Generac Power Systems 05176-0 - Manual (Page 13)

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3. 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.
4. 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.
5. Set the generator's main circuit breaker to its
OFF (or OPEN) position. Initial tests will be con-
ducted at no-load condition.
6. On the generator panel, set the AUTO/OFF/
MANUAL switch to MANUAL. The engine should
crank and start.
7. 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.
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.
8. Connect an accurate AC voltmeter and a fre-
quency meter across transfer switch terminal
lugs E1 and E2. Voltage should be 242-252 volts;
frequency should read about 61-63 Hertz.
9. Connect the AC voltmeter test leads across ter-
minal lug E1 and neutral; then across E2 and
neutral. In both cases, voltage reading should be
121-126 volts AC.
10. 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.
11. 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. If frequency is cor-
rect, but voltage is high or low, the generator’s
voltage regulator requires adjustment.
3.4 GENERATOR TESTS UNDER LOAD

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.
To test the generator set with electrical loads applied,
proceed as follows:
1. Set generator’s main circuit breaker to its OFF
(or OPEN) position.
2. Set the generator's AUTO/OFF/MANUAL
switch to OFF.
3. Turn OFF the utility power supply to the transfer
switch, using the means provided (such as a util-
ity main line circuit breaker).
4. 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.
5. Set the generator's AUTO/OFF/MANUAL switch
to MANUAL. The engine should crank and start
immediately.
6. Let the engine stabilize and warm up for a few
minutes.
7. Set the generator’s main circuit breaker to its ON
(or closed) position. Loads are now powered by
the standby generator.
8. Turn ON electrical loads. Apply an electrical load
equal to the full rated wattage/amperage capacity
of the installed generator.
9. Connect an accurate AC voltmeter and a frequen-
cy meter across terminal lugs E1 and E2. Voltage
should be greater than 230 volts; frequency
should be greater than 58 Hertz.
10. 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 overheating, etc.
11. When testing under load is complete, turn OFF
electrical loads.
12. Set the generator's main circuit breakers to their
OFF (or open) positions.
13. Let the engine run at no-load for a few minutes.
14. Set the AUTO/OFF/MANUAL switch to OFF. The
engine should shut down.
Section 3 — Post Installation Start-up and Adjustments
Air-cooled 15 kW Generators