GE SX Series Installation And Operation Manual

GE SX Series Installation And Operation Manual Manual pdf 16 page image

DIAGNOSTIC STATUS CODESSX TRANSISTOR CONTROL Page 16Revised May 2003Section 4.0 TROUBLESHOOTING AND DIAGNOSTIC STATUS CODESSection 4.1 General Maintenance InstructionsThe transistor control, like all electrical apparatus, doeshave some thermal losses. The semiconductor junctionshave finite temperature limits, above which these devicesmay be damaged. For these reasons, normal maintenanceshould guard against any action which will expose thecomponents to excessive heat and/or those conditionswhich 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 temperaturesover 100° F (40° C) should be brought to the attention of thevehicle manufacturer.All external components having inductive coils must befiltered. Refer to vehicle manufacturer for specifications.The wiring should not be directly steam cleaned. In dustyareas, blow low-pressure air over the control to removedust. In oily or greasy areas, a mild solution of detergent ordenatured alcohol can be used to wash the control, andthen low-pressure air should be used to completely dry thecontrol.For the control to be most effective, it must be mountedagainst the frame of the vehicle. The metal vehicle frame,acting as an additional heat sink, will give improved vehicleperformance by keeping the control package cooler. Applya thin layer of heat-transfer grease (such as Dow Corning340) between the control heat sink and the vehicle frame.Control wire plugs and other exposed transistor controlparts should be kept free of dirt and paint that mightchange the effective resistance between points.CAUTION: The vehicle should not be plugged when thevehicle is jacked up and the drive wheels are in a freewheeling position. The higher motor speeds can createexcessive voltages that can be harmful to the control.Do not hipot (or megger) the control. Refer to controlmanufacturer before hipotting.Use a lead-acid battery with the voltage and ampere hourrating specified for the vehicle. Follow normal batterymaintenance procedures, recharging before 80 percentdischarged with periodic equalizing charges.Visual inspection of GE contactors contained in the tractionand pump systems is recommended to occur during every160 hours of vehicle operation. Inspection is recommendedto verify that the contactors are not binding and that thetips are intact and free of contaminants.GE does not recommend that any type of welding beperformed on the vehicle after the installation of thecontrol(s) in the vehicle. GE will not honor control failuresduring the warranty period when such failures areattributed to welding while the control is installed in thevehicle.Section 4.2 Cable Routing and SeparationElectrical noise from cabling of various voltage levels caninterfere with a microprocessor-based control system. Toreduce this interference, GE recommends specific cableseparation and routing practices, consistent with industrystandards.Section 4.2.1 Application ResponsibilityThe customer and customer’s representative areresponsible for the mechanical and environmentallocations of cables. They are also responsible for applyingthe level rules and cabling practices defined in this section.To help ensure a lower cost, noise-free installation, GErecommends early planning of cable routing that complieswith these level separation rules.On new installations, sufficient space should be allowed toefficiently arrange mechanical and electrical equipment.On vehicle retrofits, level rules should be considered duringthe planning stages to help ensure correct application anda more trouble-free installation.Section 4.2.2. Signal/Power Level DefinitionsThe signal/power carrying cables are categorized into fourdefining levels: low, high, medium power, and high power.Within those levels, signals can be further divided intoclasses.Sections 4.2.2.a through 4.2.2.d define these levels andclasses, with specific examples of each. Section 4.2.3contains recommendations for separating the levels.4.2.2.a Low-Level Signals (Level L)Low-level signals are designated as level L. These consistof: 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 mAThe following are specific examples of level L signals usedin drive equipment cabling: