Siemens GMI Series

Overhaul
3
.
Loosen
,
but
do
not
remove
,
bolt
fastening
trunnion
to
the
movable
contact stem
of
the
vacuum
tube
.
An
8
mm
or
a
10
mm
Allen
wrench is
required
.
4
.
Disconnect
insulating
pushrod
at
bell cranks
.
Remove
and
discard
two
0.25
"
X
-
washers
.
Spread
the bell crank
ele
-
ments
and
allow the
push
rod
to
drop
down
.
5
.
Refer
to
Figure
51
,
and
using
the
procedure
shown
to
secure
head and
nut
proceed
to
loosen
the
bolts which
fasten
the
flexible
shunt
clamp
to
the
movable
contact
of
the
tube
.
6
.
Remove the
two
X
-
washers
(
discard
)
fastening
the bell
cranks
to
the trunnion
.
7
.
Loosen
,
but do
not
remove
insulating centering
devices
near
the
movable
contact
end
of
the
vacuum
tube
.
8
.
Remove the bolt
fastening
the trunnion
to
the
end
of
the tube
.
Be certain
to
save
the
washers
,
spacer
,
trunnion
and
hard
-
ware
for
later
use
.
Replacement
of
Vacuum
interrupters
The
following
procedures
are
for
the removal and
replacement
of
the
vacuum
interrupters
.
Note
:
Special
care
needs
to
be
exercised
In
removal
of
hardware
around
the bottom
,
or
movable
contact
end
,
of
the
vacuum
interrupt
-
er
.
The
movable
contact
uses a
metal bellows
assembly
to
maintain the
vacuum
seal
while
still
permitting
up
and
down
motion
of
the
contact
.
This
bellows
assembly
is
rugged
and reliable
,
and is
designed
to
withstand
years
of
vertical
movement
However
,
care
should
be
exercised
in
subjecting
the bellows
to
excessive
torque
during
removal and
replace
-
ment
Twisting
the
bellows
through
careless bolt removal
or
tightening
may
damage
the
vacuum
interrupter
index
of
Figures
and Tables
Vacuum Tube
Family
Continuous
Current
Figure
Pole
Unit
Assembly
1200
and
2000
Amp
1200
Amp
2000
Amp
1200
and
2000
Amp
1200
Amp
2000
and
3000
Amp
VS
12015
VS
10006
VS
10006
VS
25002
VS
10028
VS
10028
48
Note
:
List the order and
location
of
each
flat
and lock washer
.
It
is
critical that
these
spacing
washers be
replaced
in
their
exact
order
upon
reassembly
to
assure
proper
operation
of
the breaker
47
50
48
47
49
9
.
Vacuum
Tube
Stationary
Contact
Disassembly
and
Tube
Removal
.
Breaker
Side
Elevation
(
Typical
)
Tube
Clamp
Fastening
Procedure
Gaging
Procedure
and
Stroke
Adjustments
46
51
Circuit
breakers rated
1200
amp
using
the
VS
12015
or
VS
25002
Interrupters
(
Figure
48
)
.
Using
an
19
mm
socket
and
extension
remove
bolt
fastening
vacuum
tube
stationary
contact to
the
upper
primary
connectors
and
upper
stab
suppoh
.
Save
bolt
washer
and lockwasher
.
Carefully
remove
and
set
aside
the
heavy
copper spacer
connecting
the tube
to
the
upper
primary
bars
.
Handle
with
care
to
maintain
flat
ends
on
the
cylindrical
spacer
.
Circuit
breakers rated
1200
amp
using
the
VS
10006
or
VS
10028
Interrupters
(
Figure
47
)
.
Using
9
/
16
(
and
11
/
16
)
socket
and
backup
wrench
remove
two
3
/
8
fasteners
joining
upper
primary
exten
-
sions
to
the stab
support
.
Rejoin
hardware and
save
with
primary
extensions
for
reuse
.
Using
a
24
mm
socket
and
extension loosen and
remove
hex bolt
joining
the
tubes
stationary
contact to
the
bus
extensions and stab
support
.
Remove
primary
exten
-
sions
and
save
.
Circuit
breakers
rated
2000
amp
using
the
VS
10006
Interrupter
(
Figure
50
)
.
Using
a
24
mm
socket and extension loosen and
remove
hex
bolt
joining
the tubes
stationary
contact to
the
primary
extensions
and stab
support
.
After
removing
the bolt
carefully
remove a
3
/
8
copper
spacer
,
handle
carefully
and
save
protecting
the
flat
contact
surfaces
.
9.1
52
Reference
Tables and Lists
Recommended
Tools
Fastener
Torque
Limits
Table
6
Table
7
Preparation
Identify
tube
family
and breaker continuous
current
rating
.
The
tube
will
have
an
identifying
nameplate
showing
the
family
designation
and the continuous
current
requirement
can
be
taken
from
the breaker
s
rating
label
.
Check
the
"
Index
of
Figures
"
to
find
the
appropriate
side
elevation
picture
of
the breaker
pole
unit
assembly
,
Confirm
that
the
figure
applies
by
comparing
the
figure
carefully
to
the
breaker
.
Read
through
the
replacement
procedures
,
noting
recom
-
mended tools
,
gaging
requirements
and
torquing
limits
,
etc
.
Vacuum
Tube
Removal
1
.
Make
provision
to
save
and retain hardware
.
Rejoin
fastener
parts
(
bolts
,
nuts
,
washers
,
lockwashers
,
etc
.
)
as
they
are
removed
.
Save
in
an
appropriate
container
.
2
.
Remove
interphase
and
outer
barriers
as
required
.
9.2
9.3
31
Courtesy of NationalSwitchgear.com