Electrical Operation, Automatic Transfer

observe these lights

INSTALLATION (continued)

			Automatic Transfer
			& Bypass–Isolation Switch
		Transfer
Transfer Switch	Transfer Switch	Control
Connected	Connected	Retransfer	Transfer
To	To	Delay	Test
Normal	Emergency	Bypass	(15HOLDSECONDSFOR )
GREEN	RED		operate
			this switch
Normal	Emergency
Source	Source
Accepted	Accepted
GREEN	RED

Figure 1-13. Standard controls and indicators.

3 – Electrical Operation

This procedure checks electrical operation of the ATS.

Be sure to close all enclosure doors

before proceeding to prevent personal injury

in case of electrical system fault.

Transfer Test

The ATS should still be bypassed and isolated. Both normal and emergency sources must be available and the emergency source generator (if used) must be capable of being started; put engine starting control in automatic position. The Transfer Switch Connected to Normal light and the Normal Source Accepted light should be on.

1.Turn Isolation Handle clockwise about 7–8 turns until TEST light comes on, DISCONNECTED light off.

2.Perform steps 1–5 at right. Observe the status lights.

■Black square means light is on.

❐White square means light is off.

3.Turn the Isolation Handle clockwise until it stops (about 6 or 7 turns). The CONNECTED light should come on, TEST light off. Remove the Isolation Handle and store it inside the enclosure on the carriage frame on the right side.

4.Turn the Bypass Handle clockwise to the AUTO- MATIC POS position. The Bypass Switch CLOSED ON NORMAL light should go off.

This completes the Functional Test of the ATB. The genera- tor’s starting control should be left in automatic position.

The Transfer Switch Connected

1to Normal and Normal Source Accepted lights should be on.

Turn and hold Transfer Control switch clockwise to Transfer

2Test until the engine starts and runs (within 15 sec.). The Emergency Source Accepted light should come on.

Transfer switch will operate to the Emergency position after Feature 2B time delay. The

3Transfer Switch Connected To Emergency light should come on and Load Connected to Normal light goes off.

Transfer switch will operate back to Normal position after Feature 3A time delay. For im- mediate retransfer turn Transfer

4Control counterclockwise to Retransfer Delay Bypass. The Transfer Switch Connected To Normal light should come on; Transfer Switch Connected to Emergency light should go off.

The engine–generator will stop after the Feature 2E time delay

5(unloaded running engine cool- down). The Emergency Source Accepted light should go off.

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