Emerson ASCO 7000 - Manual (Page 8)

TESTING & SERVICE
(continued)
2---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
(all conductors deenergized).
1. Deenergize both the normal and emergency source
conductors (remove fuses or open circuit break-
ers).
2. Use the maintenance handle to manually operate
the transfer switch to the opposite source. See
Manual Operation on page 1–2.
3. If the transfer switch is in the Emergency position
manually start the engine generator and then
install emergency source fuse or close the circuit
breaker.
TROUBLE-SHOOTING
Note any optional accessories that may be furnished on
the automatic transfer switch (ATS) and review their
operation. Refer to any separate drawings and/or
instructions that may be packed with the ATS.
Hazardous voltage capable of causing shock,
burns, or death is used in this switch.
Do not touch the power or load terminals
of the transfer switch!
Table 2-1. Trouble-Shooting Checks.
CHECK IN NUMERICAL SEQUENCE
PROBLEM 1
OPERATION
2
GEN-SET
3
VOLTAGE
Engine–generator set does
not start when the Transfer
Control switch is turned and
held in Transfer Test position
or when the normal source
fails.
Hold Transfer Test switch 15
seconds or the outage must
be long enough to allow for
Feature 1C time delay plus
engine cranking and starting
time.
Starting control must be in the
automatic position. Batteries
must be charged and
connected. Check wiring to
engine starting contacts on
customer terminal block TB.
Verify that the small plug J3 is
connected to receptacle P3.
–
Transfer switch does not
transfer the load to the
emergency source after the
engine–generator set starts.
Wait for Feature 2B time delay
to time out (if used).
Generator output circuit
breaker must be closed.
Generator frequency must be
at least 95% of nominal
(57 Hz for a 60 Hz system.) *
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). *
Transfer switch does not
transfer the load to normal
source when normal returns
or when the Transfer Control
switch is released.
Wait for Feature 3A time delay
to time out (if used).
–
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).
Engine–generator-set does
not stop after load retransfer
to the normal source.
Wait for Feature 2E time delay
to time out (if used).
Starting control must be in the
automatic position. –
* These are factory settings. Refer to the Group 5 Controller User’s Guide.
If the problem is isolated to circuits on the controller or the transfer switch, call your local ASCO Power Technologies
sales office or ASI. In the United States, call 1–800–800–2726. In Canada, call 1–888–234–2726. Furnish the Serial
No., Bill of Material (BOM) No., & Catalog No. from transfer switch nameplate.