NUT 8T4131 - Caterpillar

System Operation Description:The EMCP 4 detects an overcurrent condition that persists for a duration that is a function of the overcurrent level or a condition that exceeds a threshold for a programmed duration. If the RMS current of any phase goes above the "Generator Definite Time Over Current (Amp) Percentage" threshold, then a timer is started and the generator over current event is made active.The tripping time for generator overcurrent detection is determined from the phase with the highest current, and is the smaller of two values: the curve time and the generator definite time over current (Amp) "shutdown event notification delay time" (setpoint value). If an overcurrent condition is detected, then "GEN OVER CURRENT SHUTDOWN" or "GEN OVERCURRENT " will be displayed on the EMCP 4. This warning is used to inform the operator of an overcurrent condition.Note: The severity of the overcurrent condition will determine if a warning or shutdown event occurs.Conditions Which Generate This Code:The code for generator overcurrent is generated when the EMCP 4 determines that a generator overcurrent condition has occurred.Test Step 1. TALK TO THE OPERATOR
Determine the conditions that caused the overcurrent condition. Expected Result:An overcurrent was caused by an occurrence known to the operator. The operator would like to place the generator set back into service.Results:
OK - The operator can determine the cause for the overcurrent condition. The condition has been repaired, and the operator wants to place the generator set back into service.Repair: Reset the generator set. Resume normal operation and verify that the problem has been corrected.The generator set operates normally.
NOT OK - The overcurrent condition was not caused by an occurrence known to the operator. Proceed to Test Step 2Test Step 2. CHECK THE SETPOINTS.
View the setpoints: "Generator Current Transformer Primary Winding Rating", "Generator Current Transformer Secondary Winding Rating", and all of the overcurrent setpoints. Make a note of the setpoints. Refer to Testing and Adjusting, "Electronic Control Module (Generator Set) - Configure". Compare the setpoints against the default setpoints of the particular generator set. Expected Result:The setpoints are correct.Results:
OK - The setpoints are correct for your particular generator set.Repair: Reset the generator set. Resume normal operation and verify that the problem has been corrected.STOP
NOT OK - The setpoints are NOT correct.Repair: Reprogram the setpoints. Reset the generator set. Resume normal operation and verify that the problem has been corrected.STOP