GE SPM Series Instruction Manual

Also see for SPM: Instruction manual

Contents

2- 6SPM Synchronous Motor Protection & Control GE Power Management2.3 ELECTRICAL INSTALLATION 2 INSTALLATION22.3.2 GROUNDINGThe SPM relay must be solidly grounded to a suitable system ground. Extensive filtering and transient protec-tion has been built into the SPM to ensure proper and reliable operation in harsh industrial environments.Proper grounding of the chassis ground terminal is critical to en-sure safety and filtering.2.3.3 FIELD AND EXCITER VOLTAGE INPUTSThe field voltage inputs (VF + and V F –) and exciter voltage inputs (V E + and VE –) are connected to the relayvia the supplied voltage divider network (VDN).DO NOT ATTEMPT TO START THE MOTOR WITHOUT THE EXTERNAL RESISTOR ASSEMBLYWIRED. SEVERE DAMAGE TO THE SPM MAY RESULT IF THE EXTERNAL RESISTOR ASSEM-BLY IS NOT PROPERLY CONNECTED.2.3.4 RELAY OUTPUTSThe following is a description of the relay outputs.1. TRIP: Trip Relay. This relay is normally energized and drops out on loss of power or when the modulesenses an abnormal condition.2. FAR: Field Application Relay. This relay picks up at the proper time to apply DC to the motor field.3. FCX: Loading Relay. This relay picks up when the motor is fully synchronized and ready to be loaded. It iscontrolled by the "FCX Delay" programmable setpoint.2.3.5 CURRENT TRANSFORMER INPUTThe SPM is designed to work from a five ampere (5 A) current transformer (CT) secondary. The current trans-former must be connected in the proper motor phase. See Figure 2–3: TYPICAL WIRING DIAGRAM on page2–4 to determine proper phase. For brushless applications, the SPM requires inputs from two motor phases.2.3.6 POWER FACTOR OUTPUTThis output is a 0 to 10 V DC signal that corresponds linearly to phase shift, and sinusoidal to motor power fac-tor. 0 V is zero lagging power factor, 5 V is unity power factor, and 10 V is zero leading power factor.Calibration: 1 volt change corresponds to an 18° phase shift (not available with power factor regulation). Do notconnect less than 1000 Ω to this output.2.3.7 DC FIELD CURRENT INPUTDC field input must be sensed from a separately purchased DCCT (Direct Current, Current Transformer) andCM (Calibration Module).2.3.8 EXCITER VOLTAGE OUTPUT MONITORThe output of the field exciter must be connected to the SPM through a separate resistor when exciter voltagefailure protection and/or exciter voltage display is required.CAUTION