Section 7: Control Panel/Start-up/Testing
28
Installation Guidelines For 60 Hz Air-cooled Generators
Electrical Checks
Complete electrical checks as follows:
1.
Verify that generator is OFF.
2.
Set the generator main circuit breaker to OFF or
OPEN.
3.
Turn OFF all circuit breakers/electrical loads that
will be supplied by the generator.
4.
Turn on the utility power supply to the transfer
switch using the means provided (such as a utility
main line circuit breaker).
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. If voltage is not correct,
verify AC output and wiring from utility source to N1
and N2 lugs at transfer switch.
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 (if wired
with a neutral). If voltage is not correct, verify AC
output and wiring from utility source to N1 and N2
lugs at transfer switch.
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, push the MANUAL button.
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 ON or
CLOSED.
10.
Connect an accurate AC voltmeter and a
frequency meter across transfer switch terminal
lugs E1 and E2. Voltage should be 238-242 at a
frequency of 59.5-60.5 Hz. If voltage is not correct,
verify that the MLCB is closed and verify AC output
and frequency (Hertz or Hz) at the MLCB. Also
verify wiring from generator to E1 and E2 lugs at
transfer switch.
11.
Connect the AC voltmeter test leads across
terminal lugs E1 and neutral; then across E2 and
neutral (if wired with a neutral). In both cases,
voltage reading should be 119-121 volts AC. If
voltage is not correct, verify that the MLCB is
closed and verify AC output between the E1 and
E2 of the MLCB and Neutral at the generator.
12.
Verify wiring from generator to E1, E2 and Neutral
lugs at transfer switch.
13.
Set the generator main circuit breaker to OFF or
OPEN.
14.
Push the generator OFF button. 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.
Generator Tests Under Load
To test the generator set with electrical loads applied,
proceed as follows:
1.
Verify that the generator is OFF.
2.
Turn OFF all breakers/electrical loads that will be
powered by the generator.
3.
Turn OFF the utility power supply to the transfer
switch, using the means provided (such as a utility
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.
Push the generator MANUAL button. The engine
should crank and start immediately.
6.
Let the engine stabilize and warm up for a few
minutes.
7.
Set the generator main circuit breaker to ON or
CLOSED. Loads are now powered by the standby
generator.
8.
Turn ON the circuit breaker/electrical loads that are
powered by the generator one by one.
9.
Connect a calibrated AC voltmeter and a frequency
meter across terminal lugs E1 and E2. Voltage
should be approximately 240 volts and frequency
should be 60 Hz. If the voltage and frequency are
rapidly dropping as the loads are applied, the
generator may be overloading or there may be a
fuel issue. Check amperage value of loads and/or
fuel pressure.
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.
Verify gas pressure while under full load.
(000129)
DANGER
Electrocution. High voltage is present at
transfer switch and terminals. Contact with live
terminals will result in death or serious injury.
(000132)
DANGER
Electrocution. Do not manually transfer under load.
Disconnect transfer switch from all power sources
prior to manual transfer. Failure to do so will result
in death or serious injury, and equipment damage.
