Guardian Technologies 4759, 4456, 4390, 4389, 4760 Generator Tests Under Load, Section, Danger, Part

OPERATIONAL TESTS AND ADJUSTMENTS

PART 5

SECTION 5.1

SYSTEM FUNCTIONAL TESTS

2.Set the generator AUTO-OFF-MANUAL switch to the “OFF “ position.

3.Turn off all loads connected to the transfer switch terminals 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).

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 terminals N1 and N2. Nominal line-to-line voltage should be 240 volts AC.

6.Check utility power source voltage across terminals 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 compatible 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 main circuit breaker to its “ON” (or closed) position.

DANGER

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

10.Connect an accurate AC voltmeter and a frequency meter across transfer switch terminal lugs E1 and E2. Voltage should be 242-252 volts; frequency should read about 61-63 Hertz.

11.Connect the AC voltmeter test leads across terminal lug E1 and neutral; then across E2 and neutral. In both cases, voltage reading should be 121-126 volts AC.

12. Set the generator 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 AUTO-OFF-MANUAL switch to OFF. The engine should shut down.

NOTE: It is important that you do not proceed until you are 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. If frequency is correct, but voltage is high or low, the generator voltage regulator requires adjustment.

GENERATOR TESTS UNDER LOAD

To test the generator set with electrical loads applied, proceed as follows:

1.Set generator main circuit breaker to its OFF (or open) position.

2.Turn OFF all loads connected to the Transfer Switch Terminals T1 and T2.

3.Set the generator AUTO-OFF-MANUAL switch to OFF.

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

Do not attempt manual transfer switch operation 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.

5.Manually set the transfer switch to the STANDBY position, i.e., load terminals connected to the generator E1/E2 terminals. The transfer switch operating lever should be down.

6.Set the generator AUTO-OFF-MANUAL switch to MANUAL. The engine should crank and start immediately.

7.Let the engine stabilize and warm up for a few minutes.

8.Set the generator main circuit breaker to its ON (or closed) position. Loads are now powered by the standby generator.

9.Turn ON electrical loads connected to transfer switch T1

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