Kohler 11EFOZ/13EOZ, 8.5EFOZ, 9EFOZ/10EOZ manual Overvoltage adjustment potentiometer R41 LED4 red

Short circuits. Hazardous voltage/current can cause severe injury or death. Short circuits can cause bodily injury and/or equipment damage. Do not contact electrical connections with tools or jewelry while making adjustments or repairs. Remove all jewelry before servicing the equipment.

Overvoltage Shutdown Adjustment Procedure

1.Disconnect the generator set engine starting battery, negative (--) lead first. Disconnect power to the battery charger (if equipped).

2.With the generator set shut down, open the output line circuit breaker to disconnect the load from the generator set.

3.Remove the controller cover.

4.Wrap the shaft of an insulated-handle screwdriver with electrical tape to insulate the metal shaft. Turn the overvoltage potentiometer (R41) on the main circuit board fully clockwise. See Figure 8-8.

5.Connect a digital AC voltmeter (or other 1% minimum accuracy voltmeter) to terminals V0 and V7 on the controller terminal block. See Figure 8-6.

6.Reconnect the battery, negative (--) lead last.

7.Start the generator set by placing the generator set master switch in the RUN position.

8.Adjust the output voltage to 115% of the nominal output voltage using the voltage adjustment potentiometer. If the voltage configuration is 139/240 volts (low wye) or 277/480 volts (high wye), 3-phase, 4-wire, 60 Hz, adjust output voltage to 160 volts across terminals V0 and V7. For all other voltages, adjust the output to 140 volts across terminals V0 and V7.

Adjust the voltage using the voltage adjustment potentiometer on the generator controller front panel. See Figure 8-7.

9.Use the insulated screwdriver to slowly rotate the overvoltage adjustment potentiometer (R41) counterclockwise until red LED4 lights. See

Figure 8-8. The generator set should shut down on an overvoltage fault in approximately 2 seconds.

	1	2
	R41
	LED4
P2	P1
		A-336415-A

1.Overvoltage adjustment potentiometer (R41)

2.LED4 (red)

Figure 8-8 Overvoltage Shutdown Adjustment on Main Circuit Board

10.Turn the voltage adjustment potentiometer counterclockwise to prevent overvoltage shutdown upon restart. Restart the generator set. Slowly increase the voltage by turning the voltage adjustment potentiometer clockwise. Verify the shutdown voltage point (115% of the nominal output voltage) by observing the voltmeter and noting when LED4 lights. The generator set should shut down on overvoltage fault in approximately 2 seconds. If the shutdown voltage point is not 115% of nominal voltage, repeat the calibration output procedure; otherwise, continue to step 11.

11.Turn the voltage adjustment potentiometer counterclockwise to prevent overvoltage shutdown upon restart. Restart the generator set. Readjust the generator set output to the nominal voltage using the voltage adjustment potentiometer.

12.Stop the generator set by placing the generator set master switch in the OFF/RESET position. Seal the overvoltage adjustment potentiometer (R41) with RTV sealant or equivalent. Replace the controller cover.

70 Section 8 Reconnection/Adjustments TP-6069 6/03