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 United States, call 1–800–800–2726 or email customercare@asco.com. In Canada, call 1–888–234–2726. Furnish the Serial No., Bill of Material (BOM) No., & Catalog No. from transfer switch nameplate.

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