Breaker Accessories; Primary Disconnects - Ak-50 Only; Secondary Disconnects - GE AK-2-50 Maintenance Manual

GEK-7303 Low Voltage Power Circuit Breakers
For the exact characteristics and setting of
each breaker in a selective system, reference
should l>e made to the coordination chart furnished
for the particular system.
BREAKER ACCESSORIES
PRIMARY DISCONNEOS
- AK-50 ·ONLY
The primary discoruiects are attached to the
circuit breaker studs at the rear of the breaker
base. Each disconnect assembly consists of four
pairs - of opposed contact fingers. The contact
fingers are secured to the breaker stud by two
bolts which pass thrpugh the assembly and the
stud of the enclosure; the disconnect fingers
exert a set amount of force against the stationary
stud through the action of the compression springs.
Retainers and spacers hold the contact fingers in
correct. alignment for engagemenf with the stud.
The amount of force which the fingers exert
against the stud is determined _ b y the degree to
-which the springs are compressed by the bolt and
nut ~hich _ hold the assembly toge~~r. ·
REPLACEMENT
If
for any reason . the disconnects must be
replaced . or _ removed, the position of the nuts on
the bolts should be carefully noted and the number
of turns of the nuts shoula be counted, so that
in reassembly the original amount of compression -
can be restor~d by replacing the nuts to their
fo.rmer position on the bolts.
The primary disconnects should always be
kept lubricated with G.E. Co. D50H47 grease.
SECONDARY DISCONNECTS
· The secondary disconnects· for all breakers
serve as connections between breaker control cir-
cuit elements and .external control circuits. They
are are used only on drawout breakers and . are
--mounted on a horizontal cross-channel at the top
rear of the breaker. A terminal board serves
the same · purpose on stationary mounted and
general purpose enclosure .mounted breakers.
These secondary disconnects allow removal of the
breaker without the necessity of having to detach
external connections.
The movable part of the secondary disconnects
consists of an insulating body which holds a
_ conducting spring-loaded plunger to which a flex-
ible lead is attached. As the breaker moves
into its enclosure, the plunger is -depressed. by
sliding onto the stationary disconnects of the
enclosure.
REPLACEMENT
1. Unfasten disconnect body from breaker
cross-channel.
2. Open tabs which hold wires on inner side.
3. Pull contact tip loose from hollow tube.
4. · Remove contact tip by cutting wire at its
base.