COVER AS 3578807 - Caterpillar

OP10 is the option for adjusting the voltmeter readings of the GSC. This adjustment may be necessary when generator sets are operated in parallel. The GSC AC voltage measurements are calibrated at the factory. An accurate standard is used. However, when two generator sets are paralleled, the application may require the paralleled generator sets to have exactly the same voltage value. The AC offset of one GSC is changed to match the voltage value of another generator set. Note: It is NOT recommended that the AC offset be altered under any other circumstances. Performing this procedure takes the GSC out of factory calibration. Procedure For Voltmeter Offset Adjustment
The paralleled generator sets must be running at rated speed. The generator sets can then have the voltage adjustment made. Note: Service mode cannot be entered when the ECS is in the AUTO position.
Enter service mode on the GSC that is being adjusted. Enter the password. "OP 1" is showing on lower display. For more information, see the Service Manual, "Service Mode". For more information, see the Service Manual, "Password Entry OP3".
Press "SCROLL UP" key nine times. "OP 10" is showing on the lower display.
Press "SELECT" key. "AC CAL" is showing on lower display. The present A-B voltage value is showing on the upper display.
Press "SELECT" key. The voltage value is flashing.
Press the "SCROLL UP" key or press the "SCROLL DOWN" key in order to adjust the voltage. Adjust the value to exactly match the other generator set(s) that are running in parallel. Voltage value continues to flash.
Press "ENTER" key. The value of the setpoint stops flashing.
Press "SCROLL UP" key. Repeat steps 3, 4, 5 and 6 for the B-C voltage and the C-A voltage.
Press "EXIT" key. "OP 1" is showing on the lower display.
Press "EXIT" key. The display returns to the normal state.