Generac 005031-2 3.9VOLTAGE REGULATOR ADJUSTMENT, ‹Every Three Months, ‹Once Every Six Months

Section 4 — Maintenance

Switch Position 8 — Selects whether the control is in the Normal Mode of operation or Test Mode. In the Normal Mode of operation, pre-determined governor gains are used and the gain trimpots on the control board (Gain, Stability, and Differential) are not active and have no effect on the gains. In Test Mode the gain trimpots are active and can be adjusted. See Section 3.4.

3.9VOLTAGE REGULATOR

ADJUSTMENT

Four adjustment potentiometers are provided on the voltage regulator installed in the control panel (Figure 3.4). These are (a) voltage adjust, (b) gain, (c) stability and (d) underfrequency adjust. The voltage regulator potentiometers have been factory set and SHOULD NOT be adjusted. If however, adjustments are necessary, contact the local Dealer to implement the following procedure.

High voltage is present inside the control panel during this procedure.

1.Disconnect all electrical loads from the generator (initial adjustments are done under no-load con- ditions).

Figure 3.4 — Voltage Regulator

2.Connect an accurate AC voltmeter and AC fre- quency meter to the generator’s AC output leads.

3.On the voltage regulator, set the potentiometers as follows:

Liquid-cooled 25 kW Generators

5.Verify that the three voltage regulator’s LED’s are ON.

6.Check the reading on the AC frequency meter.

7.Turn the voltage regulator’s VOLTAGE ADJUST pot to obtain a line-to-line voltage of:

A.240 VAC if the generator has been configured for

60 Hertz operation.

B.200 VAC if the generator has been configured for

50 Hertz operation.

8.If the RED REGULATOR LED is flashing, adjust the STABILITY pot in either direction until the flashing stops.

9.Apply an electrical load and check the engine speed recovery.

A.Adjust the UNDERFREQUENCY ADJUST pot CCW to reduce load during engine recovery.

B.For flat regulation (no voltage decrease as fre- quency drops) set the UNDERFREQUENCY ADJUST pot fully CW.

C.To obtain a constant voltage regulation as fre- quency decreases, set the UNDERFREQUENCY ADJUST pot fully CCW.

10.With the electrical load still applied, check the REGULATOR LED for flashing. If the LED is flashing, adjust the STABILITY pot until the flash- ing stops.

11.If better response is needed, adjust the GAIN pot clockwise (CW) as needed. Then (if needed) cor- rect for stability by adjusting the STABILITY pot.

12.Turn OFF the electrical loads.

13.Verify that all the voltage regulator’s LED’s are ON.

14.Turn OFF the generator.

4.1MAINTENANCE PERFORMED BY AUTHORIZED SERVICE FACILITIES

‹EVERY THREE MONTHS

1.Check battery condition.

2.Inspect and test fuel system.

3.Check transfer switch.

4.Inspect exhaust system.

5.Check engine ignition system.

6.Check fan belts.

A. Turn the Voltage Adjust pot fully counterclock- wise (CCW).

B. Set the GAIN pot to its centered (mid) position. C. Set the STABILITY pot to its centered (mid)

position.

D. DO NOT adjust the UNDERFREQUENCY ADJUST pot.

4.Start the engine. Let it stabilize and warm up at no-load.

‹ONCE EVERY SIX MONTHS

1.Test Engine Safety Devices (low oil pressure, low coolant level, high coolant temperature).

‹ONCE ANNUALLY

1.Test engine governor; adjust or repair, if needed.

2.Clean, inspect generator.

3.Flush cooling system.

17