Voltage Regulator Adjustment | Generac 04758-1, 04759-1, 04760-1

Section 3 — Operation

Guardian Air-cooled 7 kW, 12 kW and 15 kW Generators

Figure 2.3 — Engine Governor Adjustment

Idle Spring

Governor

Shaft

(Rotate

Clockwise)

	Governor Clamp Bolt	No Load Idle
	Governor Clamp Bolt	Adjustment Screw
		Adjustment Screw

◆2.7.2 12 KW AND 15 KW UNITS

1.Loosen governor clamp bolt (See Figure 2.3).

2.Completely remove the idle spring.

3.With governor arm at wide open throttle position, rotate governor shaft fully clockwise. Tighten clamp bolt to 84 inch-pounds.

4.Start unit and apply full load. Use full load speed adjust screw (Figure 2.4) to adjust frequency to 58 Hz.

5.Remove load, stop engine, loosen the idle adjust screw and reconnect the idle spring.

6.Using a hand, push the governor arm to the closed throttle position. Make sure the idle spring does not stretch at all.

7.Restart the unit.

8.Slowly turn the idle adjust screw to adjust the no- load idle frequency to 63-63.5 Hz.

9.The governor is now set.

◆2.7.3 ADDITIONAL CORROSION PROTECTION

Periodically spray all engine linkage parts and brack- ets with corrosion inhibiting spray such as WD-40 or a comparable product.

2.8VOLTAGE REGULATOR

ADJUSTMENT

With the frequency between 62-63.5 Hertz, slowly turn the slotted potentiometer (Figure 2.5) until line voltage reads 244-252 volts.

NOTE:

Remove the access panel on top of the control panel to adjust the voltage regulator.

Figure 2.5 – Voltage Adjustment Potentiometer

NOTE:

The voltage regulator is housed above the genera- tor's control panel. The regulator maintains a volt- age in direct proportion to frequency. For example, at 62 Hertz, line-to-neutral voltage will be 124 volts.

Figure 2.4 — Full Load Speed Adjust Screw

Full Load Speed Adjust Screw

3.1BREAK-IN PROCEDURE

Once the unit has been installed, with utility power connected to the transfer switch, and all electrical checks have been made, it is strongly recommended that the following “Break-in Procedure” be completed to ensure correct generator operation in the future.

1.Set the generator’s AUTO/OFF/MANUAL switch to AUTO.

2.Turn OFF the utility power supply to the transfer switch using the means provided (such as a utili- ty main line circuit breaker).

3.The unit will start, and the transfer switch will transfer to standby.

4.Run the unit for one hour at 25 percent load.

5.Run the unit for one hour at 50 percent load.

6.Run the unit for one hour at 75 percent load.

7.Run the unit for one hour at 100 percent load.