SECTION 3 BYPASSING & ISOLATING
3---1
BYPASSING THE ATS*
This procedure explains how to Bypass the closed
automatic transfer switch contacts. Bypassing is required
before the ATS can be tested or isolated. The Bypass
Handle must be in the
OPEN
position (green indicator)
and the Isolation Handle must be in the
CLOSED
position (window). See Figures 3–1, 3–2, and 3–3.
You can only bypass to the same source
that the Transfer Switch is connected.
Solenoid interlock prevents incorrect operation.
1. Observe which
Transfer Switch Connected To
light is
on (
Normal
or
Emergency)
on the door. This is the
position of the automatic transfer switch.
2. Bypass to the same source as connected to transfer
switch as follows (select Normal or Emergency).
To Bypass Normal
push in handle
all the way & turn it clockwise.*
To Bypass Emergency
pull out han-
dle all the way & turn it clockwise.*
Indicator shows:
green
●
OPEN when the
ATS is not bypassed.
Indicator shows:
yellow
●
EMERGENCY CLOSED
when ATS is bypassed to Emergency
or
yellow
●
NORMAL CLOSED when
ATS is bypassed to Normal Source.
Figure 3–1. Bypass Handle and position indicators.
To 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 all the way, then turn it
clockwise until
Bypass Switch Position
shows CLOSED on
NORMAL (yellow indicator). The red light
Unit Not In
Automatic
will flash.
E
L
N
Push in
Bypass
Handle
&
turn it
clockwise.
ATS
Bypass Switch
Figure 3–2. Bypass to Normal.
To 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 all the way, then turn it
clockwise until
Bypass Switch Position
shows CLOSED on
EMERGENCY (yellow indicator). The red light
Unit
Not In Automatic
will flash.
E
L
N
ATS
Bypass Switch
Pull out
Bypass
Handle
&
turn it
clockwise.
Figure 3–3. Bypass to Emergency.
The automatic transfer switch can now be put in the
TEST
or
OPEN
position. See
ISOLATING
on page 3–2.
* NOTE
: When Accessory 66A (reversed Normal & Emergency connections) is specified,
the handle push–pull operation is reversed. Follow instructions on the door.