Emerson 7000 SERIES 7ADTB manual Return To Service, Bypassing & Isolating, continued

BYPASSING & ISOLATING

(continued)

RETURN TO SERVICE
This procedure explains how to return the automatic	Solenoid interlock prevents you from closing
transfer switch (ATS) to service after inspection and	the isolation contacts until the ATS is in the
maintenance. Observe the Bypass Switch Position indica-	same position as the Bypass Switch.
tor and lights). Refer to Figures 3–7, 3–8, 3–9, and 3–10.	3. Observe which Bypass Switch Position indicator is
1. Slide the transfer switch (ATS) into the enclosure	black (NORMAL or EMERGENCY) at the Bypass
	Switch Handle. This indicates the source connected
(isolation contacts facing inward) until its crank pins
	to the load.
engage the latch plates on both sides. Next push in
	4. Observe which Transfer Switch Connected To light is
side rail carriage. Then close enclosure door.
	on (Normal or Emergency) on the door. This is the
	position of the Transfer Switch. If it is not in the same
	position as the Bypass Handle change the position of
Close the enclosure door to prevent personal
	the Transfer Switch as follows:
injury in case of electrical system fault.

To change the position of transfer switch

Align position indicator. Do not leave the handle in an intermediate position.

Operate to NORMAL	OperatetoEMERGENCY
Turn Transfer Control	Turn Transfer Control
switch to Retransfer	switch to Transfer Test
Delay Bypass.	(hold 15 seconds).*
Connected To Normal	Connected To Emergency

CONN TEST

position window

light should come on. light should comes on.

* If Feature 2B time delay is used, there will be a delay

before transfer to Emergency.

ISOLATE

unfold crank

clockwise – draws in the Transfer Switch

Figure 3–8. Isolation Handle.

NOTE: With Normal available, the automatic

transfer switch will not stay in the emergency

position unless Feature 3A time delay is used

(at least 30 seconds).

Do not close the isolation contacts unless the Transfer Switch (ATS) and Bypass Switch are in the same position!

5.When the transfer switch is in the same position as the Bypass Switch handle, continue turning the

2. Turn the Isolation Handle clockwise (approx. 7

turns) until the window shows TEST. The ATS can be

Isolation Handle clockwise (about 16 turns) until the window shows CONN (connected).

tested now without load interruption (see page 2–1).

Bypass Switch E

Turn crank
clockwise	L
until
window
shows
TEST.
	N

Turn crank clockwise until window shows

CONN (connected).

Bypass Switch	E
	L
	N
ATS

ATS

Figure 3–9. ISOLATE to TEST position.

Figure 3–10. TEST to CONNECTED position.

Now continue to the next page for instructions on how to return the Bypass Handle to the OPEN postition.

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