Installation Manual
ASCO 3ATS, 3ADTS, 3NTS, 3NDTS
381333-406
ASCO Power Technologies
Page 7
Troubleshooting
Check in Numerical Sequence
Problem
1 Operation
2 Generator 3
Voltage
For 3ATS & 3ADTS the engine-
generator set does not start when
the transfer test button is pressed
or when the Normal source fails.
The outage must be long
enough to allow for the
feature 1C time delay plus
engine cranking and starting
time.
Starting control must be
in automatic position.
Batteries must be
charged and connected.
Check wiring to the
engine starting contacts.
-
For 3ATS & 3ADTS the transfer
switch does not transfer the load
to the emergency source after the
gen-set starts.
Wait for the feature 2B time
delay. For immediate
transfer, press the transfer
button (bypass timer). If
inphase transfer is active,
wait for inphase condition.
For 3NTS & 3NDTS press
the transfer button.
Is the generator
accepted light on?
Generator output circuit
breaker must be closed.
Generator frequency
must be correct.
Voltmeter should 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). *
* There are factory settings.
For 3ATS & 3ADTS the transfer
switch does not transfer the load
to normal source when normal
returns or after transfer test.
Wait for the feature 3A time
delay. For immediate
retransfer, press the transfer
button (bypass timer). If
inphase transfer is active,
wait for inphase condition.
For 3NTS & 3NDTS press
the transfer button.
-
Voltmeter should 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).
For 3ATS & 3ADTS the
generator does not stop after load
retransfer to the normal source.
Wait for the feature 2E
delay.
Starting control must be
in automatic position.
-
For 3ADTS & 3ADTS the load is
deenergized (off).
Load
Disconnect Timer
on display.
Wait for the delayed-
transition transfer timer. See
User’s Guide 381333-400.
-
Not in auto light is always on.
For 3NTS & 3NDTS this
light is always on, indicating
it is a manual transfer
switch.
- -
Alert light is on.
Read the display for more
information. Refer to
User’s Guide 381333-400.
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