SECTION 3 TESTING & SERVICE
3--1

PREVENTIVE MAINTENANCE

Reasonablecare in preventive maintenance will insure
high reliability and long life for the automatic transfer
switch.
Operatethe switch at least once a month.Performthis
four step ElectricalOperation Test. This is a test with
loadtransfer.

TransferSwi tch Test

1. Press and hold the door-mounted TRANSFER
SWITCHT EST button until the engine starts and
runs. This should happen within 15seconds.
2. The transfersw itchingdevice will operate to the
Emergency position. If the Transfer To Emer-
gencyDelayis used, the transfer will occur after
a time delay (up to 5 minutes). For immediate
transfer press BYPASS TIME DE LAY button.
3. Thetransfer switching device will operate back
to Normalposition after the Retransfer To Nor-
mal Delay (up to 30 minutes). For immediate
retransfer press BYPASS TIME DE LAY button.
4. Unloaded Running (Engine Cooldown) Delay
allows engine to run unloaded for5 minutes.
Clean and inspectthe switch once a year. De-energize
all sources,then brush and vacuum away any excessive
dusta ccumulation. Removethetransf er switch barriers
and check conta ct condition . Thenon–replaceable main
contacts are designed to last the life oft he transferswit ch.
Reinstallthe barriers carefully.
Maintain transfer switch lubrication.Thetransfer
switch has been properlylubricated, and under normal
operating conditions no further lubricatingis required.
Renew factorylubrication if the switch is subjected to
severe dust or abnormal operating conditions.
Relubricate the solenoidoperator if a coil is replaced.
Do not use oil. Order lubrication 625550–001 (Castrol
EndurexR4000 lubricant).
Replacementparts. Replacementparts are available in
kitform. Whenorderingparts provide the Serial No. and
Catalog No. from the transfer switch nameplate.
Contact your local ASCO Power Technologies sales
office.

DISCONNECTING THE CONTROLLER

The harness disconnect plugs are furnished for repair
purposesonly and should not have to be unplugged. Ifthe
controller must be isolated, follow th ese steps carefully.

Disconnecting the Plugs

1. Observe the position of the transfer switching device.
a. If the transfer switching device is in the Normal
position, placestandby engine starting control in the
offposition. Thenopen the emergency source circuit
breaker.
b. If the transfer switching device is in theEmergency
position, open the normal source circuit breaker.
Placet he engine starting control in the test or run
position.
2. Separate the quick disconnect plugs by squeezing
the latches. Do not pull on the harness wires.
3. Label, remove, and tape the signal wires connected
to theengine start terminals on the transferswitch-
ingdevice: TB1 and TB3, or TB1 and TB2.

Reconnecting the Plugs

1. Observe the position of the transfer switching device.
a. If the transferswitch is in the Normal position, be
surethat the standby engine startingcontrol is still
in the off position. Theemergency source circuit
breaker still should be open.
b. If the transferswitch is in the Emer gency position,
normalsource circuit breake r still should be open.
2. Reconnect the signal wires connected to the
appropriate engine start terminalson the transfer
switch. SeeSection 1,Engine Starting Contacts.
3. The harness plugs and sockets are keyed. Carefully
alignthe plugs with the sockets and press straight in
until both latches click.
4. Restore the opposite source as follows:
a. If the transfer switch is in the Normal position,
place the standby engine startingcontrol in the
automatic position. Then close the emergency
source circuit breaker.
b. If thetransferswitchisintheEmergencyposition,
closeth e normal source circuit brea ker. The load will
be automatically retransferred to the normal source
after the Retransferto Normal Delay. For immediat e
retransfer, press BYPASS TIM E DELAY button.
Place the engine starting control in the automatic
position.