Feature Article
EV100/200 LX/LXT Handset
System Analyzers have come a long way from the original GE C185 and M210 switch type boxes. Along with major improvements in vehicle control systems has also come significant advancements in the instruments used to help us troubleshoot failures. If you are involved with servicing the General Electric EV-100/200LX/LXT systems you will need the exclusive Handset.
The EV100LX Handset is a multi-functional service aid to be used with the EV100/200LX and LXT SCR control systems. The handset consists of a four digit display, an eighteen button keypad, an adjustment potentiometer and a telephone type cord for connections to the "Y" plug on the control card. When servicing one of these systems the first thing you will notice is the additional "Y" plug cavity located on the control card-yes, right where all those adjustment potentiometers are supposed to be! You have just encountered your first requirement for the Handset: adjustment. The Handset is used to accurately setup all parameters of the system from creep speed to 1A dropout current, if supplied by the control card type. The Handset taps into the control card micro-processor for all set up adjustments. Once the control card is setup the adjustments are stable, without drift, and are tamper proof (without a Handset and the knowledge to use one). Seventeen function codes are set aside for all the various traction control card adjustments and nine function codes for the pump controller. Each one of these function codes will adjust a specific parameter of the control card, including an adjustment for vehicle battery voltage, which is required for the controls equipped with the battery discharge indicator.
Although all the adjustment setting may cause minor mis-operations, if out of adjustment, the "Card Selection Type" will actually cause some functions to fail completely.
The "Card Selection Type" may be called the actual finger print setting of the control card. This means that a typical EV100 TT control card, even though identical on the outside, may be setup completely different on the inside. Using the "Card Selection Type" function we can program a standard EV100 TT control card different ways. A "TT" card can be set for standard or high current operation and it may be programmed with or without auto plugging. Further still you have a choice of having speed limit, field weakening or both field weakening and regenerative braking. Of course, your vehicle must match the application which you program into the control card.
The other major use for the handset is fault detection and diagnosis. Status codes are read on the four digit display and will help the service technician troubleshoot numberous possible failures. The control card continuosly monitors the complete system for failures, once a failure condition exists the control card stores certain status codes in memory to be accessed by the Handset. Once the handset is plugged into the "Y" connector, a status code (or fault code) can be displayed on the four digit display. Accessing the status code will now take you to the status code instructions where you will be guided through information and troubleshooting steps to diagnose that particular failure. Each status code diagram shown in the instruction manual will give you a description, symptom and possible causes for each failure. Nothing yet is going to do the repairs for you or pick up all types of failures, but the Handset is a pleasant start to a new future.
