GE AK-50 Series - Separation of Front and Rear Frames

Low
Voltage
Power
Circuit
Breakers
GEK
-
7303
5
.
Remove
the
auxiliary
switch
operating
rod
(
&
,
Fig
.
20
)
.
At
all
times
it
is
important
not
to
permit
pencil
lines
,
paint
,
oil
or
other
foreign
mater
-
ials
to
remain
on
the
insulating
surfaces
of
the
breaker
as
they
may
cause
low
resistance
between
points
of
different
potential
and
result
in
eventual
electrical
breakdown
.
6
.
Check
along
the
trip
shaft
for
a
mech
-
anical
interference
or
connection
between
the
overcurrent
trip
device
and
the
trip
paddles
.
Remove
mechanical
connection
if
present
,
or
if
interference
exists
,
use
extreme
care
when
removing
or
re
-
assembling
front
and
back
frames
to
avoid
mechanical
breakage
of
trip
devices
.
In
reassembling
the
front
and
rear
frames
,
the
two
frames
should
be
positioned
vertically
so
that
the
trip
shaft
is
horizontally
aligned
.
NOTE
:
be
fastened
to
a
suitable
maouting
base
with
the
front
frame
supported
by
a
sling
or
hook
as
the
bolts
are
being
installed
.
The
breaker
should
be
operated
several
times
at
a
rated
voltage
to
assure
that
the
control
circuits
are
properly
connected
and
that
all
electrical
attachments
are
functioning
properly
.
A
complete
contact
inspection
,
including
con
-
tact
wipe
and
pressure
,
should
be
made
at
regu
-
lar
inspection
periods
and
always
after
a
known
short
circuit
current
has
been
interrupted
,
to
determine
whether
the
contacts
are
worn
or
pitted
in
which
case
they
should
be
dressed
or
replaced
.
It
is
necessary
to
remove
the
arc
quenchers
to
properly
inspect
the
contacts
.
Arc
-
ing
contacts
and
arc
quencher
barriers
should
be
replaced
when
they
are
eroded
to
half
their
original
thickness
.
It
is
recommended
that
the
breaker
BASIC
BREAKER
COMPONENTS
ARC
QUENCHERS
(
Fig
.
4
and
5
)
The
arc
quenchers
should
be
inspected
at
the
If
the
barriers
are
LUBRICATION
regular
inspection
period
,
cracked
or
eroded
to
one
-
half
their
original
thickness
,
they
should
be
replaced
.
In
general
,
the
circuit
breaker
requires
mod
-
Mechanical
bearing
points
erate
lubrication
,
and
sliding
surfaces
should
be
lubricated
at
the
regular
inspection
periods
with
a
thin
film
of
G
-
E
Lubricant
D
50
H
15
.
Sliding
silver
plated
con
-
tact
surfaces
should
be
lubricated
with
G
-
E
Lub
-
ricant
D
50
H
47
.
Hardened
grease
and
dirt
should
be
removed
from
latch
and
bearing
surfaces
by
using
kerosene
.
ALL
EXCESS
LUBRICANT
SHOULD
BE
REMOVED
TO
AVOID
ANY
ACCUMULATION
OF
DIRT
OR
DUST
.
REPLACEMENT
—
AK
BREAKERS
Be
sure
the
breaker
is
open
.
1
.
2
.
Remove
the
channel
-
shaped
retaining
bar
by
removing
two
screws
and
two
nuts
.
3
.
Lift
the
quenchers
clear
of
the
movable
arcing
contacts
.
4
.
During
replacement
be
careful
not
to
overtighten
the
screw
which
secure
the
channel
-
shaped
retaining
bar
.
Overtightening
the
screws
will
bow
the
bar
and
leave
the
center
arc
quen
-
cher
loose
.
The
use
of
cotton
waste
to
wipe
bearing
surfaces
should
be
avoided
,
as
the
cotton
ravelings
may
become
entangled
under
the
bearing
surfaces
and
destroy
the
surface
of
the
bearing
.
On
drawout
breakers
,
the
contact
surface
of
the
disconnect
studs
should
be
greased
with
G
-
E
Grease
Specification
D
50
H
47
.
SEPARATION
OF
FRONT
AND
REAR
FRAMES
To
repair
or
replace
contacts
,
operating
mech
-
anism
,
or
the
overcurrent
devices
,
the
front
frame
must
be
separated
from
the
back
frame
.
To
separate
the
two
frames
proceed
as
follows
:
1
.
The
breaker
contacts
must
be
open
with
the
safety
pin
in
place
.
(
See
MAINTENANCE
.
)
2
.
Remove
the
two
opening
springs
(
on
lower
part
of
the
breaker
)
from
the
outside
pole
units
.
3
.
Remove
the
clevis
pin
(
14
,
Fig
.
6
)
(
13
,
Fig
.
7
)
from
the
center
pole
unit
.
4
.
Remove
the
six
nuts
from
the
back
frame
using
a
socket
wrench
with
an
extension
.
These
include
the
two
nuts
at
the
top
of
the
frame
.
REPLACEMENT
—
AKF
BREAKERS
The
center
-
pole
arc
quencher
of
these
breakers
is
similar
to
the
arc
quenchers
of
the
standard
breakers
and
is
replaced
in
a
similar
manner
,
except
that
the
breaker
must
be
closed
.
With
the
breaker
closed
the
center
-
pole
contacts
are
open
and
the
arc
quencher
can
be
removed
.
Replace
the
outer
-
pole
arc
quenchers
of
the
Type
AKF
breaker
as
follows
:
1
.
Be
sure
the
breaker
is
open
.
2
.
Remove
the
two
channel
-
shaped
retaining
bars
which
bear
against
the
front
of
the
arc
quenchers
by
removing
four
screws
,
two
on
each
side
.
3
.
Lift
the
arc
quenchers
clear
of
the
movable
arcing
contacts
.
4
.
Replace
arc
quenchers
and
insert
the
four
screws
holding
the
retaining
bars
in
position
.
7
Courtesy of NationalSwitchgear.com