GE AKD-6 - Rackout Mechanism Operation for AKR Breakers

Low
Vohage
Switchgeo
r,
GEK-72101
-1#
q.)'
L
&*-
FlG. 20
(75E180001)
Rockout mechonism
for AKR breqkers
I n),.i-
llll
ll'j-.-.'-
tp
,/
L
The
DISCONNECTED
and CONNECTED
positions
are
indicated
by the sight indicator
and by the
jackscrew
reach-
ing the end
of
its
travel. The adjusting nuts
(78)
are set so
that
when the CONNECTED
position
is reached, the
pin
and the
interlock tube slot
will be
aligned
and the breaker
can be closed
upon
removal
of the rackout handle. In
the
DISCONNECTED position,
it may be necessary
to rotate
the
jackscrew
pin
to match
the slot in the interlock
tube.
The motion
of the rackout
mechanism can
be reversed
at any
point
in the
cycle by reversing the
direction of
ro-
tation of the handle.
EMERGENCY
OPERATION
If necessary,
it is
possible
to remove
the breaker
from
the
house
without using the rackout
mechanism.
This is
done
by rotating the
track lock
links
after the
breaker has
been tripped
and
pulling
the breaker manually
off of the
primary
disconnects.
Ffowever,
the breaker
cannot be reinserted into
the house
far enough
to engage
the
primary
disconnects
unless the
stop
links
(49,
50) are retracted.
The stop links retract
automatically
when normal
racking
procedures
are
used.
If
it is necessary
to insert
the breaker into
the house
when the
rackout mechanism
is in the
CONNECTED
posi-
tion, the
stop links must
be retracted and held
until the
interference
pin
or
the breaker mounting
pin
has
passed
the
stop link. It
is recommended
that the
stop
link
be held
up
with masking
tape
when attempting
to insert the breaker
in
this manner.
The inertia
of the breaker can then
be used to
aid in
pushing
it onto the
primary
disconnects.
RACKOUT MECHANISM
OPERATION
AKR BREAKERS
Part
numbers in Figure
20 refer to sheet and
part
num-
bers
in
the
0673D0500
series
of drawings.
The
rackout mechanism for AKR breakers
is mounted
on the breaker itself and a description
and details of this
mechanism are
given
in Maintenance Manual
GEK-7310.
The rackout mechanism is operated by
pushing
the
handle
onto the end
of the
jackscrew
shaft and rotating
the
handle.
Clockwise rotation
moves the breaker
into
the
house and counter-clockwise rotation moves the breaker
out. Approximately 18 turns of the handle will
move
the
breaker from the
DISCONNECTED
to the
CONNECTED
position.
The rackout mechanism is interlocked so that
the circuit
breaker
must
be open before
the operating handle can be
inserted.
When the breaker is closed,
an interlock link
operated by the breaker mechanism locks the sliding
cover
over the racking screw in the breaker escutcheon. To insert
the
racking
handle the trip button must be depressed, and
the sliding cover
pushed
to the right. When the handle is
insert-:d the cover is held open and the breaker is in a
trip free condition. As long as the handle is engaged, the
breaker remains trip free.
There is also a
stationary cam in the house which
holds
the
breaker trip
free as it is moved between the CONNECTED
and
TEST
positions
by
keeping a lever
which is connected
to
the breaker trip shaft
in the raised
position.
See Figure
20,
part
841-01. This stationary
cam comes into
oper..tion
before the
primary
disconnects have
parted
and is operable
whether or not the rackout
handle
is engaged.
The
breaker
25