tab005 - 3w_ac_mit_control system.pdf

1

Control SystemControl System

2

Learning objective

At the completion of this lesson, the student will be able to:

• locate and Identify the control panel components• Understand the function of main logic and inverter controller. • Explain the purpose of using CAN-bus• Understand how to discharge an inverter controller.• Understand what is a MOS-FET

All Registered trademarks herein are the property of their respeAll Registered trademarks herein are the property of their respective owners.ctive owners.The information set forth herein is confidential and is not for The information set forth herein is confidential and is not for distribution beyond MCFS and its distribution beyond MCFS and its authorisedauthorised Mitsubishi Forklift Trucks andMitsubishi Forklift Trucks andMIT MIT ®® Forklift Trucks dealer network.Forklift Trucks dealer network.Copyright Copyright ©© by MCFS. All rights reserved. Reproduction of this material in by MCFS. All rights reserved. Reproduction of this material in any form is Prohibited without written permission of MCFS.any form is Prohibited without written permission of MCFS.

3

System Layout

MC Block DiagramMC Block Diagram

CAN-bus electrical system• The data transmission is handled via a CAN-bus system.• CAN-bus ensures quick and reliable and at the same time the CAN-bus

simplifies the wiring harness in the vehicle as well as the diagnostic troubleshooting should anything go wrong. This makes maintenanceeasier and less components are required.

• The logic unit is the heart of the control system for the forklift truck, but with a CAN-BUS system, there are more than one independent controller on the Controller Area Network to communicate with each other to control the truck.

• The inverters are connected to each motor.• The logic unit is connected to the other devices.• The MC system units that are located in this network are

• Logics unit• Right Running inverter• Left Running inverter• Pump inverter• Input unit • Left/Right running AC motor• Pump AC motor

4

Major Components Location

Tractors Inverter

Pump Inverter

Steering Hydraulic Priority Valve

Logic Unit

Hydraulic Oil Reservoir

Hyd. Pump and AC Mtr

Traction Line Contactor

Hydraulic Line Contactor

AC Traction Motors

Major Components location1. Traction inverter2. Pump inverter3. Steering hydraulic priority valve4. Logic unit5. Hydraulic oil reservoir6. Hydraulic motor and pump7. Traction line contactor8. Hydraulic line contactor9. AC Traction motors

5

Identification of Control Panel

Left Traction Inverter

Right Traction Inverter

Hydraulic Inverter

Traction Line Contactor

Hydraulic Line Contactor

Identification of control panel1. Left traction inverter2. Right traction inverter3. Hydraulic inverter4. Traction line contactor5. Hydraulic line contactor

6

Outline of Logic unit

• It consists of power card and logic card• Control truck operation based on the operator’s input.• Monitor truck speed and residual battery power• Management role of truck operation control

Model information, fault detection, service management

Outline of Logic unit• This controller includes the power card and logic card• It controls all the jobs for the truck based on the operator’s input

• The controller sends a motor control command to the right and left traction inverter through the input of the direction lever or the accelerator pedal. It also monitors malfunction of the traction system.

• The lever input triggers to send the motor control commands to the pump inverter. It also monitors malfunction in the hydrauliccontrol system. In the FC specifications, this controller sends a control command to the solenoid valves from the output unit by the lever input. A malfunction in the valve control system is also monitored by this controller.

• The truck speed and residual battery power are monitored and shown on this display unit.

• The logic unit sets its model information and optional default data into internal memory. The information is secured when the power supply is turned off. This information is set at the factory.If the truck model information is not set correctly, the truck will not work properly.

7

Main Logic

• Improved serviceability• PDA or Laptop socket via

main logic• DRS switch underneath

footstep• New drive features:

• Boost function• Controlled roll back

• CAN bus electrical system

Main Logic

DRS Switch

Main Logic• Improved serviceability• Laptop socket via main logic• DRS switch underneath footstep• New drive features:

• Boost function• Controlled roll back

• CAN bus electrical system• GSE Connector Cap P/N 97005-18700

8

CAN-bus System

• Data transmission by CAN-Bus system. • CAN-bus ensures quick and reliable control • Simplifies the wiring harness in the vehicle • Easier fault finding

CAN-bus System

Block Diagram of CAN Communication between components• Data transmission by CAN-Bus system. • CAN-bus ensures quick and reliable control • Simplifies the wiring harness in the vehicle • Easier fault finding

9

Model Information

• The data of a group 3 has no default value, but it needs to set data by the actual truck type.

• When you set up for the first time, set up a group 3 first, and then set default data of group 1 and group 2.

• If SUO data is not set, “| |” is displayed.• The model information and various features are set during factory

shipment

NOTICENOTICE

Model Information

Notice:1. The data of a group 3 has no default value, but it needs to set data by the actual

truck type. If the value and the truck model aren’t in agreement, the truck does not operate normally.

2. When you set up for the first time, set up a group 3 first, and then set default data of group 1 and group 2.

3. If SUO data is not set, “| |” is displayed.4. The model information and various features are set during factory shipment.

10

Pictorial of Logic Card

Pictorial of Logic Card

Logic Card and Pin Connectors• CN1 – Logic card side • CN3 – Harness B side• CN2 – Harness B side• CN1 – Harness B side

11

Pictorial of Logic Power Supply Card

Pictorial of Logic Power Supply Card

Power Supply Card and Pin Connectors• CN1 – Power supply card side• CN4 – Harness B side

12

Traction Inverter Decal

Parallel Parallel MosfetMosfet GenerationGeneration InVerterInVerter

GenerationGeneration

Qty of Qty of Mosfet Mosfet Mod.Mod.

Rated input VoltRated input Volt

How to read Traction Inverter DecalPM-1000 AC SystemNew generation controllerMitsubishi Forklift Trucks in-house design. Latest TechnologyMOSFET transistor control: maximum performance, optimum energy use and low operating noise"PM-1000" is a product-name for MITSUBISHI, and "IVA 1-48" is a model-number.*PM-1000 PM from Parallel Mosfet (Power device of main circuit).1000 means the generation.Before, we used the name such as TR-1000, TR-2000, TR-3000 and TR-4000.*IVA1-48IV from InVerter.A means the generation.1 is the quantity of MOSFET module. It means the capacity.48 means rated input voltage.We use one IVA2-48 and two IVA1-48 for 3 wheel AC. The "2" on IVA2 means : two power boards per phase (look at the controller components where you will see for traction only 3 power boards (1 per phase) and 6 power boards for the hydraulic inverter. This one is also bigger by physical size)

13

Hydraulic Inverter Decal

Parallel Parallel MosfetMosfet GenerationGeneration InVerterInVerter

GenerationGeneration

Qty of Qty of Mosfet Mosfet Mod.Mod.

Rated input VoltRated input Volt

How to read Hydraulic Inverter DecalPM-1000 AC SystemNew generation controllerMitsubishi Forklift Trucks in-house design. Latest TechnologyMOSFET transistor control: maximum performance, optimum energy use and low operating noise"PM-1000" is a product-name for MITSUBISHI, and "IVA 1-48" is a model-number.*PM-1000 PM from Parallel Mosfet (Power device of main circuit).1000 means the generation.Before, we used the name such as TR-1000, TR-2000, TR-3000 and TR-4000.*IVA1-48IV from InVerter.A means the generation.1 is the quantity of MOSFET module. It means the capacity.48 means rated input voltage.We use one IVA2-48 and two IVA1-48 for 3 wheel AC. The "2" on IVA2 means : two power boards per phase (look at the controller components where you will see for traction only 3 power boards (1 per phase) and 6 power boards for the hydraulic inverter. This one is also bigger by physical size)

14

Pictorial of Traction Inverter

Pictorial of Traction Inverter• Traction Inverter (Right and Left) with Pin Connectors• Traction Inverter DSP (Digital Signal Processor) Right and Left Inverters with

Pin Connectors• CN2 – Inverter card side• CN7 – Traction right, Harness B side• CN6 – Traction left, Harness B side

15

Pictorial of Pump Inverter

Pictorial of Pump Inverter

• Hydraulic Pump Inverter with Pin Connectors• Hydraulic Pump Inverter DSP (Digital Signal Processor) with Pin Connectors

• CN2 – Inverter card side• CN5 – Harness B side, pump

16

Inverter Discharging Procedure

Inverter discharging procedure :1. Turn off the key switch.2. Disconnect the battery plug.3. Lift up the seat.4. Place a 150Ω/25 W resistor

between P and N terminals in the right traction inverter to discharge electric charges stored in the inverter.

5. After touching resistor to the P and N terminals for approx. 5 sec., measure the voltage between the terminals with a multi-meter and confirm a reading of 5 V or less.

6. Perform the same procedure for left traction inverter and pump inverter in order to discharge electric charge from all inverters.

WARNINGWARNING

BEFORE you start to work on any of the inverters, you MUST discharge the integrated capacitors.DO NOT underestimate the power of these “little” components. Together they can store between 300 ~ 500Amp.Therefore you MUST discharge the capacitors per module before working on them.

The procedure is:• Disconnect the battery connector.• Remove counterweight cover• Use ceramic resistor 0358280 (150Ω / 25W) with two leads and crocodile clips and connect between

the + (POS) and – (NEG) terminal pole.• Wait for approximately 20 ~ 30 seconds for the capacitors to discharge.• Repeat the same for the other inverter modules.

Now you are free to work safely with the controller modules.

Optional you can also use a 48V or 80V work light to discharge the capacitors. The light will also be an indicator if the capacitors are discharged.

17

Removal and Installation Inverter Procedure

Removal1. Raise the front wheels.2. Perform step 1 to 5 in Inverter Discharging Procedure.3. Disconnect all five power cables from P, N, U, V and W terminals. For the

pump inverter, leave P terminal as it is, and disconnect F terminal.4. Disconnect the connector.5. Remove M10 bolts (four places) fixing the inverter, then remove the inverter.

Installation1. Wipe off the dirt and thermal paste from the inverter mounting surface once,

and also remove dirt from the mounting surface and the aluminum base plate of the inverter.

2. Apply thermal paste approx. 1 mm (0.04 in.) thick to the area where the aluminum base plate of the inverter comes into contact with the truck body.

3. Fix the inverter with M10 bolts.4. Connect the power cables to P, N, U, V and W terminals. For the pump inverter,

include F terminal.

18

Replacing DSP Card

Refer to Service Manual

Replacing DSP (Digital Signal Processor) Card

Refer to service manual.

19

Power Board Heat Conducting Paste

The power board is mounted directly to the counterweight.

There are two different types of heat conducting paste for following models:

3 wheeler, AC : Silicone paste(White)

4 wheeler, AC : Heat Cement(Non-hardening graying colour)

CAUTIONSCAUTIONS

Power Board Heat Conducting PasteThe power board is mounted directly to the counterweight.There are two different types of heat conducting paste.BEWARE:On the 3 wheel 48V – AC models : Silicone Paste (white !)On the 4 wheel 48V – AC models : Heat Cement

(non-hardening grayish color)

Reason: the counterweight of the 3 wheel models are machined, so fine surface and the 4 wheel modelsHave a non-machined surface. This results in a much rougher surface and requires the heat-cement.

This is for ALL controller models that are fitted to the counterweight.Do not mix up. Result could be burned-out power boards ! Or overheating conditions.

20

What is Inverter?

The inverter is a motor drive controller that consists of:• Digital Signal Processor (DSP) card,• Insulated Metal Substrate (IMS) module• Drive boards

Using IMS to convert DC power to AC power which features a transformer isolated sine wave output.

It drives the AC induction motors according to the motor control command from the logic unit.

It also monitors malfunctions of motors and its own condition. When a malfunction occurs, it stops the motors and informs to the logic unit.

Traction InverterTraction Inverter

What is Inverter?

The inverter is a motor drive controller that consists of:• Digital Signal Processor (DSP) card,• Insulated Metal Substrate (IMS) module• Drive boards

Using IMS to convert DC power to AC power which features a transformer isolated sine wave output.

It drives the AC induction motors according to the motor control command from the logic unit.

It also monitors malfunctions of motors and its own condition. When a malfunction occurs, it stops the motors and informs to the logic unit.

21

DSP Card

• Is a micro-processor card with digital signal processor.

• Performs adaptive control. • DSPs have the speed

capabilities to concurrently monitor the system and control it.

• A dynamic control algorithm adapts itself in real time to variation in system behaviour.

Traction Inverter, Traction Inverter, DSP CardDSP Card

DSP card• Is a micro-processor card with digital signal processor.• Performs adaptive control.

• DSPs have the speed capabilities to concurrently monitor the system and control it.

• A dynamic control algorithm adapts itself in real time to variation in system behaviour

22

Speed Control of Induction Motors

Speed control of induction motors


23

Insulated Metal Substrate (IMS) Module

MOSFET Banks [One for each phase]

U – Phase connection

V – Phase connection

V – Phase connection

The IMS module has plural MOS-FET modules and converts the battery DC current to AC current for supplying to the drive and pump motors

Traction Inverter, IMSTraction Inverter, IMS

Insulated Metal Substrate (IMS) Module

The IMS module has plural MOS-FET modules and converts the battery DC current to AC current for supplying to the drive and pump motorsAs you see, a different lay-out than the hydraulic version.The traction controller is smaller by dimensions.There are only 3 power boards mounted on this base plate. The U, V and W connections are also lined up differently compared with the hydraulic inverter.

24

MOS-FET

Metal Oxide SemiconductorField Effect Transistor

MOSFET

The MOSFET, or Metal-Oxide-Semiconductor Field-Effect Transistor, is by far the most common field effect transistor in both digital and analog circuits (The 'Metal' in the name is an anachronism from early chips where gates were metal; modern chips use polysilicon gates, but are still called MOSFETs).

The MOSFET is composed of a channel of n-type or p-type semiconductor material and is accordingly called an NMOSFET or a PMOSFET. Usually the semiconductor of choice is silicon.

A MOSFET is a switch with no moving parts that can be turned on and off a a very fast rate.

25

MOS-FET

Metal Oxide Semiconductor Field Effect Transistor

26

MOS-FET

27

MOS-FET

SOURCE (S) and DRAIN (D) are connected with a flexible tube. There is NO flow of water between the GATE (G) and the other twoconnections. This model shows that the SOURCE (S) Collector and DRAIN (D) are fully identical. When the voltage pressure on the GATE (G) connection increases, the flexible hose between the DRAIN (D) and SOURCE (S) is compressed. Result will be a reduction of water flow from DRAIN (D) to SOURCE (S) . With many FET’s the DRAIN and SOURCE are allowed to be reversed.

Note: The design of a transistor allows it to function as an amplifier or a switch. This is accomplished by using a small amount of voltage to control a gate on a much larger supply of electricity, much like turning a valve to control a supply of water.

28

MOS-FET

The PM-1000 AC controller uses solid state MOSFET switches arranged in banks to create the 3 phase supply. These switch about 7000 times per second, making operation very smooth.

The PM-1000 AC controller uses solid state MOSFET switches arranged in banks to create the 3 phase supply. These switch about 7000 times per second, making operation very smooth.

29

Lets take a closer look at the PWM inverter, and discuss some of basic principles.Inverter principle number 1 – A device that changes the battery DC current into alternating current is generally called “Inverter”.The inverter is comprised of two sections;1.) Capacitor bank2.) The Inverter section that changes the DC current to AC current.

So when we call a variable frequency drive an inverter, this is technically incorrect

A device that changes the battery DC current into alternating current is generally called “Inverter.

“PWM Inverter Principle No 1”

ACDCInverterInverter

30

The output transistors of the inverter work like switches. They turn on and off in a specific pattern to produce an output voltage waveform. What we will do is move through the next few screen and watch the switch closures as we progress through time.

Click on the mouse button and watch the switches close ( the closed switches will turn red ).

The output transistors work like switches

S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))

BatteryBatteryT1T1T2T2T3T3


31




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))

DC BusDC BusT1T1T2T2T3T3


S1 S1 –– onon

S6 S6 –– ononS5 S5 –– onon

00 6060

RED Indicates Closed Switch

32




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))



S1 S1 –– onon


00 6060

S2 S2 –– onon

120120


33




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))



00

S1 S1 –– onon


6060

S2 S2 –– onon

120120

S3 S3 –– onon

180180


34




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))



S1 S1 –– onon


6060

S2 S2 –– onon

120120

S3 S3 –– onon

180180

S4 S4 –– onon

24024000


35




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))




S1 S1 –– onon


6060

S2 S2 –– onon

120120

S3 S3 –– onon

180180

S4 S4 –– onon

240240

S5 S5 –– onon

30030000

36




S1S1 S5S5S3S3

S2S2S6S6S4S4

(+)(+)

((--))




S1 S1 –– onon


6060

S2 S2 –– onon

120120

S3 S3 –– onon

180180

S4 S4 –– onon

240240

S5 S5 –– onon

300300

S6 S6 –– onon

36036000

37

The switch pattern that we just demonstrated will produce an output voltage that looks like this, with each waveform being 120 degrees out of phase just like a commercial power supply.

Switch pattern

Resultant output voltage

T1-T2

T2-T3

T3-T1

0 360

S1 S1 –– onon


60

S2 S2 –– onon

120

S3 S3 –– onon

180

S4 S4 –– onon

240

S5 S5 –– onon

300

S6 S6 –– onon

3600


38

The output of a PWM type inverter is both variable frequency and variable voltage. This can be simply explained by what is called a V/f pattern. The V/f pattern sets up a ratio of output voltage to output frequency. You will see a little later that it is very important to keep this ratio constant for optimum motor performance. What this shows me is at 60Hz the output voltage will be 460V and at 1.5Hz the output voltage will be 23V.

Now this question probably comes to mind. A little while ago we said that the DC bus of the PWM inverter was at a fixed level. So how does the inverter vary the output voltage when the DC bus is fixed ?

Well this leads to our next topic, pulse width modulation.

The output voltage changes with frequency

60Hz

460V

230V

30HzTime

Volts

Typical Voltper Hertz

Curve for aStandard460VoltMotor


39

To change the output voltage of the inverter when the pulse amplitude is fixed, the width of the pulse must be adjusted ( or modulated). The higher the ratio of turn on time as compared to the switching time of the transistor, the higher the resultant voltage will be. This method is called pulse width modulation.

“How the output voltage changes if the DC bus voltage is fixed ”

Tc

Ton

TonTc = 50%

Ton: Turn on time of the transistorTc: Switching time


• The output voltage is changed by modulating the width of the output pulses that make up the output waveform

• The higher the ratio of on time as compared to the switching time, the higher the voltage

• This method is called Pulse Width Modulation

40

More on time means higher output voltage

TcTc

TonTon

TcTc

TonTon TonTon

TcTc

TonTonTcTc = 50%= 50%




41


Producing an output waveform

42



43

The method used to produce this pulsed waveform can be simply described. The first step of producing a PWM output waveform begins with the output frequency reference. The output frequency reference is the commanded frequency given to the inverter.



ReferenceSine Wave

ReferenceSine Wave

TriangleCarrier

Frequency

TriangleCarrier

Frequency

Output RMS Voltage

Output RMS Voltage

44

So far we have talked about the V/f pattern of the inverter and that it is important to keep a constant volts per hertz ratio. If we do some investigation, we can see that the V/f ratio at 60Hz is about 7.67 and the ratio at 1.5Hz is about 15.3. This does not look constant to me! Lets look at this a little closer.

Click

Why keep a constant V/f ratio?

Volts

Frequency

460V

23V

1.5Hz 60Hz

460V60Hz

= 7.67

23V1.5Hz = 15.3

“This ratio does not look constant to me”

0


45

This is called an equivalent motor circuit. If you took a 3 phase motor you could represent it with 3 separate equivalent motor circuits. The left portion of the circuit is representative of the stator portion of the motor (consisting of R1- stator resistance, L1-stator inductance , M-mutual inductance). And the right portion of the circuit is representative of the rotor portion of the motor ( consisting of L2-rotor inductance, R2/slip- rotor resistance divided by the motor slip).

Equivalent motor circuit

R1R1L1L1 L2L2

MM R2R2SS


46



R1R1L1 L2

M R2S


460V

47



R1R1L1 L2

M R2S


460V

12V DROP

48



R1R1L1 L2

M R2S


460V

12V DROP

448V

49




R1R1L1 L2

M R2S

460V

12V DROP

448V

448V60Hz

= 7.46

50

This is called an equivalent motor circuit. If you took a 3 phase motor you could represent it with 3 separate equivalent motor circuits. The left portion of the circuit is representative of the stator portion of the motor (consisting of R1- stator resistance, L1-stator inductance , M-mutual inductance). And the right portion of the circuit is representative of the rotor portion of the motor ( consisting of L2-rotor inductance, R2/slip- rotor resistance divided

by the motor slip).


R1R1L1 L2

M R2S


23V

12V DROP

51




R1R1L1 L2

M R2S

23V

12V DROP

11V11V1.5Hz

= 7.34

52

So the voltage and frequency ratios at 1.5Hz and 60Hz are basically the same if you compare the voltage used for producing torque. This constant voltage will produce a constant motor flux in the motor throughout the speed range and Click

Why keep a constant V/f ratio

11V1.5Hz

= 7.34448V60Hz

= 7.46


• A constant V/f ratio produces a constant motor flux

• A constant motor flux produces a constant torque

This leads to the optimum amount of motor torque per amp

53

If the V/f pattern is set improperly, the performance of the motor will suffer. If the V/f ratio is set too low;The motor flux will be reduced which will lead to a reduction of motor torque. This can lead to problems starting the motor or running at low speeds. As well as sluggish response to load changes.

Low voltage to the motor will also cause higher than normal current draw. This condition may lead to motor overheating or inverter overload faults.

Effects of improper V/f ratio


Low V/f ratio results in

• Reduced motor flux which leads to reduced motor torque

• Motor starving for voltage which leads to high current

High V/f ratio results in

• Over saturation condition that leads to high current but no more torque production

• Motor overheating

54

Hydraulic Pump Inverter

Hydraulic (Pump) DC to AC Inverter

View from the top of a Pump DC to AC Inverter

55

Hydraulic Pump Inverter – DSP Card

DSP (Digital Signal Processor) Card Pump Inverter

56

U

v

w

Hydraulic Pump Inverter – IMS Module

MOSFET Banks [Two for each phase]



57

Hydraulic Pump Inverter – Capacitor Bank

Negative Positive

CapacitorBanks

(Qty: 88)

W-Phase

V-Phase

U-Phase

Current Sensor [U]

Current Sensor [V]

Pump and Traction Inverters are not the same.

58

Traction DC to AC Inverter

Traction Inverter

View from the top of a Traction DC to AC Inverter

59

Traction Inverter – DSP card

DSP (Digital Signal Processor) Card Traction Inverter

When ordering this part, you will also get the 4 plastic positioning clips.

60

Traction Inverter

U v w

Traction Inverter – IMS Module

MOSFET Banks [One for each phase]

As you see, a different lay-out than the hydraulic version.The traction controller is smaller by dimensions.There are only 3 power boards mounted on this base plate. The U, V and W connections are also lined up differently compared with the hydraulic inverter.

61

Traction Inverter – Capacitor Bank

Negative

CapacitorBank

(Qty: 40)

Positive

W-Phase

V-Phase

U-Phase

Current Sensor [U]

Current Sensor [W]

Traction Inverter Terminals

62

Typical items to be aware of when working with DC to AC Inverters!!!!!!!!

Go to next slide.

Caution when working on the inverters

The Pump and Traction Inverters have three possible weak points!

63

Inverter’s weak points

Inverter’s weak pointsa) 10-line flat cable can be pinched between plastic top cover and heatsink.b) Incorrect terminal torque on phase connection result in excessive heat or

breakage of PCB (Printed Circuit Board)c) Incorrect heatsink paste resulting in burned power boards

64

Phases Terminal Torque!!

M8 Nut11.77 ± 1.96 N.m1.20 ± 0.20 kgf.m8.68 ± 1.45 lb.ft

Use the correct terminal torque !!WARNINGWARNING

In case you over tighten the U, V and – or W terminal torque, the following issue will happen:

Fault code will be displayed on your operator display or even a burned inverter could occur.When you over-tighten, the thread-end could break inside the plastic stud, resulting in bad contact with buss bar.In the other case the buss-bar W phase will be forced out and the small PCB (Printed Circuit Board) studs will bent and snap the board.In these cases you will NOT have any warranty !! Be aware, these are high costs repairs !!

65

Typical Over Current Damage to MOSFET’s

Over Current to MOS-FET

“Punch-through” of the FET’s .This is a typical defect caused by over current on the FET’s.

66

Ribbon Cables Pinched

Traction or Hydraulic Pump InvertersWatch that ribbon cables are not pinched when cover is

installed!!!!!!!!!!!

Be aware there is a chance for the flat cables to be pinched between the plastic cover and The base plate – heatsink.

67

Terminal on Contactor Coils

“X” and “Y” terminal on contactor coils

Traction line contactor coil:

Red = wire 249Green = wire 247

Pump contactor coil:

Red = wire 250Black = wire 248

Wire 249 & 250 are joined and connected together to CN1-63 of the master logics (con VE)Wire 247 is connected to CN1-59Wire 248 is connected to CN1-60

See next slide for wiring schematic.

68

Correct Connection of wires

Line and Pump Contactor Wiring Schematic

Correct connection of wires is critical to correct contactor operation.

69

Connection for Main Harness & GSE plug

Connection for Main harness and GSE plug

Master Logic CardMaster Logic Card

The fuse holder, the GSE connector and the logic card power & in-outputs are allSeparate connectors to Harness B.

70

Know your forklift Truck

Controlled Rollback Function

When the accelerator pedal is released on a grade, regeneration braking is applied and the truck goes down slowly.If the operator leaves the operator’s seat for approximately 3 seconds and truck speed is lower than 0.5km/h, motor power is shifted to neutral and the regeneration braking does not work.When the motor is overheated, the regeneration braking is restricted and the going down speed is increased

Controlled roll back with regeneration function

1.Lever regen.When:(1)Direction lever is in F or R(opposite direction against the truck movement)

(2)Acceleration pedal is ON(3)Regardless of BRAKE pedal

Regeneration: According to accel. pedal and SUO #22

2.Auto regenYou can select ACCEL. regen or BRAKE regen by SUO #21

2.1 ACCEl. regenWhen:(1)Direction lever is in F or R

(2)Acceleration pedal is OFF(3)Regardless of BRAKE pedal

Regeneration: Constant. According to SUO #232.2 BRAKE regen

When:(1)Direction lever is in F or R(2)Acceleration pedal is OFF(3)Press the BRAKE pedal

Regeneration: Constant. According to SUO #23

3.Controlled roll backWhen:(1)Direction lever is in F or R

(2)Acceleration pedal is OFF(3)Truck speed is slow enough ( < 0.2km/h)

71

Trouble Shooting

1. Talk to the Operator.2. Perform an Operational Check to verify the Operators description.3. Visually inspect Cables, Connectors, Contactor Tips etc.4. Perform a basic Battery cable to frame resistance test. (must be at

least 20kΩ) Panel negative to frame and all fuses to frame.5. Check the Battery condition. (Not less that 2.0 volts per cell at rest

voltage)6. Always check each option & write down the finding.7. Carry out Self Diagnostics & write down the findings.8. Write down any stored Error Codes from the History Folder.9. Verify any carried out repairs

Testing Tools: a)Circuit tester b) Clamp meter c) IC clipTesting Tools: a)Circuit tester b) Clamp meter c) IC clip

Note Red Letter.

Basic Check


Always follow basic troubleshooting steps.• Talk to the operator.• Confirm his description of the problem with an operational check.• Visually inspect cables, connectors, contactor tips, etc.• Perform basic battery cables to frame resistance test. (at least 20 k ohm)

Panel negative to frame and all fuses to frame.• Check battery condition. (Not less that 2.0 volts per cell at rest voltage)Always check each option and write down the reading.Testing Tools(a) Circuit tester(b) Clamp meter(c) IC clipNote Red Letters

72

Any Questions?Any Questions?

tab005 - 3w_ac_mit_control system.pdf

Documents

traction line contactor8

traction line contactor5

bus system

inverter controller

hydraulic motor

hydraulic line contactor9

right traction inverter3

left traction inverter2