Section 2 — Post Installation Start-up and Adjustments

Air-cooled Generators

2.1BEFORE INITIAL START-UP

NOTE:

These units have been run and tested at the fac- tory prior to being shipped and do not require any type of break-in.

Before starting, complete the following:

1.Set the generator’s main circuit breaker to its OFF (or OPEN) position.

2.Set the generator's AUTO/OFF/MANUAL switch to the OFF position.

3.Turn OFF all breakers on the load center of the transfer box (T1 and T2).

4.Turn OFF all loads connected to the transfer switch terminals T1 and T2.

5.Check the engine crankcase oil level and, if neces- sary, fill to the dipstick FULL mark with the rec- ommended oil. Do not fill above the FULL mark.

6.Check the fuel supply. Gaseous fuel lines must have been properly purged and leak tested in accordance with applicable fuel-gas codes. All fuel shutoff valves in the fuel supply lines must be open.

DANGER

The transfer switch is now electrically “hot.” Contact with “hot” parts will result in extremely hazardous and possibly fatal electrical shock. Proceed with caution.

5.Use an accurate AC voltmeter to check utility power source voltage across transfer switch ter- minals N1 and N2. Nominal line-to-line voltage should be 240 volts AC.

6.Check utility power source voltage across termi- nals N1 and the transfer switch neutral lug; then across terminal N2 and neutral. Nominal line-to- neutral voltage should be 120 volts AC.

7.When certain that utility supply voltage is compat- ible with transfer switch and load circuit ratings, turn OFF the utility power supply to the transfer switch.

8.On the generator panel, set the AUTO/OFF/ MANUAL switch to MANUAL. The engine should crank and start.

9.Let the engine warm up for about five minutes to allow internal temperatures to stabilize. Then, set the generator’s main circuit breaker to its ON (or CLOSED) position.

Never operate the engine with the oil level below the “Add” mark on the dipstick. Doing this could damage the engine.

2.2CHECK TRANSFER SWITCH

OPERATION

Refer to the "Manual Transfer Operation" section, of the owner’s manual for procedures.

DANGER

Do not attempt manual transfer switch opera- tion until all power voltage supplies to the transfer switch have been positively turned off. Failure to turn off all power voltage supplies will result in extremely hazardous and possibly fatal electrical shock.

2.3ELECTRICAL CHECKS

Complete electrical checks as follows:

1.Set the generator's main circuit breaker to its OFF (or OPEN) position.

2.Set the generator's AUTO/OFF/MANUAL switch to the OFF position.

3.Turn OFF all breakers on the load center of the transfer box (T1 and T2).

4.Turn on the utility power supply to the transfer switch using the means provided (such as a utility main line circuit breaker).

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DANGER

Proceed with caution! Generator power voltage is now supplied to the transfer switch. Contact with live transfer switch parts will result in dan- gerous and possibly fatal electrical shock.

10.Connect an accurate AC voltmeter and a frequen- cy meter across transfer switch terminal lugs E1 and E2. 7kW voltage should be 242-252 volts at a frequency of 61-63 Hertz. 10, 13, and 16kW voltage should be 250-252 volts at a frequency of 57.5-59.5 Hertz.

11.Connect the AC voltmeter test leads across ter- minal lugs E1 and neutral; then across E2 and neutral. In both cases, voltage reading should be 121-126 volts AC (7kW), and 125-126 volts AC (10, 13 and 16kW).

12.Set the generator’s main circuit breaker to its OFF (or OPEN) position. Let the engine run at no- load for a few minutes to stabilize internal engine generator temperatures.

13.Set the generator's AUTO/OFF/MANUAL switch to OFF. The engine should shut down.

NOTE:

It is important not to proceed until certain that generator AC voltage and frequency are correct and within the stated limits. Generally, if both AC frequency and voltage are high or low, the engine governor requires adjustment* (*GH410 only). If frequency is correct, but voltage is high or low, the generator’s voltage regulator requires adjustment.

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Generac Power Systems 5253, 5252, 5254, 5251 Before Initial START-UP, Check Transfer Switch Operation, Electrical Checks