Asco 7000 Series - Bypass to Normal Source; Bypass to Emergency Source

Bypassing & Isolating Installation Manual
381333-415 B 13
RETURN TO SERVICE
This procedure explains how to return the automatic
transfer switch (ATS) to service after inspection and
maintenance. Observe the Bypass Switch Position
indicator and lights). Refer to Figures 14 through 18.
1. Slide the transfer switch (ATS) into the enclosure
(isolation contacts facing inward) until its crank pins
engage the latch plates on both sides. Substantial
force is required to overcome detents on the rails.
Next push in side rail carriage. On 4000 A first
retract the two legs and lock them in place. See
Figures 14 and 15.
Then close enclosure door(s).
Close the enclosure door to prevent personal
injury in case of electrical system fault.
Align the position indicator. Do not leave
the handle in an intermediate position.
Figure 16. Isolation Handle.
2. Turn the Isolation Handle clockwise (approx. 7
turns, approx. 8 turns for 4000 A) until the window
shows TEST. The ATS can be tested now without
load interruption (see page 8).
Figure 17. ISOLATE to TEST position.
Solenoid interlock prevents closing the isolation
contacts until the ATS is in the same position as
the Bypass Switch.
3. Observe which Bypass Switch Position indicator is
black (NORMAL or EMERGENCY) at Bypass
Switch Handle. This shows the source connected to
the load.
4. Observe which Transfer Switch Connected To light
is 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 the Transfer Switch as follows:
To change the position of transfer switch
Operate to NORMAL Operate
to EMERGENCY
Turn Transfer Control
switch to Retransfer
Dela
y
B
y
pass.
Turn Transfer Control
switch to Transfer Test
(
hold 15 seconds
)
.*
Connected To Normal
li
g
ht should come on.
Connected To Emergency
li
g
ht should comes on.
* If Feature 2B time delay is used, there will be a
delay before transfer to Emergency.
With Normal available, the ATS 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
Isolation Handle clockwise (approx. 16 turns,
approx. 12 turns for 4000 A) until the window shows
CONN (connected).
Figure 18. TEST to CONNECTED position.
Continued on next page
unfold
crank
position
window
clockwise
–
draws in the Transfer Switch
CONN
TEST
ISOLATE
E
L
N
Turn crank
clockwise
until
window
shows
TEST.
ATS
Bypass Switch
E
L
N
Turn crank
clockwise
until window
shows
CONN
(connected).
ATS
Bypass Switch