GE SX Series Installation And Operation Manual

INSTALLATION AND OPERATION

SX TRANSISTOR CONTROL Page 1

SEPARATELY EXCITED (SX) TRANSISTORIZED TRACTION MOTOR CONTROL

AND SERIES PUMP MOTOR CONTROL

INSTALLATION AND OPERATION MANUAL

(GE Models IC3645SR5W606F1 [software rev. BL3C and higher] and IC3645SP5U600F1)

Note: The information contained herein is intended to assist OEM's, Dealers and Users of electric vehicles
in the application, installation and service of GE solid-state controllers. This manual does not purport to
cover all variations in OEM vehicle types. Nor does it provide for every possible contingency to be met
involving vehicle installation, operation or maintenance. For additional information and/or problem
resolution, please refer the matter to the OEM vehicle manufacturer through his normal field service
channels. Do not contact GE directly for this assistance.

Table of Contents

General Electric Company May 2003

Section 1.0 INTRODUCTION .........................................................................................................................................................4

1.1 Motor Characteristics...............................................................................................................4

1.2 Solid-State Reversing................................................................................................................5

1.3 Flexible System Application..................................................................................................... 5

1.4 More Features with Fewer Components.................................................................................5

Section 2.0 FEATURES OF SX FAMILY OF MOTOR CONTROLLERS .....................................................................................6

2.1 Performance .............................................................................................................................. 6

2.1.1 Oscillator Card Features...................................................................................................6

2.1.1.a Standard Operation...................................................................................................6

2.1.1.b Creep Speed...............................................................................................................6

2.1.1.c Controlled Acceleration ...........................................................................................6

2.1.2 Current Limit.......................................................................................................................6

2.1.3 Braking................................................................................................................................6

2.1.3.a Regenerative Braking to Zero Speed.......................................................................6

2.1.3.b Pedal Position Plug Braking..................................................................................... 6

2.1.3.c Auto Braking .............................................................................................................. 6

2.1.4 Auxiliary Speed Control ....................................................................................................6

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Table of Contents ( Continued )

2.1.4.a Field Weakening ................................................................................................................6

2.1.4.b Speed Limits ...................................................................................................................... 7

2.1.5 Ramp Operation.................................................................................................................7

2.1.5.a Ramp Start..................................................................................................................7

2.1.5.b Anti-Rollback..............................................................................................................7

2.1.6 On-Board Coil Drivers and Internal Coil Suppression .................................................7

2.2 System Protective Override......................................................................................................7

2.2.1 Static Return to Off (SRO) ................................................................................................7

2.2.2 Accelerator Volts Hold Off ...............................................................................................7

2.2.3 Pulse Monitor Trip (PMT)................................................................................................. 7

2.2.4 Thermal Protector (TP)................................... ..................................................................7

2.2.5 Low Voltage .......................................................................................................................7

2.3 Diagnostics................................................ ................................................................................8

2.3.1 Systems Diagnostics......................................................................................................... 8

2.3.2 Status Codes......................................................................................................................8

2.3.2.a Standard Status Codes........................................ ..................................................... 8

2.3.2.b Stored Status Codes .................................................................................................8

2.3.3 Hourmeter Readings .........................................................................................................8

2.3.3.a Maintenance Alert and Speed Limit ....................................................................... 8

2.3.4 Battery Discharge Indication (BDI)................................................................................. 8

2.3.4.a Internal Resistance Compensation ..................... ...........................................................8

2.3.5 Handset ..............................................................................................................................8

2.3.6 RS-232 Communication Port ............................... ............................................................8

2.3.6.a Interactive Dash Display Modes ................... ................................................................8

2.3.7 Circuit Board Coil Driver Modules...................................................................................9

2.3.8 Truck Management Module (TMM)................................................................................ 9

2.4 Hydraulic Pump Control............................................................................................................9

Section 3.0 ORDERING INFORMATION, ELEMENTARY AND OUTLINE DRAWINGS ......................................................10

3.1 Ordering Information for Separately Excited Controls .................................................................10

3.2 Outline: SX-4 and SR-4 Package Size............................................................................................. 11

3.3 Outline: SX-3 and SR-3 Package Size............................................................................................. 12

3.4 Traction Elementary.......................................................................................................................... 13

3.5 Pump Elementary...............................................................................................................................14

3.6 Traction and Pump Control Input / Output List.............................................................................. 15

Section 4.0 TROUBLESHOOTING AND DIAGNOSTIC STATUS CODES ..............................................................................16

4.1 General Maintenance Instructions .................................................................................................16

4.2 Cable Routing and Separation ................................................................................................ 16

4.2.1 Application Responsibility................................................................................................ 16

4.2.2 Signal/Power Level Definitions................................................................................................ 16

4.2.2.a Low Level Signals (Level L)...............................................................................................16

4.2.2.b High Level Signals (Level H)............................................................................................. 17

4.2.2.c Medium-Power Signals (Level MP)................................................................................. 17

4.2.2.d High-Power Signals (Level HP)........................................................................................17

4.2.3 Cable Spacing Guidelines.........................................................................................................17

4.2.3.a General Cable Spacing ..................................................................................................... 17

4.2.4 Cabling for Vehicle Retrofits ....................................................................................................17

4.2.5 RF Interference .......................................................................................................................... 17

4.2.6 Suppression............................................................................................................................... 17

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Table of Contents ( Continued )

4.3 Recommended Lubrication of Pins and Sockets Prior to Installation........................................18

4.4 Controller Mounting Guidelines.......................................................................................................19

4.4.1 Necessary Tools........................................................................................................................ 19

4.4.2 The GE Control Mounting Surface ..........................................................................................19

4.4.3 Vehicle Mounting Surface........................................................................................................19

4.4.4 Application of Thermal Compound..........................................................................................19

4.4.5 Mounting the GE Control..........................................................................................................20

4.4.6 Maintenance.............................................................................................................................. 20

4.5 General Troubleshooting Instructions............................................................................................ 20

4.6 Traction Controller Status Codes.................................................................................................... 22-39

4.7 TMM Module Status Codes .............................................................................................................39-41

4.8 Pump Control Status Codes .............................................................................................................42-52

Section 5.0 SX FAMILY - GE HANDSET INSTRUCTIONS.......................................................................................................53

5.1 General Features .............................................................................................................................. 53

5.2 Purpose/Setup Functions ...............................................................................................................53

5.3 Setup Function Procedures .............................................................................................................54

5.3.1 Setup Mode ............................................................................................................................... 54

5.3.2 Status Code Scrolling.................................. .............................................................................54

5.3.3 SX Handset Plug Connections & Outline Drawing................................................................54

5.4 Setup Functions for Traction Controller ........................................................................................55-60

5.5 Summary of Current Limit Adjustments..........................................................................................61

5.6 Setup Functions for Hydraulic Pump Controller............................................................................62-64

Section 6.0 AUTO CALIBRATION OF ACCELERATOR POTENTIOMETERS................................................. ........................65

Section 7.0 TRACTION MEMORY MAP......................................................................................................................................66-68

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SX TRANSISTOR CONTROL Page 4

Section 1. INTRODUCTION

Section 1.1 Motor Characteristics

The level of sophistication in the controllability of traction
motors has changed greatly over the past several years.
Vehicle manufacturers and users are continuing to expect
more value and flexibility in electric vehicle motor and
control systems as they are applied today. In order to
respond to these market demands, traction system
designers have been forced to develop new approaches to
reduce cost and improve functions and features of the
overall system. Development is being done in a multi-

current to increase, providing the greater torque needed to
drive the increased mechanical load. If the mechanical
load is decreased, the process reverses. The motor speed
and the back EMF increase, while the armature current and
the torque developed decrease. Thus, whenever the load
changes, the speed changes also, until the motor is again
in electrical balance.

In a shunt motor, the variation of speed from no load to
normal full load on level ground is less than 10%. For this
reason, shunt motors are considered to be constant speed
motors (Figure 2).

generational format that allows the market to take
advantage of today’s technology, while looking forward to

SPEED

new advances on the horizon. GE has introduced a second
generation system using separately excited DC shunt
wound motors. The separately excited DC motor system
offers many of the features that are generally found on the
advanced AC systems. Historically, most electric vehicles
have relied have on series motor designs because of their
ability to produce very high levels of torque at low speeds.

NO LOAD CURRENT

TORQUE

FULL

LOAD CURRENT

STARTING

CURRENT

But, as the demand for high efficiency systems increases,
i.e., systems that are more closely applied to customers’
specific torque requirements, shunt motors are now often
being considered over series motors. In most applications,
by independently controlling the field and armature
currents in the separately excited motor, the best attributes
of both the series and the shunt wound motors can be
combined.

In the separately excited motor, the motor is operated as a
fixed field shunt motor in the normal running range.
However, when additional torque is required, for example,

ARMATURE CURRENT

Figure 2

to climb non-level terrain, such as ramps and the like, the
field current is increased to provide the higher level of
torque. In most cases, the armature to field ampere turn

SPEED

ratio can be very similar to that of a comparable size series
motor (Figure 3.)

FULL

NO LOAD CURR ENT

TORQUE

STARTING

LOAD CURRENT

CURRENT

SPEED

ARMATURE CURRENT

Figure 1

As shown in from the typical performance curves of Figure
1, the high torque at low speed characteristic of the series
motor is evident.

In a shunt motor, the field is connected directly across the
voltage source and is therefore independent of variations in
load and armature current. If field strength is held
constant, the torque developed will vary directly with the
armature current. If the mechanical load on the motor
increases, the motor slows down, reducing the back EMF
(which depends on the speed, as well as the constant field
strength). The reduced back EMF allows the armature

FULL

LOAD CURRENT

NO LOAD CURRENT

TORQUE

ARMATURE CURRENT

Figure 3

STARTING

CURRENT

Aside from the constant horsepower characteristics
described above, there are many other features that
provide increased performance and lower cost. The

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following description provides a brief introduction to
examples of some of these features.

Section 1. 2 Solid-State Reversing

The direction of armature rotation on a shunt motor is
determined by the direction in which current flows through
the field windings. Because of the of the shunt motor field
only typically requires about 10% of the armature current at
full torque, it is normally cost effective to replace the
double-pole, double-throw reversing contactor with a low
power transistor H-Bridge circuit (Figure 4).

armature, the motor performance curve can be maximized
through proper control application.

Section 1. 4 More Features with Fewer Components

Field weakening with a series wound motor is
accomplished by placing a resistor in parallel with the field
winding of the motor. Bypassing some of the current
flowing in the field into the resistor causes the field current
to be less, or weakened. With the field weakened, the motor
speed will increase, giving the effect of “overdrive”. To
change the “overdrive speed”, it is necessary to change

the resistor value. In a separately excited motor,
independent control of the field current provides for

LINE

FUSE

CAP

POS

A1 +

Q2

ARM

A2 -

Q1

Q3

Q4

Q5

F2F1

Q6

infinite adjustments of “overdrive” levels, between
motor base speed and maximum weak field. The
desirability of this feature is enhanced by the
elimination of the contactor and resistor required for
field weakening with a series motor.

With a separately excited motor, overhauling speed
limit, or downhill speed, will also be more constant. By
its nature, the shunt motor will try to maintain a
constant speed downhill. This characteristic can be
enhanced by increasing the field strength with the
control. Overhauling load control works in just the

NEG

Figure 4

By energizing the transistors in pairs, current can be made
to flow in either direction in the field. The armature control
circuit typically operates at 12KHZ to 15KHZ, a frequency
range normally above human hearing. This high frequency
coupled with the elimination of directional contactors,
provides very quiet vehicle operation. The field control
circuits typically operate at 2 KHZ.

The line contactor is normally the only contactor required
for the shunt motor traction circuit. This contactor is used
for both pre-charge of the line capacitors and for
emergency shut down of the motor circuit, in case of
problems that would cause a full motor torque condition.
The line can be energized and de-energized by the various
logic combinations of the vehicle, i.e. activate on key, seat
or start switch closure, and de-energize on time out of idle
vehicle. Again, these options add to the quiet operation of
the vehicle.

Section 1. 3 Flexible System Application

Because the shunt motor controller has the ability to
control both the armature and field circuits independently,
the system can normally be adjusted for maximum system
efficiencies at certain operating parameters. Generally
speaking, with the ability of independent field and

opposite way of field weakening, armature rotation
slows with the increase of current in the field.

Regenerative braking (braking energy returned to the
battery) may be accomplished completely with solid-state
technology. The main advantage of regenerative braking is
increased motor life. Motor current is reduced by 50% or
more during braking while maintaining the same braking
torque as electrical braking with a diode clamp around the
armature. The lower current translates into longer brush
life and reduced motor heating. Solid state regenerative
braking also eliminates a power diode, current sensor and
contactor from the circuit.

For GE, the future is now as we make available a new
generation of electric traction motor systems for electric
vehicles having separately excited DC shunt motors and
controls. Features that were once thought to be only
available on future AC or brushless DC technology vehicles
systems are now achievable and affordable.

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Section 2. FEATURES OF SX FAMILY OF TRANSISTOR
MOTOR CONTROLLERS

Section 2.1 Performance

Section 2.1.1 Oscillator Card Features

Section 2.1.1.a Standard Operation

With the accelerator at maximum ohms or volts, the creep
speed can be adjusted by Function 2 of the Handset or a
trimpot. The field control section allows the adjustment of
the field weakening level in order to set the top speed of the
motor. This top speed function (Minimum Field Current) is
enabled when the armature current is less than the value
set by Function 24 and the accelerator input voltage is less
than 1 volt. Top Speed can be adjusted by Function 7 of the
Handset or a trimpot.
The percent on-time has a range of approximately 0 to 100
percent. The SX controllers operate at a constant
frequency and the percent on-time is controlled by the
pulse width of the voltage / current applied to the motor
circuits.

Section 2.1.1.b Creep Speed

With the accelerator at maximum ohms or volts
(approximately 3.7 to 3.5 VDC), the creep speed can be
adjusted by Function 2 of the Handset. At creep speed, the
ON time can decrease to approximately 5%, with the OFF
time at approximately 95%. At full transistor operation, this
condition will be reversed (short OFF time, long ON time).
This variation of ON and OFF time of the oscillator varies
the voltage applied to the motor, thereby varying the speed
of the motor for a given load.

Section 2.1.1.c Control Acceleration

This feature allows for adjustment of the rate of time it
takes for the control to accelerate to 100% applied battery
voltage to the motor on hard acceleration. Armature C/A is
adjusted by Function 3 from 0.1 to 22 seconds.

Section 2.1.2 Current Limit

This circuit monitors motor current by utilizing sensors in
series with the armature and field windings. The
information detected by the sensor is fed back to the card
so that current may be limited to a pre-set value. If heavy
load currents are detected, this circuit overrides the
oscillator and limits the average current to a value set by
Function 4 and Function 8 of the Handset. The C/L setting is
based on the maximum thermal rating of the control.
Because of the flyback current through 3REC, the motor
current is usually greater than battery current, except at
100% ON time.

Section 2.1.3 Braking

Section 2.1.3.a Regenerative Braking to Zero Speed

Slow down is accomplished when
reversing direction by providing a
small amount of retarding torque for

Q2

deceleration. If the vehicle is
moving, and the directional lever is

ARM

moved from one direction to the
other, the regen signal is initiated.

Q1

Figure 5

Once the regen signal has been
initiated, the field current is
increased (armature circuit shown in

Figure 5). Armature current is
regulated to the regen current limit as set by Function 9. As
the vehicle slows down, the field current continues to
increase, and transistor Q2 begins to chop. The field
current will increase until it reaches a preset value set by
Function 10, and transistor Q2 on-time will increase until it
reaches 100% on-time. Once both of the above conditions
have been met, and regen current limit can no longer be
maintained, the braking function is canceled. The fields
will then reverse, and the control reverts back to motoring.
Part of the energy produced by the motor during regen is
returned to the battery, and part is dumped in the motor as
heat.

Section 2.1.3.b Pedal Position Regenerative Braking

This feature allows control of the plugging distance based
on pedal position when there has been a “directional
switch" change. Pedal position will reduce the regenerative
current to the "value set by this function" as the accelerator
is returned to the creep speed position. Maximum regen
current is obtained with the accelerator in the top speed
position.

Section 2.1.3.c Auto Braking

This feature is enabled by initiating a "neutral position"
using either the directional switch or the accelerator
switch. Once activated, Auto Braking operates similar to
Pedal Position Plug Braking and is adjusted by using
Function 21 of the Handset.

Section 2.1.4 Auxiliary Speed Control

Section 2.1.4.a Field Weakening

This function allows the adjustment of the field weakening
level in order to set the top speed of the motor. The function
is enabled when the armature current is less than the value
set by Function 24 and the accelerator input voltage is set
for max speed. It is important to note that this function is
used to optimize motor and control performance, and this
setting will be determined by GE and OEM engineers at the

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SX TRANSISTOR CONTROL Page 7

time of vehicle development. This setting must not be
changed by field personnel, without the permission of the
OEM.

Section 2.1.4.b Speed Limits

This feature provides a means to control speed by limiting
motor volts utilizing three "adjustable speed limits. This
motor volt limit regulates top speed of the transistor
controller, but actual truck speed will vary at any set point
depending on the loading of the vehicle. Each speed limit
can be adjustable with the Handset using Functions 11, 12,
and 13.

Section 2.1.5 Ramp Operation

Section 2.1.5a Ramp Start

This feature provides maximum control torque to restart a
vehicle on an incline. The memory for this function is the
directional switch. When stopping on an incline, the
directional switch must be left in its original or neutral
position to allow the control to initiate full power when
restarted. The accelerator potentiometer input will
modulate ramp start current.

Section 2.1.5b Anti-Rollback

This feature provides retarding torque to limit rollback
speed in the non-travel direction when the ACC pedal is
released when stopping on a grade, or when the brake
pedal is released when starting on a grade. This feature
forces the vehicle to roll very slowly down the grade when
accelerator or brake is released. Because the vehicle can
gain significant speed during roll-back, the torque needed
to re-start on the ramp is lower than an unrestricted roll­back speed.

Section 2.1.6 On-Board Coil Drivers & Internal Coil
Suppression

Coil drivers for the LINE contactor and fan motor are on­board the control card. This contactor must have a coil
rated for the vehicle battery volts, and the fan should also
be rated for battery volts.

Section 2.2 System Protective Override

Section 2.2.1 Static Return to Off (SRO)

This inherent feature of the control is designed to require
the driver to return the directional lever to the neutral
position anytime he leaves the vehicle and returns.
Additionally, if the seat switch or key switch is opened, the
control shuts off and cannot be restarted until the
directional lever is returned to neutral. A time delay of
approximately 2 seconds is built into the seat switch input

to allow momentary opening of the seat switch, if a bump is
encountered.

Section 2.2.2 Accelerator Volts Hold Off

This feature checks the voltage level at the accelerator
input whenever the key switch or seat switch is activated.
If, at start up, the voltage is less than 1.8 volts, the control
will not operate. This feature assures that the control is
calling for low speed operation at start up.

Section 2.2.3 Pulse Monitor Trip (PMT)

The PMT design contains three features which shut down,
or lock out, control operation if a fault conditions occurs
that would cause a disruption of normal vehicle operation:

· Look ahead

· Look again

· Automatic look again and reset

The PMT circuit will not allow the control to start under the
following conditions:

· The control monitors both armature and field FET's at

start-up and during running.

· The control will not allow the line contactor to close at

start-up, or will drop it out during running, if either the
armature or field FET's are defective, so as to cause
uncontrolled truck movement.

Section 2.2.4 Thermal Protector (TP)

This temperature sensitive device is internal to the power
transistor (Q1) module. If the transistor's temperature
begins to exceed the design limits, the thermal protector
will lower the maximum current limit, and maintain the
transistors within their temperature limits. Even at a
reduced current limit, the vehicle will normally be able to
reach sufficient speed. As the control cools, the thermal
protector will automatically reset, returning the control to
full power.

Section 2.2.5 Low Voltage

Batteries under load, particularly if undersized or more
than 80 percent discharged, will produce low voltages at
the control terminals. The SX control is designed for use
down to 50 percent of a nominal battery voltage of 36-84
volts, and 75 percent of a nominal battery voltage of 24
volts. Lower battery voltage may cause the control to
operate improperly, however, the resulting PMT should
open the Line contactor, in the event of a failure.

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SX TRANSISTOR CONTROL Page 8

Section 2.3 Diagnostics

Section 2.3.1 Systems Diagnostics

The control detects the system's present operating status
and can be displayed to either the Dash Display or the
Handset. There are currently over 70 status codes that are
available with SX systems using Traction and Pump
controls and Truck Management Module (TMM). Along
with the status code display from the TMM, the SX control
is capable of reducing the current to the motor, alerting the
operator of a critical fault condition.

Section 2.3.2 Status Codes

Section 2.3.2a Standard Status Codes

The SX traction control has over 30 Status Codes that
assist the service technician and operator in trouble
shooting the vehicle. If mis-operation of the vehicle occurs,
a status code will be displayed on the Dash Display for
vehicles so equipped, or be available by plugging the
Handset into the “y” plug of the logic card.
With the status code number, follow the procedures
outlined in DIAGNOSTIC STATUS CODES to determine the
problem and a solution.

Note: The Status Code Instruction Sheets do not claim to
cover all possible causes of a display of a "status code ".
They do provide instructions for checking the most direct
inputs that can cause status codes to appear.

Section 2.3.2.b Stored Status Codes

This feature records the last 16 "Stored Status Codes" that
have caused a PMT controller shut down and/or disrupted
normal vehicle operation. (PMT type faults are reset by
cycling the key switch). These status codes, along with the
corresponding BDI and hourmeter readings, can be
accessed with the Handset, or by using the RS 232
communications port and dumping the information to a
Personal Computer terminal.

Section 2.3.3 Hourmeter Readings

This feature will display the recorded hours of use of the
traction and pump control to the Dash Display each time
the key switch is turned off.

Section 2.3.3.a Maintenance Alert & Speed Limit

This feature is used to display Status Code 99 and/or
activate a speed limit when the vehicle operating hours
match the hours set into the maintenance alert register.
This feature is set with the Handset using Functions 19 and

20. The operator is alerted that maintenance on the vehicle
is required.

Section 2.3.4 Battery Discharge Indication (BDI)

The latest in microprocessor technology is used to provide
accurate battery state of charge information and to supply
passive and active warning signals to the vehicle operator.
Features and functions:

· Displays 100 to 0 percent charge.

· Display blinks with 20% charge. Disables pump circuit

with 10% charge. Auto ranging for 36/48 volt operation.
Adjustable for use on 24 to 48 volts.

Section 2.3.4.a Internal Resistance Compensation

This feature is used when the Battery Discharge Indicator
is present. Adjustment of this function will improve the
accuracy of the BDI.

Section 2.3.5 Handset

This is a multi-functional tool used with the LX, ZX, and SX
Series GE solid state controls. The Handset consists of a
Light Emitting Diode (LED) display and a keyboard for data
entry. Note, for ordering purposes, a separate Handset part
is required for SX controls.

Features and functions:

· Monitor existing system status codes for both traction

and pump controls. Monitor intermittent random status
codes.

· Monitor battery state of charge, if available.

· Monitor hourmeter reading on traction and pump

controls. Monitor or adjust the control functions.

Section 2.3.6 RS 232 Communication Port

This serial communication port can be used with
Interactive Custom Dash Displays to allow changes to
vehicle operating parameters by the operator. Or, it can be
used by service personnel to dump control operating
information and settings into a personal computer program.

Section 2.3.6.a Interactive Dash Display
Modes

The Interactive Custom Dash Display allows the operator to
select the best vehicle performance for changing factory
(task) conditions. There are four (4) "operator interaction
modes" that can be selected by depressing a push button
on the dash display.

From the Dash Display, the operator may select any of four
pre-set interactive modes consisting of (4) Min Field levels,
(4) Field Weakening levels, (4) Ratio levels, and (4) Regen
Current Limit levels.
These interactive modes are "pre-set" using the Handset
(Functions 48-63) or a personal computer (Functions 97-

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SX TRANSISTOR CONTROL Page 9

112). This feature allows the operator to select the best
vehicle performance for changing factory (task) conditions.

Section 2.3.7 Circuit Board Coil Driver Modules

The Coil drivers are internal to the control card, and are the
power devices that operate the Line contactor coil. On
command from the control card, these drivers initiate
opening and closing the contactor coils. All driver modules
are equipped with reverse battery protection, such that, if
the battery is connected incorrectly, the contactors can not
be closed electrically.

Section 2.3.8 Truck Management Module (TMM)

The Truck Management Module is a multifunction
accessory card, or an integral function of the GE Pump
controls when used with the SX Traction control. The
Module provides the OEM the ability to initiate status codes
or operator warning codes to be displayed on the Dash
Display, whenever a normally open switch or sensor wire
provides a signal to the Module.

The TMM Module can be used to display a separate status
code indicating over-temperature of traction motors,
hydraulic motors, or any other device or system that can
activate a switch that closes.

The TMM Module can also be used as a Brush Wear
Indicator (BWI). The Brush Wear Indicator is designed to
detect a "worn out brush" and display a fault code on the
Dash Display to warn maintenance personnel that the
motor brushes need to be replaced before they wear to the
point of causing destructive damage to the motor
commutator surface.

Section 2.4 Hydraulic Pump Control

This hydraulic motor controller consists of the following
features:

· Four speeds, adjustable from O to 100% on.

· Fixed speeds actuated by switch closure to negative.

· Current limit and controlled acceleration adjustable.

· Battery Discharge Indicator interrupt compatible.

· 0 – 100% on, controlled by accelerator voltage (P7).

Operation of voltage regulator card: This card provides the
basic functions required for controlling the pump control,
optional contactors, and PMT functions. Battery positive is
applied through a main control fuse to the key switch,
energizing the control card power supply input to P1.

When a pump contactor is used, PMT operation is the
same as outlined for the traction controllers.

The four speed reference points P12, P19, P20 and P21 are
selected by connecting these points independently to
battery negative.

The first speed is obtained by closing Speed Limit I (P12) to
control negative. SLl is adjustable by Function 11 using the
Handset to adjust percent on from O to 100%. The specified
motor volts will be regulated, however, the magnitude of
motor current will vary depending on the loading of the
vehicle.

The second speed is obtained by closing SL2 (P19) to
control negative. SL2 is adjusted using the Handset and
Function 12 similar to SL1.

The third speed is obtained by closing SL3 (P20) to control
negative. SL3 is adjusted using the Handset and Function
13 similar to SL1.

The fourth speed is obtained by closing SL4 (P21) to control
negative. SL4 is adjusted using the Handset and Function
14 similar to SL1.

If more than one Speed Limit is activated, the selected
speed with the highest motor volts will override the low
motor volt speed. The current limit circuit is adjustable and
operates the same as the traction current limit.

The controlled acceleration circuit is adjustable and
operates the same as the traction circuit. Adjustment range
is from 0.1 to 5.5 seconds.

The Battery Discharge Indicator (BDI) interrupt will disable
the hydraulic controller if the connection at P10 loses the
12 volt signal from the traction control. BDI interrupt can be
disabled by Function 17 using the Handset. Select card type
with or without BDI function.

RevisedMay 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 10

Section 3.0 ORDERING INFORMATION, ELEMENTARY AND OUTLINE DRAWINGS

Section 3.1 Ordering Information for Separately Excited Controls

Example:

Part Number: IC3645 SE 4 D 33 2 C3

Argument Number: 01 02 03 04 05 06 07

Argument 01: Basic Electric Vehicle Control Number

Argument 02: Control Type:

SP = Series Control (Pump)
SH = Separately Excited Control ( Plugging )
SR = Separately Excited Control ( Regen to Zero )

Argument 03: Operating Voltage:

1 = 120 volts 4 = 48 volts
2 = 24 volts 5 = 36/48 volts
3 = 36 volts 6 = 24/36 volts
7 = 72/80 volts

Argument 04: Package Size:

D = 6.86” X 6.67”
R = 6.86” X 8.15”
U = 8.66” X 8.13”
W = 8.66” X 10.83”

Argument 05: Armature Current
( 2 characters )

22 = 220 Amps
33 = 330 Amps
40 = 400 Amps
etc.

Argument 06: Field Current
( 1 character )
2 = 20 Amps
3 = 30 Amps
4 = 40 Amps
etc.

Argument 07: Customer / Revision

A1 = Customer A / Revision 1
B1 = Customer B / Revision 1
etc.

Revised May 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 11

Section 3.2 Outline: SX-4 and SR-4 Package Size

Revised May 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 12

Section 3.3 Outline: SX-3 and SR-3 Package Size

Revised May 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 13

Section 3.4 Traction Elementary

P21

P4 P5

P6

P17 P2

P18

NEG

P14

P23P22

MOTOR

TACH SIGNAL

SENSOR INPUT

+12V TACH

P20

P10

P8

P13

TRACTION CONTROL PLUG PL-2

P9

TEMPERATURE

FROM TRACTION

*

P7

P1

OPEN INPUT OR

SIGNAL DISABLED

VOLTAGE > 3V = BDI

TEMPERATURE INPUT

FROM PUMP CONTROL;

CUSTOMER SUPPLIED

MOTOR CONNECTIONS

*

CONTROLLER

BDI INTERRUPT TO JOY STICK

ACCEL SWITCH

*

ARMATURE

*

2W

2.2K

*

REV

FWD

*

BRAKE SWITCH

DIRECT

SEAT SWITCH

*

*

SWITCH

PARK BRAKE

SWITCH

L

*

FAN

A1

24V

*

KEY SWITCH

FAN ENABLE

FU1

F1

*

FIELD

F2

*

CONNECTION

CONTROL POWER

POS A1 F1

NEG A2 F2

*

A2

*

FU3

LINE

*

FU5

+

-

*

Revised May 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 14

Section 3.5 Pump Elementary

SPEED 1

SPEED 2

PUMP CONTROL TEMP

ACCEL POT INPUT

P7

P18

*

L

P2

FU4

P12

P17

P3

P1

STATUS CODE 93 INPUT

*

P

P4

P5P6P8

STATUS CODE 93 INPUT

STATUS CODE 94 INPUT

P19

STATUS CODE 94 INPUT

STATUS CODE 95 INPUT

P9

STATUS CODE 95 INPUT

P15

STATUS CODE 92 INPUT

P21

P20

STATUS CODE 90 INPUT

PUMP CONTROL PLUG PL-2

P13

P16

P14

P11

OVER TEMP OUTPUT

BRUSH WEAR OUTPUT

STATUS CODE 91 INPUT

A1

SPEED 3

SPEED 4

*

A1

A1

P

*

FU2

*

*

*

*

SUPPLIED BY CUSTOMER

POWER CONNECTION

*

*

A2

ARMATURE

PUMP CONTROL

POWER CONNECTION

FIELD

A2

A2N

N

LINE

*

CONTACTOR

KEY SW.

BATT (+)

BATT (-)

Revised May 2003

OUTLINE DRAWINGS, ELEMENTARY DRAWINGS AND INPUTS/OUTPUTS

SX TRANSISTOR CONTROL Page 15

Section 3.6 Traction and Pump Control Input and Output List

CONNECTIONS TO MAIN PLUG (23 PIN) AND "Y" PLUG (12 PIN)

TRACTION PUMP

PIN INPUT/OUTPUT DESCRIPTION INPUT/OUTPUT DESCRIPTION

1 BATTERY VOLTS FROM BATTERY BATTERY VOLTS FROM BATTERY
2 BATTERY VOLTS FROM KEY BATTERY VOLTS FROM KEY
3 BATTERY VOLTS FROM START SWITCH -OPTIONAL STATUS CODE 93 INPUT
4 BATTERY VOLTS FROM FORWARD SWITCH -OPTIONAL STATUS CODE 93 INPUT
5 BATTERY VOLTS FROM REVERSE SWITCH -OPTIONAL STATUS CODE 94 INPUT
6 BATTERY VOLTS FROM SEAT SWITCH STATUS CODE 94 INPUT
7 ACCELERATOR INPUT VOLTAGE SIGNAL POTENTIOMETER INPUT VOLTAGE SIGNAL
8 ACCELERATOR NEGATIVE STATUS CODE 95 INPUT

9 ACCELERATOR POT +5 VOLTS SUPPLY STATUS CODE 95 INPUT
10 BDI INTERRUPT PUMP ENABLE SIGNAL 12VDC
11 PLUG/RGN OUTPUT SIGNAL +12V 1=PLUG STATUS CODE 91 INPUT
12 NOT USED SPEED LIMIT #1 INPUT
13 AUX ACCELERATOR INPUT TMM1 BRUSHWEAR INDICATER OUTPUT
14 LINEAR TRACTION MOTOR TEMPERATURE TMM1 OVER TEMPERATURE OUTPUT
15 NOT USED STATUS CODE 92 INPUT
16 NOT USED STATUS CODE 90 INPUT
17 LINE CONTACTOR DRIVER AND SUPPRESSION LINE CONTACTOR DRIVER
18 FAN PUMP CONTROL TEMPERATURE 0 = COLD
19 NOT USED SPEED LIMIT #2 INPUT
20 TEMPERATURE FROM PUMP CONTROL SPEED LIMIT #3 INPUT
21 PARK BRAKE (NEG=SL1) SPEED LIMIT #4 INPUT
22 TACH +12V SERIAL RECEIVE
23 TACH INPUT SERIAL TRANSMIT

MOTOR PROPORTIONING "Y" PLUG PUMP "Y" PLUG

PIN INPUT/OUTPUT DESCRIPTION INPUT/OUTPUT DESCRIPTION

1 CLOCK (OUT) CLOCK (OUT)

2 DATA (OUT) DATA (OUT)

3 ENABLE (OUT) ENABLE (OUT)

4 NEGATIVE NEGATIVE

5 +5V SUPPLY +5V SUPPLY

6 CONT/STORE (IN) (HANDSET) CONT/STORE (IN) (HANDSET)

7 NOT USED NOT USED

8 BWI INPUT/VALUE VALUE

9 OVER TEMP INPUT/FUNCTION FUNCTION
10 NOT USED NOT USED
11 SERIAL RECEIVE / CONNECT TO P22 SERIAL RECEIVE / CONNECT TO P22
12 SERIAL TRANSMIT / CONNECT TO P23 SERIAL TRANSMIT / CONNECT TO P23

1 2 3 4 5 6

7 8 9 10 11 12

WIRE END VIEW "Y" PLUG

1 2 3 4 5 6 6 8

9 10 11 12 13 14 15

16 17 18 19 20 21 22 23

WIRE END VIEW - MAIN PLUG

* Pins 3, 4 and 5
These input functions are provided by the
accelerator pot input value.

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 16

Section 4.0 TROUBLESHOOTING AND DIAGNOSTIC STATUS CODES

Section 4.1 General Maintenance Instructions

The transistor control, like all electrical apparatus, does
have some thermal losses. The semiconductor junctions
have finite temperature limits, above which these devices
may be damaged. For these reasons, normal maintenance
should guard against any action which will expose the
components to excessive heat and/or those conditions
which will reduce the heat dissipating ability of the control,
such as restricting air flow.

The following Do’s and Don’t’s should be observed:

Any controls that will be applied in ambient temperatures
over 100° F (40° C) should be brought to the attention of the
vehicle manufacturer.

All external components having inductive coils must be
filtered. Refer to vehicle manufacturer for specifications.

The wiring should not be directly steam cleaned.

areas, blow low-pressure air over the control to remove
dust. In oily or greasy areas, a mild solution of detergent or
denatured alcohol can be used to wash the control, and
then low-pressure air should be used to completely dry the
control.

For the control to be most effective, it must be mounted
against the frame of the vehicle. The metal vehicle frame,
acting as an additional heat sink, will give improved vehicle
performance by keeping the control package cooler. Apply

a thin layer of heat-transfer grease (such as Dow Corning

340) between the control heat sink and the vehicle frame.

Control wire plugs and other exposed transistor control
parts should be kept free of dirt and paint that might
change the effective resistance between points.

CAUTION: The vehicle should not be plugged when the
vehicle is jacked up and the drive wheels are in a free
wheeling position. The higher motor speeds can create
excessive voltages that can be harmful to the control.

Do not hipot (or megger) the control. Refer to control
manufacturer before hipotting.

Use a lead-acid battery with the voltage and ampere hour
rating specified for the vehicle. Follow normal battery
maintenance procedures, recharging before 80 percent
discharged with periodic equalizing charges.

Visual inspection of GE contactors contained in the traction
and pump systems is recommended to occur during every
160 hours of vehicle operation. Inspection is recommended

In dusty

to verify that the contactors are not binding and that the
tips are intact and free of contaminants.

GE does not recommend that any type of welding be
performed on the vehicle after the installation of the
control(s) in the vehicle. GE will not honor control failures
during the warranty period when such failures are
attributed to welding while the control is installed in the
vehicle.

Section 4.2 Cable Routing and Separation

Electrical noise from cabling of various voltage levels can
interfere with a microprocessor-based control system. To
reduce this interference, GE recommends specific cable
separation and routing practices, consistent with industry
standards.

Section 4.2.1 Application Responsibility

The customer and customer’s representative are
responsible for the mechanical and environmental
locations of cables. They are also responsible for applying
the level rules and cabling practices defined in this section.
To help ensure a lower cost, noise-free installation, GE
recommends early planning of cable routing that complies
with these level separation rules.

On new installations, sufficient space should be allowed to
efficiently arrange mechanical and electrical equipment.

On vehicle retrofits, level rules should be considered during
the planning stages to help ensure correct application and
a more trouble-free installation.

Section 4.2.2. Signal/Power Level Definitions

The signal/power carrying cables are categorized into four
defining levels: low, high, medium power, and high power.
Within those levels, signals can be further divided into
classes.

Sections 4.2.2.a through 4.2.2.d define these levels and
classes, with specific examples of each. Section 4.2.3
contains recommendations for separating the levels.

4.2.2.a Low-Level Signals (Level L)

Low-level signals are designated as level L. These consist
of:

· Analog signals 0 through ±15 V

· Digital signals whose logic levels are less than 15 V DC

· 4 – 20 mA current loops

· DC busses less than 15 V and 250 mA

The following are specific examples of level L signals used
in drive equipment cabling:

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 17

· Control common tie

· DC buses feeding sensitive analog or digital hardware

· All wiring connected to components associated with

sensitive analog hardware with less than 5V signals (for

example, potentiometers and tachometers)

· Digital tachometers and resolvers

· Dash display cabling

· RS-232 cabling

Note: Signal inputs to analog and digital blocks should be
run as shielded twisted-pair (for example, inputs from
tachometers, potentiometers, and dash displays).

4.2.2.b High-Level Signals (Level H)

High-level signals are designated as level H. These signals
consist of:

· Analog and digital signals greater than 15 V DC and

less than 250 mA

For example, switch inputs connected to battery volts are
examples of level H signals used in drive equipment
cabling.

4.2.2.c Medium-Power Signals (Level MP)

Medium power signals are designated as level MP. These
signals consist of:

· DC switching signals greater than 15 V

· Signals with currents greater than 250 mA and less than

10A

The following are specific examples of level MP signals
used in drive equipment cabling:

· DC busses less than 10 A

· Contactor coils less than 10 A

· Machine fields less than 10 A

4.2.2.d. High Power Signals (Level HP)

Power wiring is designated as level HP. This consists of DC
buses and motor wiring with currents greater than 10 A.
The following are specific examples of level HP signals
used in drive equipment cabling:

· Motor armature loops

· DC outputs 10 A and above

· Motor field loops 10 A and above

4.2.3. Cable Spacing Guidelines

Recommended spacing (or clearance) between cables (or
wires) is dependent on the level of the wiring inside them.
For correct level separation when installing cable, the

customer must apply the general guidelines (section

4.2.3.a), outlined below.

4.2.3.a General Cable Spacing

The following general practices should be used for all
levels of cabling:

· All cables and wires of like signal levels and power

levels must be grouped together.

· In general, different levels must run in separate wire

bundles, as defined in the different classes, identified
above. Intermixing cannot be allowed, unless noted by
exception.

· Interconnecting wire runs should carry a level

designation.

· If wires are the same level and same type signal, group

those wires from one location to any other location
together in multiconductor cables or bind them
together with twine or zip-ties.

· When unlike signals must cross, cross them in 90°

angles at a maximum spacing. Where it is not possible
to maintain spacing, place a grounded steel barrier
between unlike levels at the crossover point.

4.2.4 Cabling for Vehicle Retrofits

Reducing electrical noise on vehicle retrofits requires
careful planning. Lower and higher levels should never
encircle each other or run parallel for long distances.
It is practical to use existing wire runs or trays as long as
the level spacing (see section 4.2.2) can be maintained for
the full length of the run.

Existing cables are generally of high voltage potential and
noise producing. Therefore, route levels L and H in a path
separate from existing cables, whenever possible.

For level L wiring, use barriers in existing wire runs to
minimize noise potential.

Do not loop level L signal wires around level H, level MP, or
HP wires.

4.2.5 RF Interference

To prevent radio frequency (RF) interference, care should
be taken in routing power cables in the vicinity of radio­controlled devices.

Section 4.2.6 Suppression

Unless specifically noted otherwise, suppression (for
example, a snubber) is required on all inductive devices
controlled by an output. This suppression minimizes noise
and prevents damage caused by electrical surges.

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 18

Section 4.3 Recommended Lubrication of Pins and
Sockets Prior to Installation

Beginning in January of 1999, GE will implement the
addition of a lubricant to all connections using pins and
sockets on EV100/EV200 and Gen II products. Any
connection made by GE to the A, B, X, Y, or Z plugs will
have the lubricant NYE 760G added to prevent fretting of
these connections during vehicle operation.

Fretting occurs during microscopic movement at
the contact points of the connection. This movement
exposes the base metal of the connector pin which, when
oxygen is present, allows oxidation to occur. Sufficient
build up of the oxidation can cause intermittent contact
and intermittent vehicle operation. This can occur at any
similar type of connection, whether at the control or in any
associated vehicle wiring, and the resultant intermittent
contact can provide the same fault indication as actual
component failure.

The addition of the NYE 760G lubricant will prevent
the oxidation process by eliminating the access of oxygen
to the contact point. GE recommends the addition of this
lubricant to the 12 pin and 23 pin plugs of all new Gen II
controls at the time of their installation into a vehicle

When servicing existing vehicles exhibiting
symptoms of intermittent mis-operation or shutdown by the
GE control, GE recommends the addition of this lubricant to
all 12 and 23 pin plugs, after proper cleaning of the
connectors, as a preventative measure to insure fretting is
not an issue before GE control replacement. Also, for long
term reliable control operation, the plug terminals must be
maintained per these instructions with the recommended
contact cleaner and lubricant which provides a high
degree of environmental and fretting protection.

New and re-manufactured control plugs are cleaned and
lubricated prior to shipment from the factory. However, in
applications where severe vibration or high temperature
cycling and excessive humidity ( such as freezers ) are
present, it is recommended that the plug terminals be
cleaned and lubricated every year, per this instructions. In
normal applications, plug maintenance should be
performed every two years, unless intermittent problems
arise with the plugs, requiring more immediate attention.

Warning: Do not use any other cleaners or lubricants
other than the ones specified.

WARNING: Before conducting maintenance on the
vehicle, jack up the drive wheels, disconnect the battery
and discharge the capacitors. Consult the Operation and
Service Manual for your particular vehicle for details on
discharging the capacitors; this procedure differs
between SCR and Transistor controls.

1. Disconnect plug from controller or mating plug.

2. Locate the plug that contains the socket (female)

terminals. Maintenance needs only to be performed on

the plug containing the socket (female) type terminals.
Reconnecting the plugs will lubricate the pin (male)
terminals.

3. Clean each terminal using Chemtronics

â contact

cleaner “Pow-R-WasH CZ “ as shown in Figure 1.

s

c

i

n

o

r

t

m

e

h

C

r

e

n

a

e

l

c

t

c

a

t

n

o

c

Z

C

­H

R

-

s

a

w

o

W

P

e

n

a

z

o

r

i

c

Figure 1

4. Lubricate each terminal using Nye

â 760G lubricant as

shown in figure 2. Apply enough lubricant to each
terminal opening to completely fill each opening to a
depth of .125” minimum.

Nye

LU

B

RICA

N

TS

Figure 2

5. Reconnect plugs.

Reference

Cleaner Chemtronics

â Pow-R-WasH CZ Contact

Cleaner

Lubricant Nye

â Lubricants NYOGELâ 760G

GE Plug Lub Kit Contains both above products:
328A1777G1

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 19

Section 4.4 Controller Mounting Guidelines

In the design of the GE family of motor controls,
performance assumptions were made based on heat
transfer between the control and the ambient environment.
The vehicle mounting surface acts as a heat sink, which
increases the effective surface area for heat dissipation. If
this assumed heat transfer is not achieved during control
installation and operation, GE controllers will fall short of
their anticipated performance. It should be noted that the
condition of the mounting surface, and the quality of the
resulting interface between the control and the vehicle, can
significantly hinder heat transfer from the control. The
presence of contaminants, or of air voids created by
surface inconsistencies in either the vehicle or the control,
degrade the control’s capacity for heat transfer. The
control’s performance is de-rated proportionally as its own
thermal sensors reduce its operation to protect it from
damage due to excessive heating.

Contained within the software of the GE controls are
several diagnostic status codes related to controller
thermal performance. Failure to follow these mounting
recommendations increases the likelihood of encountering
these status codes, through no fault of the control itself,
thus voiding controller warranty for units returned solely
due to the presence of these status codes.

Careful surface preparation, including adequate
application of thermal compound, as detailed in the
following paragraphs, must be completed during the
installation of GE controls. There are many techniques for
applying thermal compound, and we have outlined one
approach below that has shown to apply a consistent
thickness of material.

Section 4.4.1 Necessary Tools

GE recommends the use of the following components, or
equivalent substitutions, during the control installation
process:

a) Thermal compound, (Dow Corning #340),

maintained per the manufacturer’s
recommendations and free of contaminants

b) 3/32” notched trowel, such as a Krusin

adhesive spreader, model 00031

c) Calibrated torque wrench (0 – 15 ft-lbs)

Section 4.4.2 The GE Control Mounting Surface
During the manufacture of the GE control, the surface
flatness is maintained at 0.005” per linear inch (not to
exceed 0.025” per 10.0 inches). The surface finish of the GE
control has an R

(average roughness) of 64 (microinches),

a

or better. This finish is consistent with cold rolled or
extruded aluminum.

Care should always be taken in the handling and storage of
controllers. The base of the control should be free from
nicks, bumps, protrusions or any other foreign object that

would prevent the control from sitting flush with the vehicle
mounting surface. Examine the base of the control to verify
that it is in good condition and free from damage or
contamination.

Section 4.4.3 Vehicle Mounting Surface
The quality of the vehicle mounting surface is critical for
the optimum heat transfer between the control and the
ambient environment. Conduction through the base of the
control is the control’s only means of heat rejection. While
GE controls are highly efficient, a few percent of the
electrical energy will be converted into heat. As previously
mentioned, if this energy is not dissipated through the base
of the control, a thermal protector will reduce the
performance of the control until the temperature stabilizes.

For optimal heat transfer from control to vehicle, the
flatness of the vehicle mounting surface should be
equivalent to the flatness of the control surface (0.005” per
linear inch). Use a straight edge or dial indicator to verify
the mounting surface.

The biggest hindrance to heat transfer is the presence of
rust, scale, weld splatter or paint on the vehicle mounting
surface. If any of these items are noted, prepare the
surface per the following guidelines:

a) Clean the mounting surface with a rotary wire

brush until the metal surface is exposed.

b) Using 80-100 grit emery paper, sand the

surface until the metal shines.

c) Flush the surface clean with an appropriate

liquid de-greaser or parts cleaner.

Section 4.4.4 Application of Thermal Compound

Due to the minute differences in the control mounting
surface and the vehicle mounting surface, small pockets of
air will be created. These air pockets will add to the overall
thermal resistance of the interface.

To avoid these air pockets and improve thermal
conductivity, thermal compound must be applied between
the GE control base plate and the vehicle mounting surface.
The function of this compound is to conform to surface
discrepancies, filling gaps and optimizing the metal-to­metal contact of the control and the vehicle.

a) Prepare the two mounting surfaces (control

and vehicle) as indicated above.

b) Using a triangular notched trowel of 3/32”

(.09” +/- .01), apply the grease to the vehicle
mounting surface.

c) Use straight, non-crossing strokes of the

trowel to apply the compound.

d) Make multiple vertical passes until a uniform

consistency is achieved.

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 20

1 4

1 3

Krusin adhesive spreader model 00031

Vehicle surface after proper grease application

Section 4.4.5 Mounting the GE Control
a) Place the control unit with desired orientation on

mounting plate with mounting holes aligned.

b) Move the control slightly in all directions to eliminate

voids and enhance the distribution of the thermal
compound.

c) Insert the all of the mounting hardware (4, 6 or 8 bolts,

M6 or M8, necessary for the mounting of the
respective family of controls).

d) Tighten these bolts (as per sequence shown in

diagrams below) to half of the nominal torque value

(7.5lb-ft).

e) Lastly, tighten the bolts to the nominal torque value (15

lb-ft), following the same sequence.

Calibrated torque wrench for hardware installation

2

4

2

6

5

1

3

3 2

8

2

4

6

Proper sequence for use in tightening hardware during

control mounting

Section 4.4.6 Maintenance

If it is necessary to remove the control for service, careful
consideration must be given to removing the old thermal
compound from the control and mounting surface, prior to
replacement of the unit. Never re-use thermal compound.
Use a putty knife or similar straight edge to carefully
remove all thermal compound residue without damaging
either mounting surface. Flush the surfaces with a liquid
de-greaser or parts cleaner and allow them to dry, before
re-applying the thermal compound and mounting the
control. Take care not to contaminate the surfaces with
hydraulic fluid or battery acid.

Section 4.5 General Troubleshooting Instructions

Trouble-shooting the SX family of controls should be quick
and easy when following the instructions outlined in the
following status code instruction sheets.

If mis-operation of the vehicle occurs, a status code will be
displayed on the Dash Display (for vehicles equipped with a
Dash Display) or made available by plugging a Handset into
the plug "Y" location, and then reading the status code.

Note: Status code numbers from 00 to 99 are traction
control status codes. Status codes with the prefix 1 (101 to

199) are pump control status codes.

5

3

1

7

Revised May 2003

DIAGNOSTIC STATUS CODES

SX TRANSISTOR CONTROL Page 21

With the status code number, follow the procedures
outlined in the status code instruction sheets to determine
the problem.

Important Note: Due to the interaction of the logic card
with all vehicle functions, almost any status code or
control fault could be caused by the logic card. After all
other status code procedures have been followed and no
problem is found, the controller should then be replaced as
the last option to correct the problem.

The same device designations have been maintained on
different controls but the wire numbers may vary. Refer to
the elementary and wiring diagrams for your specific
control. The wire numbers shown on the elementary
diagram will have identical numbers on the corresponding
wiring diagrams for a specific vehicle, but these numbers
may be different from the numbers referenced in this
publication.

WARNING: Before trouble-shooting, jack up the drive
wheels, disconnect the battery and discharge the
capacitors. Reconnect the battery as needed for specific
checks. Capacitors should be discharged by connecting a
200 ohm 2 watt resistor between the positive and negative
terminals on the control panel.

Check resistance on R x 1000 scale from frame to power
and control terminals. A resistance of less than 20,000
ohms can cause misleading symptoms. Resistance less
than 1000 ohms should be corrected first.

Before proceeding, visually check for loose wiring,
mis-aligned linkage to the accelerator switch, signs of
overheating of components, etc.

Tools and test equipment required are: clip leads, volt-ohm
meter (20,000 ohms per volt) and basic hand tools.

Revised May 2003