GE AK-50 User Manual

G
£
1
-
74600
Low
-
voltage
Power
Circuit
Breakers
1
.
Muffler
A
ssembly
2
.
Spacer
Block
3
.
Inner
Ba rrier
4
.
Cap
5
.
Intermediate
Barrier
6
.
Outer
Barrier
7
.
Si de
Plate
Disoisemb
/
ed
ore
quenene
AKF
oufer
pc
/
c
:
DISASSEMBLY
—
AKF
OUTER
POLES
(
Fig
.
5
)
Table
1
gives
the
figures
for
contact
pressure
and
contact
wipe
.
Both
wipe
and
pressure
should
be
checked
dur
-
ing
the
regular
inspection
period
.
MEASURING
CONTACT
WIPE
(
Fig
.
6
)
1
.
Remove
arc
quenchers
(
see
RE
-
PLACEMENT
under
ARC
QUEN
-
CHER
)
.
2
.
With
the
breaker
open
,
measure
the
horizontal
distance
from
the
edge
of
the
stationary
contact
to
the
sta
-
tionary
block
behind
it
.
(
"
B
"
dim
.
for
arcing
contacts
,
"
CM
dim
.
for
main
contacts
.
)
3
.
Close
the
breaker
and
repeat
item
2
.
The
difference
between
the
readings
in
items
2
and
3
determines
the
wipe
of
the
contacts
.
For
safety
reasons
be
extremely
careful
not
to
trip
the
breaker
.
MEASURING
CONTACT
PRESSURE
(
Fig
.
6
)
1
.
Remove
arc
quenchers
(
see
RE
-
PLACEMENT
under
ARC
QUEN
-
CHER
)
.
2
.
Close
the
breaker
and
measure
dimension
"
B
"
.
3
.
Open
the
breaker
.
Place
a
push
-
type
scale
against
the
stationary
arc
-
ing
contacts
at
a
point
measured
in
line
with
the
break
between
the
con
-
tact
stop
and
the
contact
pivot
block
.
Push
the
contact
backward
until
di
-
mension
MBH
recorded
in
item
2
is
reached
.
The
scale
should
then
be
read
.
4
.
If
the
pressure
is
not
within
the
requirements
listed
on
TABLE
I
,
re
-
fer
to
the
section
of
these
instructions
dealing
with
ADJUSTING
CONTACT
WIPE
AND
PRESSURE
.
travel
of
the
contacts
.
Flexible
braid
leads
(
5
)
shunt
the
pivot
pin
to
prevent
possible
pitting
at
the
pivot
point
when
interrupting
high
currents
.
On
later
model
breakers
shunting
springs
are
used
in
place
of
braids
.
The
movable
arcing
-
contact
assem
-
bly
consists
of
parallel
contact
arms
(
4
)
carried
on
two
movable
pivot
pins
(
8
)
and
(
19
)
.
The
arcing
contacts
in
-
terleave
the
main
contacts
and
pivot
with
them
about
pin
(
19
)
.
This
rela
-
tive
motion
is
obtained
by
linkages
from
the
upper
pin
(
7
)
to
the
breaker
mechanism
.
I
,
Remove
arc
quenchers
(
see
above
)
and
lay
on
sides
on
a
flat
sur
-
face
.
2
.
Remove
hardware
from
one
side
of
arc
quencher
as
indicated
in
Fig
.
5
.
3
.
Remove
bolt
fastening
cap
(
4
)
and
barrier
plate
assembly
.
i
4
.
Barrier
plates
may
now
be
lifted
from
assembly
for
inspection
.
5
.
In
reassembling
,
make
sure
components
are
positioned
so
that
holes
for
self
-
tapping
hardware
are
in
line
.
Do
not
strip
threads
in
compound
by
overstressing
screws
.
The
stationary
main
contact
assem
-
bly
includes
main
and
intermediate
contacts
.
The
inter
mediate
-
contact
surface
extends
beyond
the
main
con
-
tacts
and
will
,
therefore
,
make
before
the
main
contacts
and
break
after
the
main
contacts
.
The
number
of
con
-
tacts
for
each
breaker
rating
is
given
in
Table
I
,
The
movable
main
contacts
pivot
around
a
stationary
pin
(
18
)
,
which
holds
them
to
the
lower
block
.
Motion
is
obtained
from
a
second
pin
(
7
)
,
con
-
nected
by
an
insulated
link
(
12
)
to
the
breaker
mechanism
.
In
addition
to
flexible
braids
shunting
the
current
from
the
contact
directly
to
the
lower
contact
block
,
steel
springs
(
17
)
force
the
contacts
against
the
pins
to
pre
-
vent
pitting
at
the
pivot
point
.
The
movable
main
contact
assembly
also
contains
main
and
intermediate
con
-
tacts
.
POLE
UNIT
ASSEMBLY
(
Fig
*
6
)
NOTE
:
The
text
and
part
iden
-
tification
numbers
contained
in
this
section
apply
to
illustra
-
tions
covering
the
AK
-
50
breaker
.
The
same
text
is
ap
-
plicable
to
the
AK
-
75
and
100
breakers
by
referring
to
Fig
.
7
and
identifying
the
similar
parts
.
These
similar
parts
may
not
,
in
every
case
,
be
iden
-
tified
by
the
same
number
.
Each
pole
unit
assembly
consists
of
a
set
of
arcing
contacts
,
a
set
of
main
contacts
,
the
actuating
linkage
and
the
mounting
base
.
See
Fig
.
8
and
9
,
pole
unit
assemblies
mounted
on
back
frame
assemblies
.
The
stationary
arcing
-
contact
as
-
sembly
consists
of
a
set
of
parallel
contact
fingers
(
2
)
,
pin
(
3
)
,
and
com
-
pression
springs
(
22
)
,
which
provide
continuous
contact
pressure
for
the
full
In
order
to
function
properly
,
a
definite
amount
of
contact
pressure
and
contact
wipe
must
exist
between
the
movable
and
stationary
contacts
.
Courtesy of NationalSwitchgear.com

GE AK-50 Specifications

General

Brand	GE
Model	AK-50
Category	Circuit breakers
Language	English