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TESTING & SERVICE
(continued)
3 --- 2
MANUAL LOAD TRANSFER
This procedure will manually transfer the load if the
controller is disconnected.
Do not manually operate the transfer switch
until both power sources are disconnected:
open both circuit breakers.
1. Open normal and emergency source circuit breakers.
2. Use the maintenance handle to manually operate
transfer switch to the opposite source. See page
1–3, Manual Operation Test .
3. If the transfer switch is in the Emergency position
manually start the engine generator and then close
the emergency source circuit breaker.
TROUBLE- SHOOTING
Note the control features that are activated or
furnished on the switch and review their operation.
Refer to Section 5, Control Features.
Proceed with care! The automatic
transfer switch is energized.
Table 3-1. Trouble-Shooting Checks.
P
R
O
B
L
E
M
CHECK IN NUMERICAL SEQUENCE
P
R
O
B
L
E
M
1OPERATION 2 GEN-SET 3VOLTAGE
Gen-Set does not start when
the Transfer Test button is
pressed and held for 15
seconds or when t he normal
source fails.
Hold the Transfer Test button
15sec.ortheoutagemustbe
long enough to allow for the 1
or 3 sec. Momentary Normal
Source Outage Delay plus
engine cranking and star ting
time.
Starting control must be in
automatic position. Batteries
must be charged and
connec ted. Check wiring to
engine starting contacts.
—
Transfer switch does not
transfer the load to
emergency source after the
gen-set starts.
Wait for T ransfer to Emergen-
cy Delay (0 to 5 min.) to time
out. For immediate transfer,
press the Bypass Tim e Delay
button. If Motor Load Transfer
is active, wait for inphase con-
dition (see below).
Generator output c ircuit
breaker must be closed.
Generator frequency must be
at least 57 Hz.
Voltmeter sho uld read at least
90% of nominal phase to
phase voltage between
transfer switch terminals EA
and EC (or EL1 and EL2 for 2
pole switches). *
* These are factory settings.
Transfer switch does not
transfer the load to normal
source when normal returns
or when Transfer Test button
is released.
Wait for Retransfer to Normal
Delay (1 sec. to 30 min.) to
time out. For immediate re–
transfer, press Bypass Tim e
Delay button. If Motor Load
Transfer is active, wait for in-
phase condition (see below).
—
Voltmeter sho uld read at least
90% of nominal phase to
phase voltage between
transfer switch terminals NB
and NC, NC and NA, and NA
and NB (or NL1 and NL2 for 2
pole switches).
Gen-Set does not stop after
load retransfer to the normal
source.
Wait for the 5 minute
Unloaded Running Delay to
time out.
Starting control must be in
automatic position.
—
Trouble-Shooting th e Motor Load Transfer Feature (refer to page 5–4)
Useextremecautionwhenusingameter
to measure voltages in the following steps.
Do not touch power t erminals; shock,
burn s , or death could res u lt !
1. Connect a voltmeter (set for twice system
phase–to–phase voltage) between Transfer Switch
terminals NA and EA.
2. Manually start generator. Voltmeter needle should
sweep back and forth at a regular rate between 0
and about twice system voltage.
3. Press and hold
Transfer Test button. The load
should transfer to emergency source when meter
needle is near 0 volts. If transfer does not occur,
Motor Load Transfer feature is not operating.
4. Release the Transfer Test button. The load should
retransfer back to the normal source after the
Retransfer to Normal Delay,ifused. Theretransfer
should occur when the needle is near 0 volts. If
retransfer does not occur after the time delay, the
Motor Load Transfer feature is not operating.
5. For immediate retransfer, press the Bypass Time
Delay button. Then disconnect the voltmeter.
If the problem is isolated to circuits on the c ontroller or the transfer switch, c all your local ASCO Power Technolog ies
sales office, representative, o r ASI. In the Unite d States, ca ll 1–800–800–2726. Furnish the Serial No., Bill of
Material (BOM) No., and Catalog No. from transfer switch nameplate.