Emerson 300 manual Testing & Service, Manual Load Transfer, Trouble-Shooting

TESTING & SERVICE (continued)

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.

PROBLEM	CHECK IN NUMERICAL SEQUENCE
	1 OPERATION	2 GEN-SET	3 VOLTAGE
Gen-Set does not start when	Hold the Transfer Test button	Starting control must be in
the Transfer Test button is	15 sec. or the outage must be	automatic position. Batteries
pressed and held for 15	long enough to allow for the 1	must be charged and
seconds or when the normal	or 3 sec. Momentary Normal	connected. Check wiring to	—
source fails.	Source Outage Delay plus	engine starting contacts.
	engine cranking and starting
	time.
Transfer switch does not	Wait for Transfer to Emergen-	Generator output circuit	Voltmeter should read at least
transfer the load to	cy Delay (0 to 5 min.) to time	breaker must be closed.	90% of nominal phase to
emergency source after the	out. For immediate transfer,	Generator frequency must be	phase voltage between
gen-set starts.	press the Bypass Time Delay	at least 57 Hz.	transfer switch terminals EA
	button. If Motor Load Transfer		and EC (or EL1 and EL2 for 2
	is active, wait for inphase con-		pole switches). *
	dition (see below).		* These are factory settings.
Transfer switch does not	Wait for Retransfer to Normal		Voltmeter should read at least
transfer the load to normal	Delay (1 sec. to 30 min.) to		90% of nominal phase to
source when normal returns	time out. For immediate re–		phase voltage between
or when Transfer Test button	transfer, press Bypass Time	—	transfer switch terminals NB
is released.	Delay button. If Motor Load		and NC, NC and NA, and NA
	Transfer is active, wait for in-		and NB (or NL1 and NL2 for 2
	phase condition (see below).		pole switches).
Gen-Set does not stop after	Wait for the 5 minute	Starting control must be in
load retransfer to the normal	Unloaded Running Delay to	automatic position.	—
source.	time out.

Trouble-Shooting the Motor Load Transfer Feature (refer to page 5–4)

Use extreme caution when using a meter to measure voltages in the following steps. Do not touch power terminals; shock, burns, or death could result !

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, if used. The retransfer 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 controller or the transfer switch, call your local ASCO Power Technologies sales office, representative, or ASI. In the United States, call 1–800–800–2726. Furnish the Serial No., Bill of Material (BOM) No., and Catalog No. from transfer switch nameplate.

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