SECTION 3 TESTING & SERVICE
3---1
PREVENTIVE MAINTENANCE
Reasonable care in preventive maintenance will insure
high reliability and long life for the automatic transfer
switch.
Operate the switch at least once a month
. Perform this
four step Electrical Operation Test. This is a test with
load transfer.
Transfer Switch Test
1. Press and hold the door-mounted
Transfer Test
button until the engine starts and runs. This
should happen within 15 seconds.
2. The transfer switch will operate to the Emergency
position. If the
Transfer To Emergency Delay
is
used, the transfer will occur after a time delay
(up to 5 minutes). For immediate transfer press
Bypass Time Delay
button.
3. The Transfer Switch will operate back to the
Normal position after the
Retransfer To Normal
Delay
(up to 30 minutes).
For immediate
retransfer press
Bypass Time Delay
button.
4.
Unloaded Running (Engine Cooldown) Delay
allows engine to run unloaded for 5 minutes.
Clean and inspect the switch once a year.
De-energize all
sources, then brush and vacuum away any excessive dust
accumulation. Remove the transfer switch barriers and
check contact condition. Replace contacts when pitted or
worn excessively. Reinstall the barriers carefully.
Maintain transfer switch lubrication
. The transfer
switch has been properly lubricated, and under normal
operating conditions no further lubricating is required.
Renew factory lubrication if the switch is subjected to
severe dust or abnormal operating conditions.
Relubricate the operator if TS coil is replaced. Order
lubrication kit 75-100
.
Replacement parts.
Replacement parts are available in
kit form. When ordering parts provide the Serial No. and
Catalog No. from the transfer switch nameplate. Contact
your local ASCO Power Technologies sales office,
representative, or ASI. In the United States call
1–800–800–ASCO
(2726),
or
in
Canada
call
1–888–234–ASCO (2726).
DISCONNECTING THE CONTROLLER
The harness disconnect plugs are furnished for repair
purposes only and should not have to be unplugged. If the
controller must be isolated, follow these steps carefully.
Disconnecting the Plugs
Do not unplug the controller until step
1a. or 1b. below is completed.
1. Observe the position of the transfer switch.
a. If the transfer switch is in the
Normal
position, place
standby engine starting control in the
off
position.
Then open the emergency source circuit breaker.
b. If the transfer switch is in the
Emergency
position,
open the normal source circuit breaker. Place the
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 the engine start terminals on the transfer switch:
TB1 and TB3, or TB1 and TB2.
Reconnecting the Plugs
Do not reconnect the controller until step
1a. or 1b. and 2 below are completed.
1. Observe the position of the transfer switch.
a. If the transfer switch is in the
Normal
position, be
sure that the standby engine starting control is still
in the
off
position. The emergency source circuit
breaker still should be open.
b. If the transfer switch is in the
Emergency
position,
normal source circuit breaker still should be open.
2. Reconnect the signal wires connected to the
appropriate engine start terminals on the transfer
switch. See
Section 1
,
Engine Starting Contacts
.
3. The harness plugs and sockets are keyed. Carefully
align the 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 starting control in the
automatic
position. Then close the emergency
source circuit breaker.
b. If the transfer switch is in the
Emergency
position,
close the normal source circuit breaker. The load will
be automatically retransferred to the normal source
after the
Retransfer to Normal Delay
. For immediate
retransfer, press
Bypass Time Delay
button. Place the
engine starting control in the
automatic
position.
