GE AM-4.16-250-6 - Page 24

GEI
-
88761
Magne
-
blast
Circuit
Breaker
E
.
Contact
Arm
Assembly
(
8
,
10
,
12
,
14
,
Figure
23
)
.
1
.
Remove
connection
bar
(
15
)
.
2
.
Disassemble
hinge
pin
(
7
)
,
cup
bearing
(
6
)
,
and
operating
rod
pm
(
4
)
noting
quantity
and
location
of
any
washers
and
spacers
used
in
assemblies
.
3
.
The
contact
arm
assembly
including
the
piston
assembly
(
13
)
can
now
be
re
-
moved
.
4
.
When
reassembling
,
first
insert
piston
tube
assembly
(
13
)
into
the booster
cylinder
and
reassemble
the
cup
bear
-
ing
,
making
sure
the
silvered
contact
washers
between
the
bushing
and
con
-
tact
arms
(
both
sides
)
are
in
place
.
5
.
Reassemble
operating
rod
pin
(
4
)
and
connection bar
(
15
)
.
F
.
After
disassembly
and
reassembly
of
any
contacts
,
check
all
contact
adjustments
as
described under
ADJUSTMENTS
.
13
-
14
©
15
m
-
©
BUSHINGS
IMPORTANT
:
DO NOT
REMOVE
ALL
SIX
BUSHINGS
AT
ONCE
.
The
bushings
have been
carefully aligned
with
the
breaker
frame
,
during
assembly
at
the
factory
,
and
it
is
important
that
this
alignment
be
maintained
to
insure
interchange
-
ability
of
the breakers
in
the metal
-
clad
units
.
It
is
,
therefore
,
recommended
that
the
bushings
be
removed and
reassembled
one
at
a
time
.
Also
,
before
removing
any
one
bushing
,
measure
the
dis
-
tance
from
that
particular
bushing
to
adjacent
bushings
in
both
directions
,
so
that
it
may
be
reinstalled
in
the
same
location
.
Figure
23
.
(
8039588
)
Contact
Assembly
1
.
Front
Bushing
2
.
Contact
Springs
3
.
Stationary
Primary
Contacts
4
.
Operating
Rod
Pin
5
.
Buffer
6
.
Cup
Bearing
7
.
Hinge
Pin
8
.
Contact
Arm
9
.
Throat
Barrier
10
.
Movable
Primary
Contacts
11
.
Assembly
Bolts
12
.
Assembly
Bolts
13
.
Piston
Assembly
14
.
Movable
Arcing
Contact
15
.
Connection
Bar
However
,
it
is
possible
to
remove
and
re
-
assemble
three
bushings
at
one
time
.
If
this
is
preferred
,
alignment
of
the
bushings
may
be
accomplished
by placing
the
breaker
in
a
de
-
energized
spare
metal
-
clad
unit
before
tightening
the
bushing
mounting
bolts
.
This
must
be done
before the
interrupters
are
reinstalled
.
To
replace
the
bushing
,
proceed
as
follows
:
Rear
Bushing
1
.
Open
the
breaker
and
remove
the box
barrier
and
interrupters
as
already
de
-
scribed
.
2
.
Pry
contact
arms
(
8
)
apart
enough
to
disengage
pivot pins
of
piston
assembly
(
13
)
allowing
piston
to
drop
down
into
its
booster
cylinder
.
3
.
Rotate
the
two
parts
of
the
contact
arm
assembly
away
from
each
other
so as
-
sembly
bolts
(
11
)
are
accessible
and
movable
primary
contacts
(
10
)
can
be
removed
.
4
.
Reassemble
in
reverse
order
.
Remove
the
upper
and
lower
horizontal
barriers
(
18
and
20
)
Figure
8
.
Remove
the
four
bolts
at
the
mounting
flange
of
the
rear
bushing
being
removed
and lower the
bushing
assembly
.
NOTE
:
Shims
may
be
found
between the
breaker
mounting
plate
and
the
bushing
2
.
3
.
24
Courtesy of store.ips.us