GE Industrial Solutions ZTSH SERIES 30-4000 AMPS - Manual (Page 8)

■ ■ 6 Zenith Controls, Inc. ■ ■ ZTSH Operation and Maintenance Manual (43R-1000)
Next, close the Emergency source breaker and start the engine generator. The VFSM relay
will pick up and the LED indicator will be illuminated. Check the phase to phase voltages at
the Emergency line terminals. Also, verify that the phase rotation of the Emergency source is
the same as the phase rotation of the Normal source.
After the sources have been verified, shut down the engine generator, and put the starting
control in the automatic position. Complete the visual inspection of the transfer switch,
and close and lock the cabinet door.
Initiate the electrical transfer test by activating the TS test switch. The CR control relay will
drop out and the P1 engine start timer will start its timing cycle.
After the P1 timer has completed its timing cycle, the engine start contact will close and signal
the engine generator to start. The VFSM relay will energize. The switch will transfer to the
Emergency source after the time delay of the W timer.
Deactivating the test switch will start retransfer to the Normal source. The switch will retrans-
fer to the Normal source after the time delay of the T timer. The U engine over-run timer allows
the engine generator to run unloaded for a preset cool down time period.
Installation
(cont’d)
NOTICE
A periodic test of the transfer switch under load conditions is recommended to insure proper operation.
(See National Electric Code articles 700 and 701).