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Fig.
6
positive Interlock
CLOSED DOOR BREAKER RACKING
The
circuit
breaker
can
be
racked
in
and out
of
the
"Con-
nect" positiori with the front door of the breaker
cubicle
closed.
For
maximum
safety
the breaker must
always
be
racked
with
the
front
door
closed when
primary
power
is
con-
nected.
Make
sure
the breaker is
open before
attempting
to
rack the breaker. The breaker is installed
in
the
breaker
cubicle
as
described
in BREAKER INSTALLATION AND
REMOVAL.
Engage
the racking arms and then
close the
front door ofthe unit
and
secure
it.
Insert the
racking
handle
into
the
hole
in
the
left
side
of
the
front
door
and
engage
the
racking
mechanism
by
pushing
it
in fully.
Rack
the
breaker
by
rotating
the handle clockwise
(60
turns
are
required)
until
a positive
stop
is felt.
The breaker
is
now
in
the
fully
con-
"nected
position
and the
tape
indicator
should
read
"Conn".
To
rack the circuit
breaker
from
the "Connected"
to
the
"Disconnect/Test" position
be sure
that
the
breaker
is open
then
turn
the handle counterclockwise.
CAUTION: RACKING TORQUE NOT TO
EXCEED
60
FOOT-LBS.
(8.292
METER-KG.)
REMOTE RACKING ATTACHMENT
The
breaker can
be
racked
between the
*Dsconnect/Test"
and
*Connected"
positions
electrically
using the
remote
rack-
ing
device.
See
DESCRIPTION
-
REMOTE RACKING
OPERATOR.
POSITIVE INTERLOCK
The positive interlock functions
to
prevent racking
a
breaker
between
the
"Connect"
and the
"Disconnect/Test"
positions
except
when the
primary
contacts are
open.
The
positive
interlock
consists
of a bar which
protrudes
frorn
the
left
side
of
a
closed
breaker to
engage
a
slot
in
the
left-side racking
mechanism when the breaker
is
in
either the
"Disconnect/ Test"
or
"Connected" position. When
the
inter-
lock
is
engaged,
the
racking
mechanism
cannot
be
operated.
(See
Fig.
6.)
8
I
- trnterlock
-
2
-
Racking Shaft
3
-
Rail
4
-
Slot
To
test the
function of
the positive
interlock
install
a
cir-
cuit
breaker
following
the irnstructions given
under tsR.EAK-
ER
INSTALLATION AND REMOVAL. For
the
test, the
control power circuits
in
the
breaker
cubicle must be
en-
ergized.
Place
the
breaker
-in
the "'Disconnect/Test"
position
and
connect
the
secondary disconnect device by
pulling down
on
the breaker handle and
horizontally
inserting the iever arm
fully into
the
breaker
to
engage
the
secondary disconnects.
This
will
actuate the spring-charging
motor
and
charge the
breaker-closing
springs. Close the
front door
of
the
unit
and
secure
it. BEFORE PROCEEDING WITH THIS CHECK,
IT
IS NECESSARY THAT THE PRIMARY CIRCUITS
BE DE-ENERGIZED.
Close
the
breaker
with the control
switch on
the
front of
the door then attempt
to
insert
the
racking
handle
into
the
hole
in
the
unit
door. A definite
stop
should
be encountered
preventing
the socket
on
the
racking
handle
from
engaging
the racking
mechanism.
Trip
the breaker and rack
it
into
the
connected
positionl
AGAIN
IT
IS EMPHASIZED THAT THE PRIMARY
CIRCUITS MUST
BE
DE-ENERGIZED BEFORE
MAK-
ING THIS CHECK OF THE POSITIVE INTERLOCK.
Close
the breaker and
attempt to
insert
the
racking
handle.
A
definite stop should
be
encountered
preventing
the socket
on the racking
handle
from
engaging
the racking
mech-
anism.
If
the
interlock
does
not
function
as
indicated
in
either
of
the
above
cases
DO NOT MAKE ANY ADJUSTMENT.
COMMUNICATE
WITH THE
NEAREST GENERAL
ELECTRIC COMPANY APPARATUS AND SERVICE
ENGINEERING OFFICE FOR IhISTRUCTIONS.
NEGATIVE INTERLOCK
The
negative
interlock functions to hold
the breaker
in
a
mechanical
and electrical trip-free mode when
it
is
being
racked
between the
"Disconnect/Test"
and
"Connect"
posi-
tions. As
an added
precaution
the negative
interlock
will trip
the breaker and hold
it
trip-free
if
an attempt is
made
operate
the racking
mechanism when
the
breaker is
clos,.
unO
in
either
the
"Disconnect/Test'"
or "Connect"
positionl
and the positive
interlock fails to ftlnction.
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