Product Manual

TP-6946 3/16 53Section 6 Operation
Servicing the transfer switch. Hazardous voltage can
cause severe injury or death. Deenergize all power sources
before servicing. Turn off the main circuit breakers of all
transfer switch power sources and disable all generator sets
as follows: (1) Move all generator set master controller
switches to the OFF position. (2) Disconnect power to all
battery chargers. (3) Disconnect all battery cables, negative
(--) leads first. Reconnect negative (--) leads last when
reconnecting the battery cables after servicing. Follow these
precautions to prevent the starting of generator sets by an
automatic transfer switch, remote start/stop switch, or engine
start command from a remote computer. Before servicing any
components inside the enclosure: (1) Remove all jewelry. (2)
Stand on a dry, approved electrically insulated mat. (3) Test
circuits with a voltmeter to verify that they are deenergized.
Important notes about service disconnect to OFF
operation:
D On service entrance transfer switches, the utility
line side lugs are active at all times. The service
disconnect procedure removes power from the load,
but utility power is still present at the transfer switch
lugs whenever the utility source is available.
D Service disconnect transfers to the OFF position,
disconnecting the load from the source when a
source is available.
D Service disconnect transfers to OFF immediately,
ignoring all time delays.
D The generator engine start signal is not activated by
the service disconnect to OFF procedure.
D Further transfer is inhibited after transfer to OFF.
D Moving the switch to the SERVICE DISCONNECT
position during a test or exercise sequence ends the
test or exercise sequence.
D Controller power is not disconnected. The service
disconnect procedure does not remove power from
the controller. To remove power from the controller for
maintenance or service, perform the service
disconnect procedure and then see Section 6.5 for
instructions to use the control circuit isolation switch
to remove power from the controller.
1
GM70609
1. Utility disconnected lamp
2. Service disconnect switch
2
Figure 6-5 Service Disconnect Switch Location
(typical)