Emerson 7ATB manual BYPASSING & ISOLATING continued, RETURN TO SERVICE continued

BYPASSING & ISOLATING (continued)

RETURN TO SERVICE continued*

This procedure explains how to return the Bypass Switch Handle to the OPEN position. The Bypass Handle must be in the CLOSED position (yellow indicator on NORMAL or EMERGENCY) and the Isolation Handle must be in the TEST position (window). If the handles are not in these positions, refer to Return to Service on page 3–3. See Figures 3–11, 3–12, and 3–13.

You can only bypass to the same source that the ATS is connected. Solenoid interlock prevents incorrect operation.

1Observe which Bypass Switch Position indicator is yellow (NORMAL or EMERGENCY) at the Bypass Switch Handle. This indicates the source connected to the load.

2Un–Bypass to same source as the Bypass Switch Position as follows (select Normal or Emergency).

Indicator shows:

green O OPEN when the ATS is not bypassed.

To un–Bypass Normal push in handle all the way & turn it counterclockwise.*

Indicator shows:

yellow O EMERGENCY CLOSED when ATS is bypassed to Emergency or

yellow O NORMAL when ATS is bypassed to Normal Source.

To un–Bypass Emergency pull out handle all the way & turn it counterclockwise.*

Figure 3–11. Bypass Handle and position indicators.

To Un–Bypass Normal Source*

(Load connected to Normal Source)

The Transfer Switch Connected To Normal light is on and Transfer Switch Connected To Emergency light is off.

Push in* the Bypass Handle then turn it counterclock- wise until Bypass Switch Position shows OPEN (green indicator). The Unit Not in Automatic light should be off.

Push in	Bypass Switch	E
Bypass
Handle
&
turn it
counter-		L
clockwise.
		N
	ATS
Figure 3–12. Un–Bypass Normal.

To Un–Bypass Emergency Source*

(Load connected to Emergency Source)

The Transfer Switch Connected To Emergency light is on and Transfer Switch Connected To Normal light is off.

Pull out* the Bypass Handle then turn it counterclock- wise until Bypass Switch Position shows OPEN (green indicator). The Unit Not in Automatic light should be off.

Pull out	Bypass Switch	E
Bypass
Handle
&
turn it
counter-		L
clockwise.
		N
	ATS
Figure 3–13. Un–Bypass Emergency.

The Automatic Transfer & Bypass–Isolation Switch should be left in this position.

*NOTE: When Accessory 66A (reversed Normal & Emergency connections) is specified, the handle push–pull operation is reversed. Follow instructions on the door.

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