INSTALLATION
(continued)
Voltage Checks
First check nameplate on the transfer switch for rated
voltage. It should be the same as the normal and emer
gency line voltages ..
CAUTION: Verify that the feeders have been
connected to the proper lugs.
ADANGER:
Use extreme caution when us
ing a meter to measure voltages in the follow
ing steps. Do not touch power terminals;
shock, burns, or death could result.
1.
Close the normal source circuit breaker. The
LOAD
CONNECTED TO NORMAL
lamps should light.
2. Use an accurate voltmeter to check phase to phase
and phase to neutral voltages present at the Transfer
Switch normal source terminals.
3. Close the emergency source circuit breaker. (Start
the generator, if necessary.) The
EMERGENCY
AVAILABLE
lamp should light.
4.
Use an accurate voltmeter to check phase to phase
and phase to neutral voltages present at the Transfer
Switch emergency source terminals.
If
necessary, adjust the voltage regulator on the generator
according to the manufacturer's recommendations. The
Automatic Transfer Switch will respond only to the rated
voltage specified on the nameplate.
5. Check phase rotation; it must be the same as the nor
mal source.
6.
Shut down the engine-driven generator. Then put
the starting control selector switch (on the generator
set) in the
automatic
position.
7. Close the cabinet door and tighten the screws.
Electrical Operation
This procedure will check the electrical operation of the
Automatic Transfer Switch. Put engine starting control in
automatic
position.
WARNING:
Close the cabinet door first.
Transfer Test
Both normal and emergency sources must be available.
1. Operate and hold the door-mounted Transfer Test
switch until the engine starts and runs. This should
happen within 15 seconds.
2. The transfer switch will operate to the Emergency po.
sition.
If
Feature 2B is used, the transfer will occur
after a time delay (up to 8 minutes). The
L OAD
CONNECTED TO EMERGENCY
light should come
on; the
LOAD CONNECTED TO NORMAL
light
should go off.
3. The transfer switch will operate back to the Normal
position after Feature 3A time delay (up to 30 min
utes). The
LOAD CONNECTED T O NORMAL
light
should come on; the
LOAD CONNECTED TO
EMERGENCY
light should go off.
4.
Feature 2E allows the engine to run unloaded for a
cool-down period (up to 30 minutes).
This completes the Functional Test of the ASCO 940. The
engine-driven generator's starting control should be left
in the
automatic
position.
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