Generac 004912-0, 004912-1, 004913-0, 004913-1, 004913-2 Using a Standard GTS Transfer Switch

Section 3 - Operation

Centurion Liquid-cooled 15 kW and 25 kW Generators

3.1USING A STANDARD “GTS”

TRANSFER SWITCH

When required, the pre-packaged standby generator can be installed with an engineered Generac “GTS” type engineered automatic transfer switch.

When a GTS type transfer switch is used, it controls automatic operation and automatic transfer as follows:

•Solid state circuits in the transfer switch monitor utility power source voltage.

•When utility source voltage drops below a pre-set level, transfer switch action closes the circuit. The engine then cranks and starts as controlled by the pre-packaged generator’s Control Module circuit board.

•After the engine starts and when the generator AC output voltage and frequency have reached a pre-set value, transfer switch circuits signal the transfer switch main contacts to actuate to the “Standby” power source side. Generator AC output then powers load circuits.

•When the utility power source voltage is restored above a pre-set level, transfer switch solid state circuits signal the switch main contacts to move back to their utility power source side.

•Following re-transfer back to the utility power source side, transfer switch circuit board action opens the circuit. Engine then shuts down.

NOTE:

If the generator is installed in conjunction with an engineered GTS type engineered transfer switch, refer to the applicable transfer switch manual for exact operating parameters and timing sequences.

‹3.2.1 HOURMETER

Indicates time the generator has operated, in hours and tenths of hours. Use the hourmeter along with the periodic maintenance schedule for the generator set.

‹3.2.2 AUTO/OFF/MANUAL SWITCH

Use this three-position switch as follows:

•Set the switch to AUTO for fully automatic operation. See Section 3.4, “Automatic Operation”.

•Set switch to MANUAL position to crank and start the generator engine.

•Set switch to OFF position to shut down an operating engine. With OFF selected, operation will not be possible.

DANGER

With switch set to AUTO, engine can crank

!and start suddenly without warning. Such automatic start up normally occurs when utility source voltage drops below a pre-set level. To prevent possible injury that might be caused by such sudden starts, set the AUTO/OFF/MANUAL switch to OFF before working on or around the unit. Then, place a "DO NOT OPERATE" tag on control console.

‹3.2.3 FAULT INDICATOR LAMP

The lamp goes ON when one or more of the following engine faults occurs and when engine shuts down.

• Low oil pressure	•	Overcrank
• High coolant temperature	•	Overspeed
• Low coolant level

3.2CONTROL CONSOLE

COMPONENTS

The components of a liquid-cooled generator control console (Figure 3.1) are as follows:

Figure 3.1 - Liquid-Cooled Generator Panel

	FUSE	FAULT
HOUR METER	15-A	INDICATOR
	AGC
AUTO
		SET
OFF		EXERCISE
		TIME
		ON
MANUAL

‹3.2.4 15 AMP FUSE

The fuse protects the control console’s DC control circuit against electrical overload. If the fuse has melted open due to an overload, or is removed, engine cranking and startup may still occur when the AUTO/OFF/MANUAL switch is placed in the AUTO or MANUAL positions.

NOTE:

To disable the control board and thus prevent potential crank and run, the 15 amp fuse AND the

7.5amp in-line fuse must both be removed or the battery cables should be disconnected.

Should you need to replace the fuse, use only an identical AGC 15-amp replacement fuse.

Generac® Power Systems, Inc. 13