GE AK-50 - Adjusting Center-Pole Contacts; Adjusting Center-Pole Contact Wipe and Overlap; Adjusting Center-Pole Open Contact Gap; Stationary Contact Replacement

Low
-
voitay
Powtr
Circuit
Breakers
GH
-
74600
NOTE
:
If
the
above
adj
ustment
has
been
made
,
it
i
6
necessary
to
recheck
the
outer
-
pole
wipe
.
IfthiB
is
outside
the
prescribed
limits
,
correct
as
described
in
POLE
UNIT
ASSEMBLY
.
r
»
4
.
If
proper
wipe
cannot
be
obtained
within
the
range
of
the
adjustment
de
-
scribed
above
,
it
will
be
necessary
to
obtain
further
adjustment
by
means
of
the
vertical
shims
(
14
)
provided
for
the
purpose
.
In
order
to
accomplish
this
,
proceed
as
follows
:
l
r
~
r
\
r
*
"
0
^
0
r
*
10
a
.
Separate
the
front
frame
from
the
back
frame
(
see
SEPARATION
OF
FRONT
AND
REAR
FRAMES
)
.
17
16
b
.
Loosen
screw
(
13
)
and
remove
bolt
(
15
)
.
c
.
Remove
vertical
shims
(
14
)
to
decrease
wipe
;
add
to
increase
.
15
d
.
Replace
bolt
(
15
)
and
tighten
screw
(
13
)
.
e
.
Reassemble
front
and
back
frame
.
Ad
jutting
Center
-
pole
Open
Contact
Gap
(
Fig
.
16
)
Improper
open
contact
gap
of
the
center
pole
may
be
adjusted
by
the
following
procedure
.
13
14
6
.
Movable
Contact
7
.
Pin
8
.
Buffer
9
.
Crossbar
10
.
Adjusting
Plate
11
.
Bolt
12
.
Buffer
13
.
Screw
1
.
Springs
2
.
Insulation
3
.
Stationary
Contact
4
.
Pin
5
.
Screw
14
.
Shims
15
.
Bolt
16
.
Pin
17
.
Pin
1
.
Loosen
screw
(
13
)
and
bolt
(
15
)
.
Field
discharge
contacts
(
center
po
/
ej
Adjusting
Conter
-
pole
Contact
Wipe
and
Overlap
(
Fig
.
16
)
Fig
.
16
.
of
the
center
-
pole
contacts
and
the
outer
pole
arcing
contacts
may
be
checked
by
the
following
procedure
:
2
.
If
gap
is
to
be
increased
,
hori
-
zontal
shims
(
14
)
should
be
removed
.
If
it
is
to
be
decreased
,
they
should
be
added
.
Shims
may
be
removed
by
If
measurements
reveal
either
in
-
sliding
them
to
the
front
of
the
breaker
,
correct
center
-
pole
contact
wipe
or
They
are
slotted
for
easy
removal
,
incorrect
overlap
of
contacts
,
adjust
-
(
Effect
of
this
adjustment
on
contact
mentfi
should
be
made
by
the
following
wipe
and
overlap
is
negligible
.
)
procedure
:
1
.
Remove
arc
quenchers
(
see
ARC
QUENCHER
)
.
2
.
Insert
safety
pin
in
push
rod
.
(
See
Fig
.
3
under
MAINTENANCE
.
)
3
.
Tighten
hardware
.
1
.
With
outside
poles
open
,
loosen
adjustment
plate
(
10
)
of
center
pole
on
crossbar
(
9
)
by
freeing
bolt
locking
tab
Contact
Replacement
and
loosening
bolts
(
11
)
.
3
.
Operate
closing
mechanism
with
maintenance
handle
until
arcing
con
-
tacts
of
outer
poles
just
touch
.
r
Stationary
Contacts
(
Fig
.
16
)
2
.
If
center
-
pole
wipe
or
overlapis
to
be
increased
,
move
the
adjustment
plate
to
the
left
;
if
it
is
to
be
decreased
,
move
it
to
the
right
.
1
.
Remove
arc
quencher
(
see
ARC
QUENCHER
)
.
4
.
Measure
distance
between
for
-
ward
edge
of
left
stationary
contact
of
center
pole
and
surface
of
insulation
block
behind
contact
.
2
.
Remove
screw
(
5
)
from
braid
.
3
.
After
proper
adjustment
is
made
,
tighten
adjustment
plate
bolts
until
plate
is
snug
.
Then
tap
adjustment
plate
in
such
a
way
as
to
bring
lower
edge
of
slot
in
plate
to
bear
against
bolt
.
Tighten
bolt
until
lockwasher
is
fully
compressed
.
Then
form
locking
tabs
over
bolt
heads
so
that
bolts
are
3
.
Drift
out
pin
(
4
)
and
remove
con
-
5
.
Continue
to
operate
maintenance
closing
handle
until
center
-
pole
contact
opens
fully
.
tacts
.
4
.
Reassemble
in
reverse
order
with
new
contacts
.
"
3
6
.
Repeat
measurement
described
in
step
4
.
Difference
between
meas
-
5
.
Check
contact
overlap
and
wipe
-
-
V
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