Generac Power Systems Nexus smart, Technical Manual

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Generac® Power Systems, Inc. 7
3.3.2 GENERATOR VOLTAGE CHECKS
1. On the generator panel, set the AUTO/OFF/MANUAL switch to
MANUAL position. The generator should crank and start.
2. Let the generator stabilize and warm up at no-load for at least
five minutes.
3. Set the generator's main circuit breaker (CB1) to its ON or
CLOSED position.
 
PROCEED WITH CAUTION. GENERATOR
OUTPUT VOLTAGE IS NOW BEING DELIVERED
TO TRANSFER SWITCH TERMINALS.
CONTACT WITH LIVE TERMINALS RESULTS
IN EXTREMELY DANGEROUS AND POSSIBLY
FATAL ELECTRICAL SHOCK.
4. With an accurate AC voltmeter and frequency meter, check the
no-load, voltage and frequency.
Measure across ATS terminal lugs E1 to E2; E1 to NEUTRAL
and E2 to NEUTRAL.
a. Frequency ..........................................60-62 Hz
b. Terminals E1 to E2 .............................240-246 VAC
c. Terminals E1 to NEUTRAL ..................120-123 VAC
d. Terminals E2 to NEUTRAL ..................120-123 VAC

Failure to do so may result in damage to cer-
tain rotary equipment.
5. When certain that UTILITY supply voltage is correct and
compatible with transfer switch ratings, turn OFF the UTILITY
supply to the transfer switch.
6. Set the generator’s main circuit breaker (CB1) to its OFF or
OPEN position.
7. Set the Auto/Off/Manual switch to the OFF position to shut
down the generator.
NOTE:
Do NOT proceed until generator AC output voltage and frequen-
cy are correct and within stated limits. If the no-load voltage is
correct but no-load frequency is incorrect, the engine governed
speed probably requires adjustment. If no-load frequency is
correct but voltage is not, the voltage regulator may require
adjustment.
7
Attach handle to actuating shaft.
Move handle
UP for the
NORMAL
(UTILITY)
position.
Move handle
DOWN for the
EMERGENCY
(STANDBY)
position.
NOTE: Return handle to
storage position in enclosure
when finished with manual transfer.
Figure 3.1 — Actuating Transfer Switch
Operation