GE SX TRANSISTOR CONTROL IC3645SR4U404N2 User Manual

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DIAGNOSTIC STATUS CODES  
SX TRANSISTOR CONTROL 
 
 
Page 16
 
 
 
January 2000
 
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. In dusty 
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 
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: