GE IC3645SR4R404U2 User manual

INSTALLATION AND OPERATION
SX TRANSISTOR CONTROL Page 1
October 1998
SEPARATELY EXCITED(SX) TRANSISTORIZED DUAL MOTOR TRACTION CONTROLLERS
AND SERIES PUMP CONTROL
INSTALLATION AND OPERATION MANUAL
(IC3645SR4R404U2 and IC3645SP4R400U2)
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.
Copyright by General Electric Company October 1998
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 ....................................................................................5
2.1 Performance.............................................................................................................................. 5
2.1.1 Oscillator Card Features.................................................................................................. 5
2.1.1.a Standard Operation..................................................................................................6
2.1.1.b Proportional Operation for Dual Motor Vehicles.................................................. 6
2.1.1.c Creep Speed............................................................................................................... 6
2.1.1.d Control Acceleration and 1ATime.......................................................................... 6
2.1.2 Current Limit...................................................................................................................... 6
2.1.3 Braking............................................................................................................................... 7
2.1.3.a Plug Braking.............................................................................................................. 7
2.1.3.b RegenerativeBraking to Zero Speed...................................................................... 7
2.1.3.c Pedal Position Plug Braking.................................................................................... 7
2.1.3.d Auto Braking.............................................................................................................. 7
2.1.3.e Brake Pedal Regenerative Braking......................................................................... 7
2.1.4 Auxiliary Speed Control.................................................................................................... 7
2.1.4.a Field Weakening........................................................................................................ 7
2.1.4.b Speed Limits .............................................................................................................. 7
2.1.5 Ramp Operation ................................................................................................................ 8
Table of Contents

INSTALLATION AND OPERATION
SX TRANSISTOR CONTROL Page 2
October 1998
2.1.5.a Ramp Start................................................................................................................. 8
2.1.5.b Anti-Rollback............................................................................................................. 8
2.1.6 Steer Pump Contactor Time Delay ................................................................................. 8
2.1.7 On-Board Coil Drivers and Internal Coil Suppression ................................................. 8
2.2 System Protective Override..................................................................................................... 8
2.2.1 Static Return to Off (SRO) ............................................................................................... 8
2.2.2 Accelerator Volts Hold Off............................................................................................... 8
2.2.3 Pulse Monitor Trip (PMT)................................................................................................. 8
2.2.4 1A Current Drop Out......................................................................................................... 8
2.2.5 Thermal Protector (TP)..................................................................................................... 8
2.2.6 Low Voltage ...................................................................................................................... 8
2.3 Diagnostics................................................................................................................................ 9
2.3.1 Systems Diagnostics........................................................................................................ 9
2.3.2 Status Codes...................................................................................................................... 9
2.3.2.a Standard Status Codes............................................................................................. 9
2.3.2.b Stored Status Codes ................................................................................................ 9
2.3.3 Hourmeter Readings ........................................................................................................ 9
2.3.4 Battery Discharge Indication (BDI)................................................................................9
2.3 .4.a Internal Resistance Compensation ........................................................................ 9
2.3.5 Handset ............................................................................................................................. 9
2.3.6 RS-232 Communication Port ........................................................................................... 9
2.3.6.a Interactive Dash Display Modes............................................................................. 9
2.3.7 Circuit Board Coil Driver Modules.................................................................................. 10
2.3.8 Truck Management Module (TMM)............................................................................... 10
2.4 Hydraulic Pump Control........................................................................................................... 10
Section 3.0 ORDERING INFORMATION, ELEMENTARY AND OUTLINE DRAWINGS......................................................11
3.1 Ordering Information for Separately Excited Controls......................................................... 11
3.2 Outline: SX-2 Package Size...................................................................................................... 12
3.3 Outline: SR-2 Package Size..................................................................................................... 13
3.4 Dual Motor Proportioning Drive Elementary......................................................................... 14
3.5 Standard Pump Elementary..................................................................................................... 15
3.6 Dual Motor Proportioning Drive Input / Output List.............................................................. 16
Section 4.0 TROUBLESHOOTING AND DIAGNOSTIC STATUS CODES..............................................................................17
4.1 General Maintenance Instructions......................................................................................... 17
4.2 Cable Routing and Separation ............................................................................................... 17
4.2.1 Application Responsibility............................................................................................... 17
4.2.2 Signal/Power Level Definitions........................................................................................ 17
4.2.2.a Low Level Signals (Level L)...................................................................................... 17
4.2.2.b High Level Signals(Level H)..................................................................................... 18
4.2.2.c Medium-Power Signals (Level MP)........................................................................ 18
4.2.2.d High-Power Signals (Level HP) ............................................................................... 18
4.2.3 Cable Spacing Guidelines................................................................................................ 18
4.2.3.a General Cable Spacing............................................................................................. 18
4.2.4 Cabling for Vehicle Retrofits............................................................................................ 18
4.2.5 RF Interference.................................................................................................................. 18
4.2.6 Suppression....................................................................................................................... 18
4.3 Recommended Lubrication of Pins and Sockets Prior to Installation................................ 19
4.4 General Troubleshooting Instructions................................................................................... 19
4.5 Traction Controller Status Codes............................................................................................ 20-34
4.6 TMM Status Codes................................................................................................................... 35-38
Table of Contents ( Continued )

INSTALLATION AND OPERATION
SX TRANSISTOR CONTROL Page 3
October 1998
4.7 Pump Control Status Codes..................................................................................................... 39-48
Section 5.0 TRUCK MANAGEMENT MODULE (TMM)............................................................................................................49
5.1 General Features ...................................................................................................................... 49
5.2 Operation .................................................................................................................................. 49
5.3 Installation ................................................................................................................................ 49
5.4 Connection Diagram................................................................................................................. 49
5.4.1. TMM7A Card Connections.............................................................................................. 49
5.4.2. Typical Brush Wear Sensor Connections...................................................................... 49
5.4.3. TMM Pump Control Connections.................................................................................... 50
5.4.4. Typical Brush Wear Sensor Connectionsfor Pump Control....................................... 50
5.5 TMM7A Outline Drawings....................................................................................................... 50
Section 6.0 SX FAMILY - GE HANDSET INSTRUCTIONS ......................................................................................................51
6.1 General Features ...................................................................................................................... 51
6.2 Purpose/Setup Functions ........................................................................................................ 51
6.3 Setup Function Procedures .................................................................................................... 52
6.3.1 Setup Mode ............................................ .......................................................................... 52
6.3.2 Status Code Scrolling....................................................................................................... 52
6.3.3 SX Handset Plug Connections & Outline Drawing.... ...................................................52
6.4 Setup Functions for Traction Controller ................................................................................ 53-59
6.5 Summary of Current Limit Adjustments.................................................................................. 60
Section 7.0 DISPLAYS...................................................................................................................................................................61
7.1 Application ................................................................................................................................ 61
7.2 Standard Dash Displays .................................. ....................................................................... 61
7.3 Interactive Custom Dash Displays.......................................................................................... 61
7.3.1 Connections....................................................................................................................... 61
7.3.2 Par t Numbers................................................................................................................... 61
7.3.3 Connector Reference Numbers....................................................................................... 62
7.4 Start-up Display Sequence ..................................................................................................... 62
7.5 Outline Drawings ........................................ ............................................................................. 62
Section 8.0 TURN ANGLE POTENTIOMETER INSTALLATION..............................................................................................63
8.1 General....................................................................................................................................... 63
8.2 270 Degree Potentiometer Input ............................................................................................. 64
8.3 Turn Angle Input Volts vs. Steer Wheel Degrees vs. Handset Reading............................. 65
Section 9.0 MEMORY MAPS........................................................................................................................................................66
9.1 Typical Memory Map for DM Proportioning Control........................................................... 66-68
Table of Contents ( Continued )

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 4
October 1998
Section 1. INTRODUCTION
Section 1.1 Motor Characteristics
The level of sophistication in thecontrollability oftraction
motors has changed greatly over the past several years.
Vehiclemanufacturers and users are continuing to expect
more value and flexibility in electric vehiclemotor and
control systems as they are applied today. In order to
respond to these market demands, traction system
designers havebeen forced to develop new approaches to
reduce cost and improve functions and features of the
overall system. Development is being done in a multi-
generational format that allows the market to take
advantage of today’s technology, whilelooking forward to
new advances on thehorizon. GE has introduced a second
generation system using separately excited DC shunt
wound motors. The separately excited DC motor system
offers many ofthe featuresthat are generally found on the
advanced AC systems. Historically, most electric vehicles
have relied have on series motor designs because of their
abilityto produce very high levels oftorque at low speeds.
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 theseparately excited motor, the bestattributes
of both the series and theshunt wound motors can be
combined.
NO LOAD CURRENT
FULL
LOAD CURRENT
STARTING
CURRENT
ARMATURE CURRENT
Figure 1
SPEED
TORQUE
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 themechanical load on the motor
increases, themotor 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
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 areconsidered to be constantspeed
motors (Figure 2).
NO LOAD CURRENT
FULL
LOAD CURRENT
STARTING
CURRENT
ARMATURE CURRENT
Figure 2
SPEED
TORQUE
In the separately excited motor, the motor is operated as a
fixed field shunt motor in the normal running range.
However, when additional torqueis required, for example,
to climb non-level terrain, such as ramps and the like, the
field currentis increased to provide the higher level of
torque. In most cases, the armature to field ampere turn
ratio can be very similar to that of a comparablesize series
motor (Figure 3.)
NO LOAD CURRENT
FULL
LOAD CURRENT
STARTING
CURRENT
ARMATURE CURRENT
Figure 3
SPEED
TORQUE
Aside from the constant horsepower characteristics
described above, there are many other features that
provide increased performanceand lower cost. The

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 5
October 1998
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-throwreversing contactor with a low
power transistor H-Bridge circuit (Figure 4).
By energizing the transistors in pairs, current can bemade
to flow in either direction in the field. The field and
armature control circuits typically operate at 12KHZ to
15KHZ, a frequency range normally above human hearing.
This high frequency coupled with the elimination of
directional contactors, provides very quietvehicle
operation.
The line contactor is normally the only contactor required
for the shunt motor traction circuit. This contactor is used
for both pre-charge ofthe 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 beenergized and de-energized by the various
logic combinations of thevehicle, i.e. activate on key, seat
or start switch closure, and de-energize on time outof idle
vehicle. Again, these options add to thequiet 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 theability of independentfield and
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
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
opposite way of field weakening, armature rotation
slows with the increase of current in the field. An
extension of this feature is a zero-speed detect feature
which prevents the vehicle from free-wheeling down
an incline, should the operator neglect to set the brake.
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 shuntmotors and
controls. Features that were once thought to be only
available on futureAC or brushless DC technology vehicles
systems are now achievable and affordable.
Section 2. FEATURES OF SX FAMILY OF TRANSISTOR
MOTOR CONTROLLERS
Section 2.1 Performance
Section 2.1.1 Oscillator Card Features
FUSE
LINE
CAP ARM F2F1
Q2
Q4
Q3
Q5
Q1
POS
NEG
Figure 4
A1 +
A2 -
Q6

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 6
October 1998
Section 2.1.1.a Standard Operation
The oscillator section of thecard has two adjustable
features, creep speed and minimum field current. With the
accelerator at maximum ohms or volts, the creep speed
can be adjusted by Function 2 of theHandset or a trimpot.
The field control section allows the adjustment ofthe field
weakening level in order to set thetop 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 inputvoltage is less than 1
volt. Top Speed can beadjusted by Function 7 ofthe
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 thepercent on-time is controlled by the
pulse width of the voltage / current applied to the motor
circuits.
Section 2.1.1.b Proportional Operation for Dual Motor
Vehicles
A key performance advantage of this control is the ability to
achieveactual "proportioning" of motor speed. In a
non-proportioning, or single control, system when the
vehicle starts to turn, the outside drive wheel turns in a
larger circle than the inside wheel. Depending on the
geometry of the vehicle, at some degree of turn angle, the
inside wheel must slow down to prevent scrubbing of the
wheel. This is accomplished on single control system by
disconnecting the inside motor and letting the wheel "free
wheel" or "float" at whatever speed is dictated by the
outside wheel that is still under power. The main
disadvantage of this system isthat no torque is available on
that motor when the inside wheel is in the "free-wheel"
mode, and performance in a turn is reduced. When the
steer wheel nears to the 90° turn angle, the inside motor is
re-connected in the opposite direction of the outside. At
this point, torque is returned to the inside wheel and the
speed is the same on both motors.
With two controls, the speed of each motor can be
regulated independently. The driver controls the speed of
the outside wheel with the accelerator input signal. The
inside wheel speed is controlled by the turn angle of the
steer wheel. A potentiometer is attached to the steer wheel
in order to communicate the steer angle to the controllers.
During vehicle manufacture, software selection identifies
each control for its application as a right or left control.
The controls are physically identical, and it is only software
that separates a right from a left control or differentiates a
control for a dual motor application from one intended for a
single motor vehicle. As the steer reaches some
pre-selected turn angle, approximately 20o, the speed of the
inside wheel decrease proportionally to the speed of the
outside wheel. This proportional declinewill continueon a
linear path until the steer angle reaches another pre-
determine angle of, approximately 65o.
At this point, the inside wheel will stop, as the steer angle is
increased toward the 90° point, the inside wheel will
reverse direction and startto accelerate proportionally in
speed. As the steer angle reaches the 90° point, the inside
wheel speed will be the same as that of the outside wheel.
During this entire turn, except for several degrees when the
motor was stopped to change direction, torque was always
present on theinside wheel, providing a smoother ride
throughout the turning radius of the vehicle.
Details for adjustment of the steer angle potentiometer can
be found in Appendix A of this manual.
0
O
10
O
10
O
20
O
20
O
30
O
30
O
40
O
40
O
50
O
50
O
60
O
60
O
70
O
70
O
80
O
80
O
90
O
100%
50%
50%
100%
90
O
100%
50%
50%
100%
RIGHT
MOTOR LEFT MOTOR
STEERING ANGLE
LEFT
TURN RIGHT
TURN
LEFT
MOTOR RIGHT MOTOR
RIGHT
CONTROL
LEFT
CONTROL
0
O
90
O
90
O
REV - SPEED - FWD REV - SPEED - FWD
Section 2.1.1.c 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
timeat 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.d Control Acceleration and lA Time
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. ThelA contactor
will automatically close 0.2 seconds after the controlled
acceleration stops and the accelerator input is less than
0.5 volts or less than 200 ohms. 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 backto the card
so that current may be limited to a pre-set value. If heavy
load currents are detected, this circuitoverrides the
oscillator and limits the average currentto a value set by

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 7
October 1998
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 isusually greater than battery current, exceptat
100% ON time, or when the lA contactor is closed.
Section 2.1.3 Braking
Section 2.1.3.a Plug Braking
Slow down is accomplished when reversing direction by
providing a small amount of retarding torque for
deceleration. If the vehicle is moving, and the directional
lever ismoved from one direction to the other, theplug
signal is initiated. Once the plug signal has been initiated,
the field is reversed, and the armature current is regulated
to the plug currentlimit as setby Function 6. Armature
current is regulated by increasing the field current as the
vehicle slows down. Once the field current reaches a
preset value, set by Function 10, and armature plug current
can no longer be maintained, the braking function is
canceled, and the control reverts back to motoring.
All energy produced by themotor during plugging is
dumped as heatin the motor in this braking mode.
Section 2.1.3.b Regenerative Braking to Zero Speed
Slow down is accomplished when
reversing direction by providing a
small amount of retarding torquefor
deceleration. If the vehicle is
moving, and thedirectional lever is
moved from one direction to the
other, the regen signal is initiated.
Once the regen signal has been
initiated, the field current is
increased. Armature current is
regulated to the regen current limit
as set by Function 9. As the vehicle slows down, thefield
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 partis dumped in the motor as
heat.
Section 2.1.3.c PedalPosition Plug 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 plugging
current to the "value set by this function" as the accelerator
is returned to the creep speed position. Maximum plug
current is obtained with the accelerator in the top speed
position. This featureis adjustable by using Function 16 on
the Handset.
Section 2.1.3.d Auto Braking
This featurecan be setup with the Handset using Function
17 to select "Auto Plug/Regen" . Thisfeature 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 16 ofthe Handset.
Section 2.1.3.e Brake Pedal Regenerative Braking
This feature sets or varies the amount of REGEN current
with AUTO-REGEN braking feature. The current is variable
through the use of a pot on the brake pedal to provide a
minimum AUTO-REGEN braking level at pedal up, but
increasing as the pedal is depressed. A set level of REGEN
CURRENT LIMIT is available with a set resistor on the brake
pedal. An open inputwith either adjustment modea pot or
resistor will allowcoast until either is selected. Minimum
REGEN CURRENT LIMIT requires a 4200 ohm resistor input
(minimum level 50 amp). Maximum REGEN CURRENT LIMIT
requires a 330 ohm resistor input.
Section 2.1.4 Auxiliary Speed Control
Section 2.1.4.a Field Weakening
This function allows the adjustmentof 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 isless
than 1 volt. It is important to note that this function is used
to optimizemotor and control performance, and this setting
will be determined by GE and OEM engineers at the time of
vehicle development. This setting must not be changed by
field personnel withoutthe 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", initiated
by individual limit switches. The NC switches are
connected between input points on the control card and
battery negative. The lower motor volt limit always takes
prioritywhen more than one switch inputis open. 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, for speed limits SL1, SL2, and SL3 respectively. SLl
is active in all card types and must be disabled with the
Handset if speed limits are not used.
ARM
Q1
Q2

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 8
October 1998
Section 2.1.5 Ramp Operation
Section 2.1.5a Ramp Start
This feature provides maximum control torque to restarta
vehicle on an incline. The memory for this function is the
directional switch. When stopping on an incline, the
directional switch must be leftin its original or neutral
position to allow the control to initiate full power when
restarted. Theaccelerator 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 ACCpedal 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 roll-
back speed.
Section 2.1.6 Steer Pump Contactor Time Delay
This feature provides two options for SP time delay. Option
1 provides a 0.5 to 63 second time delayed drop out of the
steer pump contactor when the Forward or Reverse
directional switch is opened. This Option 1 isoverridden by
a 1.5 second time delayed drop out whenever the seat
switch is opened. Option 2 provides a 0.5 to 63 second time
delayed drop out of the SP contactor when the seat switch
is opened.
Section 2.1.7 On-Board Coil Drivers & Internal Coil
Suppression
Coil drivers for the LINE and SP or BYPASScontactors
are on-board the control card. These contactors must have
coils rated for the vehiclebattery 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 seatswitch or key switch is opened, the
control shuts off and cannotbe restarted until the
directional lever isreturned to neutral. A time delay of
approximately 2 seconds is builtinto the seat switch input
to allow momentary opening ofthe 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 seatswitch is activated.
If, at start up, the voltage is less than 3.0 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 ifa fault conditions occurs
that would cause a disruption ofnormal 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 armatureand 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, ifeither the
armature or field FET's are defective, so as to cause
uncontrolled truck movement.
Section 2.2.4 lA Current Drop Out
This adjustable feature can be set to open the lA contactor
if the traction motor is subject to excessive currents. The
dropout is adjustable with Function 6 using the Handset.
Once the control has dropped out the lA contactor due to
excessivecurrent, the directional or accelerator switch
must be returned to neutral to reset the dropout circuit and
allow the control to pick up thelA contactor again. Using
this feature may reduce the lA contactor tip life, therefore,
it should be used only where needed to protect the motor.
Section 2.2.5 Thermal Protector (TP)
This temperature sensitive device is internal to the power
transistor (Q1) module. If the transistor's temperature
begins to exceed thedesign 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 to initiate 1A operation, thereby
allowing thecontrol to cool. As the control cools, the
thermal protector will automatically reset, returning the
control to full power.
Section 2.2.6 Low Voltage
Batteries under load, particularly if undersized or more
than 80 percent discharged, will produce low voltages at

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 9
October 1998
the control terminals. The SX control isdesigned for use
down to 50 percent ofa nominal battery voltageof 36-84
volts, and 75 percent ofa nominal battery voltageof 24
volts. Lower battery voltage may causethe control to
operate improperly, however, the resulting PMT should
open the Line contactor, in the event of a failure.
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 theDash Display or the
Handset. There arecurrently over 70 status codes thatare
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 faultcondition.
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
vehiclesso equipped, or be availableby 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 purport to
cover all possible causesof a display of a "status code ".
They do provide instructions for checking the most direct
inputs that can causestatus codes to appear.
Section 2.3.2.b Stored Status Codes
This featurerecords 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 2.3.4 Battery Discharge Indication (BDI)
The latest in microprocessor technology is used to provide
accurate battery state of chargeinformation 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 80 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 statecontrols. 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 SXcontrols.
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 thecontrol 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 servicepersonnel 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 beselected 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) Controlled
Acceleration levels, (4) Field Weakening levels and (4)
Speed Limits.
These interactive modes are "pre-set" using the Handset
(Functions 48-62)or a personal computer (Functions 97-

BASIC OPERATION AND FEATURES
SX TRANSISTOR CONTROL Page 10
October 1998
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
Coil drivers are internal to thecontrol card, and are the
power devices that operatethe Line, 1A and SPcontactor
coils. On command from the control card, these drivers
initiate opening and closing thecontactor coils. All driver
modules are equipped with reverse battery protection, such
that, ifthe battery isconnected 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 (IC3645TMM7A), or an integral function of
the GE Pump controls when used with theSX 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 wireprovides a signal to theModule.
The TMM Module can be used to display a separate status
code indicating over-temperatureof traction motors,
hydraulic motors, or any other device or system that can
activatea 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 faultcode 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 thefollowing
features:
•=Four speeds, adjustable from O to 100% motor volts.
Fixed speeds actuated by switch closure to negative.
•=P1A bypass contactor (if required)
•=Variable resistor input(5K-O ohms). Control starts
when inputis reduced to below3.5 volts.
•=PMT functions availablewhen a pump contactor is
used.
•=Current limitand controlled acceleration adjustable.
•=Battery Discharge Indicator interrupt compatible.
Operation ofvoltage regulator card: This card provides the
basic functions required for controlling thepump control,
optional contactors, and PMT functions. Battery positive is
applied through a main control fuse to the key switch,
energizing thecontrol 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 (motor volts) 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 motor voltage from O to 100%. The
specified motor volts will be regulated, however, the
magnitudeof 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 Handsetand Function
13 similar to SL1.
The fourth speed is obtained by closing SL 4 (P21) to
control negative. SL4 is adjusted using the Handset and
Function 14 similar to SL1. PIA will close 0.2 seconds after
controlled acceleration stops. Speed Limit4 (Function 14)
must be activated and set to >250 to enable the optional P 1
A contactor.
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 adjustableand
operates the same as the traction circuit. Adjustment range
is from 0.1 to 5.5 seconds.
The variable resistor input will override the fixed motor volt
limits set by the four (4) adjustable Speed Limits. It will vary
motor volts above the set limits up to full motor volts, and
closes P1A as resistance isdecreased to less than 200
ohms.
The Battery Discharge Indicator (BDI) interrupt will disable
the hydraulic controller if theconnection at P10 loses the
12 volt signal fromthe traction control. BDIinterrupt can be
disabled by Function 17 using the Handset. Select card type
with or without BDI function.