convert the high impedance crystal outputto a low impedance capable of driving such devices. Theimpedance conversion electronics may be located withinthe accelerometer, outside of but near the accelerometer,or in the monitoring or analysis device itself.
Accelerometers with internal electronics are convenientand can use inexpensive conventional plugs and cable butthey are limited to temperatures of typically 120C.Locating the electronics in a cool location away from theaccelerometer allows the transducer to tolerate highertemperatures.
TRANSDUCERS & SENSORS
The Accelerometer
The accelerometer is based on the electrical propertiesof piezoelectric crystal. In operation, the crystal isstressed by the inertia of a mass. The variable forceexerted by the mass on the crystal produces an electricaloutput proportional to acceleration. Two commonmethods of constructing the device to generate a residualforce are compression mode and shear moderespectively. A residual force is of course required toenable the crystal to generate the appropriate response,moving in either direction on a single axis. A shear modeconstruction is illustrated below. An accelerometer operates below its first natural
frequency. The rapid rise in sensitivity approachingresonance is characteristic of an accelerometer, which isan un-damped single-degree-of-freedom spring masssystem. Generally speaking, the sensitivity of anaccelerometer and the ratio between its electrical outputand the input acceleration is acceptably constant toapproximately 1/5 to 1/3 of its natural frequency. For thisreason, natural frequencies above 30KHz tend to be used.
The frequency response curve can be influenced by anumber of factors, mainly the mass, the stiffness and thedegree of system damping. The resonant peak of theaccelerometer can be eliminated by increasing thedamping. However, increasing the damping introduces aphase shift in the linear range whereas un-dampedaccelerometers have very little phase shift until near thenatural frequency. It is therefore usual to have un-dampedaccelerometers with very high natural frequencies so thatthe linear range is extended as far as possible. Typicaldamping ratios are 0.01 to 0.05.
This resonant frequency in combination with theappropriate damping can be utilised to monitor bearingimpact. Several manufacturers, including Sensonics havedeveloped transducers that utilise the ringing of thetransducer to mechanical impulses to measure the healthof roller bearings. This technique analyses the highfrequency response of the transdu