Generator Tests Under Load - Generac Power Systems 8 kW Owner's Manual

10. Connect an accurate AC voltmeter and a frequency meter
across transfer switch terminal lugs E1 and E2. 8kW voltage
should be 230-240 volts at a frequency of 61-63 Hertz. 14,
17 and 20kW voltage should be 247-249 at a frequency of
59.5-60.5 Hertz. 10kW voltage should be 220-230 volts at a
frequency of 59.5-60.5 Hertz.
11. Connect the AC voltmeter test leads across terminal lugs E1
and neutral; then across E2 and neutral. In both cases, volt-
age reading should be 121-126 volts AC (8kW), and 125-126
volts AC (10, 14, 17 and 20kW).
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.
It is important not to proceed until certain that gener-
ator 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.
2.3

GENERATOR TESTS UNDER LOAD

To test the generator set with electrical loads applied, proceed as
follows:
1. Set generator's main circuit breaker to its OFF (or OPEN) posi-
tion.
2. Turn OFF all loads connected to the transfer switch terminals
T1 and T2.
3. Set the generator's 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 electri-
cal shock.
5. Manually set the transfer switch to the STANDBY position, i.e.,
load terminals connected to the generator's E1/E2 terminals.
The transfer switch operating lever should be down.
6. Set the generator's 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's main circuit breaker to its ON (or CLOSED)
position. Loads are now powered by the standby generator.
9. Turn ON the load center fed by the transfer switch (T1 and
T2).
Section 2 — Post Installation Start-up and Adjustments
NOTE:
Air-cooled Generators
10. Connect an accurate AC voltmeter and a frequency meter
across terminal lugs E1 and E2.
• 8kW voltage should be greater than 230 volts and frequency
should be greater than 58 Hz.
• 10, 14, 17 and 20kW voltage should be greater than 240 volts
and frequency should be 60 Hz.
11. Let the generator run at full rated load for 20-30 minutes.
Listen for unusual noises, vibration or other indications of
abnormal operation. Check for oil leaks, evidence of overheat-
ing, etc.
12. When testing under load is complete, turn OFF electrical
loads.
13. Set the generator's main circuit breaker to its OFF (or OPEN)
position.
14. Let the engine run at no-load for a few minutes.
15. Set the AUTO/OFF/MANUAL switch to OFF. The engine should
shut down.
2.4 CHECKING AUTOMATIC OPERATION
To check the system for proper automatic operation, proceed as
follows:
1. Set generator's main circuit breaker to its OFF (or OPEN) posi-
tion.
2. Check that the AUTO/OFF/MANUAL switch is set to OFF.
3. Turn OFF the utility power supply to the transfer switch, using
means provided (such as a utility main line circuit breaker).
4. Manually set the transfer switch to the UTILITY position, i.e.,
load terminals connected to the utility power source side.
5. Turn ON the utility power supply to the transfer switch,
using the means provided (such as a utility main line circuit
breaker).
6. Set the generator's main circuit breaker to its ON (or CLOSED)
position.
7. Set the AUTO/OFF/MANUAL switch to AUTO. The system is
now ready for automatic operation.
8. Turn OFF the utility power supply to the transfer switch.
With the AUTO/OFF/MANUAL switch at AUTO, the engine should
crank and start when the utility source power is turned OFF after a
10 second delay. After starting, the transfer switch should connect
load circuits to the standby side after a 20 to 50 second selectable
delay. Let the system go through its entire automatic sequence of
operation.
With the generator running and loads powered by generator AC
output, turn ON the utility power supply to the transfer switch. The
following should occur:
• After about 10 seconds, the switch should transfer loads back
to the utility power source.
• About one minute after re-transfer, the engine should shut
down.
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