Allis-Chalmers LA 3000 User manual

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ALUS
-
CHALMERS
INSTRUCTION
BOOK
\
r
AIR
CIRCUIT
BREAKER
TYPE
LA
3000
&
LA
*
>
000
BWX
-
6670
-
1
APRIL
1967
)
(
y
Courtesy of NationalSwitchgear.com

ALLIS
-
CHALMERS
INDEX
TO
INSTRUCTION
BOOK
COVERING
TYPE
LA
-
3000
&
LA
-
4000
CIRCUIT
BREAKERS
SECTION
I
.
GENERAL
INFORMATION
A
.
INTRODUCTION
B
.
WARRANTY
C
.
RECEIVING
AND
INSPECTION
FOR
DAMAGE
D
.
STORAGE
E
.
CAUTIONS
TO
BE
OBSERVED
F
.
INSTALLATION
G
.
MAINTENANCE
H
.
RENEWAL
PARTS
SECTION
II
OPERATING
MECHANISM
A
.
DESCRIPTION
AND
FUNCTION
1
.
STORED
-
ENERGY
MECHANISM
2
.
CLOSING
MECHANISM
MAINTENANCE
CLOSING
RACKING
MECHANISM
AND
DRAWOUT
INTERLOCK
CONTROL
MAINTENANCE
AND
ADJUSTMENT
LUBRICATION
B
.
C
.
D
,
E
.
F
.
SECTION
III
,
CONTACT
STRUCTURE
A
,
DESCRIPTION
AND
FUNCTION
B
.
MAINTENANCE
,
ADJUSTMENT
AND
REPLACEMENT
*
v
>
SECTION
IV
.
STATIC
OVERCURRENT
TRIP
DEVICE
A
.
INTRODUCTION
B
.
DESCRIPTION
SELECTION
OF
SETTINGS
MAINTENANCE
AND
TESTING
RELEASE
MAGNET
1
,
2
.
3
.
V
Courtesy of NationalSwitchgear.com

ALLIS
-
CHALMERS
LIST
OF
ILLUSTRATIONS
COVERING
ALLIS
-
CHALMERS
TYPE
LA
-
3000
&
LA
-
4000
LOW
VOLTAGE
AIR
CIRCUIT
BREAKER
AND
AUXILIARY
EQUIPMENT
FIGURE
NO
,
DESCRIPTION
BREAKER
OUTLINE
1
A
BREAKER
OUTLINE
2
OPERATING
MECHANISM
OPERATING
MECHANISM
(
SCHEMATIC
)
3
,
4
&
,
5
6
PANEL
ASSEMBLY
6
A
PANEL
ASSEMBLY
WIRING
DIAGRAM
7
8
LIMIT
SWITCH
TYPICAL
STATIC
OVERCURRENT
TRIP
DEVICES
9
(
TYPICAL
BREAKER
RATING
PLATE
AND
CURRENT
TRANSFORMERS
9
A
SHAFT
LOCKS
AND
CALIBRATING
MARKS
FOR
STATIC
TRIP
DEVICES
9
B
PORTABLE
TEST
SET
FOR
STATIC
TRIP
DEVICES
9
C
TYPICAL
TRIP
CURVE
(
SELECTIVE
STATIC
TRIP
)
TYPICAL
TRIP
CURVE
(
DUAL
STATIC
TRIP
)
9
D
9
E
9
F
CONNECTIONS
FOR
FUNCTION
TEST
10
RELEASE
MAGNET
12
SECONDARY
DISCONNECT
13
AUXILIARY
SWITCH
14
SHUNT
TRIP
DEVICE
BELL
ALARM
(
MANUAL
RESET
)
BELL
ALARM
(
ELECTRICAL
RESET
)
15
15
A
16
UNDERVOLTAGE
DEVICE
Courtesy of NationalSwitchgear.com

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-
CHALMERS
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RELEASE
SOLENOID
18
,
V
RELAY
19
SHUNT
TRIP
20
.
TRIP
LOCKOUT
21
.
STORED
-
ENERGY
MOTOR
22
GROUNDING
FINGER
23
UNDERVOLTAGE
(
ATTACHMENT
)
24
.
LATCH
INTERLOCK
COVER
TERMINAL
BLOCK
LIMIT
SWITCH
BREAKER NAMEPLATE
PHASE
BARRIER
ARC
CHUTE
PRIMARY
DISCONNECTS
RELEASE
MAGNET
9
.
MANUAL
TRIP
BUTTON
INTERLOCK
BUTTON
AUXILIARY
SWITCH
BELL ALARM
(
ATTACHMENT
)
SECONDARY
DISCONNECTS
MECHANICAL
CLOSING
BUTTON
POWER
CHARCING SWITCH
STATIC
O
.
C
.
TRIP
DEVICE
2
.
10
.
II
.
3
.
4
.
12
.
5
.
13
.
6
.
14
.
7
.
15
.
8
.
16
.
FIG
.
I
TYPICAL
LA
-
3000
BREAKER
OUTLINE
72
-
440
-
008
-
401
MARCH
15
,
1967
Courtesy of NationalSwitchgear.com

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CHALMERS
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MANUAL
TRIP
DUTTON
2
.
INTERLOCK
BUTTON
3
.
AUXILIARY
SWITCH
4
.
BELL ALARM
(
ATTACHMENT
)
5
.
SECONDARY
DISCONNECTS
6
.
MECHANICAL
CLOSING
BUTTON
7
.
POWER
CHARGING
SWITCH
B
.
STATIC
O
.
C
.
TRIP
DEVICE
IT
RELEASE
SOLENOID
ft
V
RELAY
ft
SHUNT
rm
2
Q
TR
*
LOCKOUT
21
.
STORED
-
ENERGY
MOTOR
22
GROUNDING
FINGER
23
UNOERVOLTAGE
(
ATTACHMENT
)
24
LATCH
INTERLOCK
9
.
COVER
10
TERMINAL
BLOCK
II
.
LIMIT
SWITCH
12
BREAKER
NAMEPLATE
13
.
PHASE
BARRIER
14
.
ARC CHUTE
15
.
PRIMARY
DISCONNECTS
16
.
RELEASE
MAGNET
FIG
.
IA
TYPICAL
LA
-
4000
BREAKER
OUTLINE
72
-
440
-
009
-
401
MARCH
15
,
1967
Courtesy of NationalSwitchgear.com

INSTRUCTIONS
FOR
THE
INSTALLATION
AND
OPERATION
OF
ALLIS
-
CHALMERS
TYPE
"
LA
"
LOW
VOLTAGE
AIR
CIRCUIT
BREAKERS
AND
AUXILIARY
EQUIPMENT
SECTION
|
.
INSTALLATION
AND
INSPECTION
A
.
INTRODUCTI
ON
The
type
"
LA
"
air
circuit
breakers
may
be
furnished
for
mounting
in
any
one
of
three
ways
.
They
may
be
used
in
metal
enclosed
switchgear
of
the
drawout
type
,
in
individual
enclosures
(
pullout
type
)
,
or
for
stationary
mounting
in
a
customer
’
s
own
enclosing
case
or
switch
-
board
.
All
"
LA
"
breakers
are
completely
assembled
,
tested
,
and
calibrated
at
the
factory
in
a
vertical
position
and
must
be
so
Installed
to
operate
properly
.
Customer
'
s
primary
connections
should
be
adequately
braced
against
the
effects
of
short
circuit
currents
to
prevent
overstressing
the
breaker
terminals
.
1
!
B
,
WARRANTY
A
1
11
s
-
Cha
Inters
"
LA
"
air
circuit
breakers
are
warranted
to
be
free
of
defects
in
material
and
workmanship
for
a
period
of
one
year
after
delivery
to
the
original
purchaser
.
This
warranty
is
limited
to
the
furnishing
of
any
part
which
,
to
our
satisfaction
,
has
been
proven
defective
,
,
A
)
1
is
-
ChaImers
will
not
in
any
case
assume
responsibility
for
allied
equip
-
ment
of
any
kind
.
C
„
RECEIVING
AND
INSPECTION
FOR
DAMAGE
Immediately
upon
receipt
of
this
equipment
,
carefully
remove
all
packing
traces
and
examine
parts
,
checking
them
against
the
packing
list
and
noting
any
damage
Incurred
in
transit
.
If
such
Is
disclosed
,
a
damage
claim
should
be
filed
at
once
with
the
transportation
company
and
Al
1
is
-
Chalmers
notified
.
J
D
.
CAUTIONS
TO
BE
OBSERVED
IN
THE
INSTALLATION
AND
OPERATION
OF
"
LA
"
CIRCUIT
BREAKERS
READ
INSTRUCTION
BOOK
before
installing
or
making
any
changes
or
adjustments
on
the
breaker
.
As
the
closing
springs
on
stored
-
energy
breakers
may
be
charged
in
either
the
breaker
open
or
closed
position
,
extreme
care
should
be
taken
to
discharge
the
springs
before
working
on
the
breaker
.
Check
current
ratings
and
serial
numbers
against
single
line
diagram
to
assure
that
breakers
are
properly
located
in
switchgear
at
installation
.
1
.
2
„
3
.
4
.
Check
the
alignment
of
the
secondary
disconnect
fingers
to
ensure
against
misalignment
due
to
possible
distortion
of
fingers
during
shipment
and
handling
.
Once
the
breaker
is
energized
,
it
should
not
be
touched
,
except
for
operating
,
since
most
of
the
component
parts
are
also
energized
.
5
»
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)
Courtesy of NationalSwitchgear.com

.
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•
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•
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E
,
INSTALLATION
The
"
LA
"
air
circuit
breaker
is
completely
adjusted
,
tested
,
and
inspected
at
the
factory
before
shipment
,
but
careful
check
should
be
made
to
be
certain
that
shipment
or
storage
has
not
resulted
in
damage
or
change
of
adjustment
.
Circuit
breakers
should
be
installed
in
a
clean
,
dry
,
we
1
!
-
ventiIated
place
in
which
the
atmosphere
is
free
from
destructive
acid
or
alkali
fumes
.
Stationary
type
'
.
breakers
should
be
mounted
high
enough
to
prevent
injury
to
personnel
either
from
circuit
•
Interruption
or
from
moving
parts
during
automatic
opening
of
the
breaker
.
A
!
iow
sufficient
space
to
permit
access
for
cleaning
and
inspection
and
adequate
clearance
to
insulating
barrier
above
the
breaker
to
prevent
,
damage
from
arcing
during
interruption
.
Before
installing
,
make
certain
that
the
breaker
contacts
are
in
the
open
position
,
1
»
After
the
breaker
is
installed
in
position
,
close
It
manually
by
the
maintenance
closing
method
(
See
Sections
li
and
III
)
to
check
proper
•
functioning
of
the
mechanism
and
contacts
,
(
CAUTION
;
MAKE
SURE
CIRCUIT
IS
NOT
ENERGIZED
)
,
During
the
closing
operation
,
observe
that
the
contacts
move
freely
without
interference
or
rubbing
between
movable
arcing
contacts
and
parts
of
the
arc
chutes
.
Then
refer
to
Section
II
of
the
Instruction
Book
for
a
detailed
description
of
the
circuit
breaker
operating
characteristics
before
putting
the
breaker
in
service
.
2
.
Trip
units
and
accessory
devices
should
receive
a
thorough
check
prior
to
placing
the
breaker
in
service
to
be
certain
that
adjustments
are
proper
and
parts
are
not
damaged
.
Cubicle
-
mounted
breakers
of
the
drawout
type
are
equipped
with
a
drawout
interlock
to
prevent
movement
of
a
closed
breaker
into
or
out
of
the
connection
position
.
See
Section
II
of
the
Instruction
Book
for
a
description
of
the
interlock
.
Its
operation
should
be
checked
before
the
breaker
Is
energized
.
Upon
completion
of
the
installation
inspection
,
the
breaker
is
ready
to
be
energized
after
the
control
wiring
is
checked
and
the
Insula
-
tion
tested
.
3
.
4
.
F
.
STORAGE
When
breakers
are
not
to
be
put
into
immediate
us
$
.
,
they
should
be
wrapped
or
covered
with
a
non
-
absorbent
material
to
provide
-
protection
from
plaster
,
concrete
dust
or
other
foreign
matter
.
Breakers
should
not
be
exposed
to
the
action
of
corrosive
gases
or
moisture
.
In
areas
of
high
humidity
or
temperature
fluctuations
,
space
heaters
or
the
equivalent
should
be
provided
,
G
<>
MAINTENANCE
Occasional
checking
and
cleaning
of
the
breaker
will
promote
long
and
trouble
-
free
service
.
A
periodic
Inspection
and
servicing
at
least
every
six
months
should
be
included
In
the
breaker
maintenance
routine
.
If
the
circuit
breaker
Is
not
operated
during
extended
periods
,
the
breaker
should
,
not
remain
in
either
the
closed
or
open
position
any
longer
than
six
months
.
Maintenance
opening
and
closing
operations
should
be
made
to
ensure
freedom
of
movement
of
all
parts
.
H
.
RENEWAL
TARTS
When
ordering
renewal
parts
,
specify
the
complete
name
-
plate
data
including
breaker
serial
number
.
“
2
*
*
Courtesy of NationalSwitchgear.com

*
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(
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LATCH
FIG
.
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TYPICAL
OPERATING
MECHANISM
,
3
«
;
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CONNECTING
ROD
3
S &
V
>
JAN
.
8
,
1964
71
-
340
*
331
*
401
Courtesy of NationalSwitchgear.com

5
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*
CHALMERS
/
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MOVABLE
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UNIT
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PLUNGER
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|
3
‘
SCREW
-
STOREDiENERGY
SPRINGS
16
^
-
FIXED
CENTER
-
MOVABLE
CENTER
FIG
.
3
CLOSED
POSITION
O
31
:
»
LATCH
TRIP
SHAFT
ZI
FIG
.
4
TRIP
-
FREE
POSITION
FIG
.
5
OPEN
POSITION
TYPE
"
LA
"
OPERATING
MECHANISM
v
Tt
«
440
-
184
-
401
AUGUST
30
,
1963
{
li
Courtesy of NationalSwitchgear.com

SECTION
I
1
.
OPERATING
MECHANISM
The
operating
mechanism
is
the
medium
A
,
DESCRIPTION
AND
FUNCTION
used
to
transmit
power
from
the
stored
-
energy
closing
springs
to
the
contact
structure
to
close
the
breaker
.
Cubicle
mounted
breakers
of
the
drawout
type
are
provided
with
the
motivating
means
to
rack
the
breaker
into
and
out
of
the
cubicle
compartment
.
A
maintenance
closing
,
link
is
furnished
to
manually
close
the
breaker
for
inspection
prior
to
Installation
and
for
maintenance
inspection
.
A
double
-
toggle
,
trip
-
free
operating
mechanism
is
used
}
that
is
,
the
breaker
contacts
are
free
to
open
at
any
time
,
if
required
,
regardless
of
the
position
of
the
mechanism
or
the
force
being
applied
.
For
descriptive
purposes
the
operating
mechanism
can
be
divided
into
two
groups
-
the
stored
-
energy
mechanism
and
the
closing
mechanism
.
NOTE
:
In
references
such
as
(
1
-
7
)
»
the
first
number
indicates
the
figure
and
the
second
number
the
item
.
1
.
Stored
-
Energy
Mechanism
Refer
to
Figures
3
»
4
and
5
«
Figure
4
shows
the
stored
-
energy
springs
in
the
discharged
position
.
On
electrically
operated
breakers
,
energization
of
the
motor
by
actuation
of
the
power
charging
switch
(
1
-
7
)
(
1
A
—
7
)
causes
the
motor
to
rotate
pinion
shaft
(
9
)
to
drive
gear
(
10
)
*
This
gear
is
provided
with
a
driving
pin
(
12
)
positioned
to
engage
with
a
corresponding
pin
(
II
)
on
eccentric
(
13
)
.
The
eccentric
is
revolved
clockwise
about
fixed
center
"
A
"
driving
the
connecting
rod
(
14
)
to
the
right
.
The
motion
of
the
connecting
rod
to
the
right
compresses
the
pair
of
stored
-
energy
springs
(
16
)
that
function
as
a
unit
through
links
(
15
)
and
bar
(
34
)
,
At
the
instant
the
springs
are
fully
charged
,
latch
roll
(
18
)
affixed
to
connecting
rod
(
14
)
engages
prop
latch
(
20
)
thus
holding
the
fully
charged
springs
latched
and
ready
to
be
discharged
to
close
the
breaker
either
by
manual
release
of
the
prop
through
mechanical
closing
button
(
1
-
6
)
(
1
A
-
6
)
,
or
by
electrical
release
through
the
solenoid
release
plunger
,
To
guard
against
accidental
overloading
of
the
charging
system
,
gear
(
10
)
that
is
driven
by
the
pinion
shaft
(
9
)
is
shaped
to
disengage
from
the
pinion
shaft
at
the
fully
charged
position
of
the
stored
-
energy
springs
.
This
disengagement
is
accomplished
by
the
removal
of
a
segment
of
the
teeth
from
the
periphery
of
the
gear
.
Flexible
teeth
are
provided
at
the
end
of
the
open
segment
to
facilitate
re
-
engagement
.
(
See
Figure
2
.
)
-
-
>
«
‘
*
*
•
3
“
Courtesy of NationalSwitchgear.com

2
•
Closing
Mechanism
Figure
5
shows
the
mechanism
in
the
open
position
with
the
stored
-
energy
springs
charged
.
The
stored
energy
closing
force
is
released
either
manually
by
depressing
mechanical
closing
button
or
electri
-
cally
by
actuation
of
the
solenoid
release
plunger
.
In
either
case
,
prop
latch
(
20
)
is
rotated
clockwise
to
release
the
connecting
rod
The
connecting
rod
is
attached
to
the
closing
springs
(
16
)
through
link
(
15
)
and
bar
(
3
*
0
and
to
the
bell
crank
(
17
)
by
pin
(
21
)
.
Release
of
the
prop
latch
permits
the
closing
springs
to
move
the
connecting
rod
clockwise
to
the
left
about
fixed
center
"
A
"
and
the
bell
crank
clockwise
about
fixed
center
"
B
’
1
,
Clockwise
rotation
of
the
bell
crank
drives
link
(
22
)
to
rotate
closing
cam
(
23
)
which
acts
against
toggle
rolls
(
24
)
moving
the
toggle
linkage
to
the
right
about
releasable
center
"
C
"
thus
closing
breaker
contacts
.
When
the
full
closed
position
is
reached
,
the
toggle
linkage
is
propped
over
center
against
the
toggle
stop
(
25
)
and
is
supported
through
toggle
latch
(
26
)
,
trip
latch
(
27
)
and
trip
shaft
(
28
)
as
shown
in
Figure
3
*
The
closing
cam
will
remain
in
the
up
,
or
closed
position
until
the
closing
springs
are
charged
.
Charging
of
the
closing
springs
will
rotate
bell
crank
in
the
counterclock
-
wise
direction
thereby
drawing
the
closing
cam
down
into
position
for
another
closure
.
Opening
of
the
breaker
contacts
is
accomplished
by
the
release
of
trip
latch
(
27
)
.
Trip
shaft
(
28
)
is
rotated
counterclockwise
by
action
of
the
various
trip
devices
or
the
manual
trip
button
.
This
rotation
of
the
trip
shaft
permits
trip
latch
(
27
)
to
rotate
counterclockwise
about
fixed
center
"
0
"
thus
toggle
latch
(
26
)
f
s
released
and
permitted
to
rotate
clockwise
about
center
"
E
"
,
Releasable
center
"
C
"
Is
now
free
to
rotate
with
the
toggle
latch
permitting
the
force
of
the
stationary
main
contact
spring
as
well
as
the
opening
springs
to
move
cranks
(
29
)
,
(
4
o
)
clockwise
to
collapse
the
toggle
linkage
as
shown
in
Figure
5
,
The
rotation
of
cranks
(
29
)
,
(
4
o
)
and
movement
of
link
(
30
)
to
the
left
,
thereby
opens
the
breaker
contacts
.
The
resetting
sequence
of
the
trip
latch
,
toggle
latch
and
toggle
linkage
is
entirely
dependent
on
the
position
of
the
stored
energy
springs
.
With
the
springs
charged
,
the
latches
and
toggle
mechanism
will
immediately
reset
as
shown
in
Figure
5
.
With
the
springs
discharged
,
and
the
breaker
open
,
the
closing
cam
will
hold
the
toggle
mechanism
trip
-
free
as
shown
In
Figure
4
until
the
charging
sequence
is
started
at
which
time
the
closing
cam
will
be
withdrawn
permitting
the
toggles
and
latches
to
reset
.
(
14
)
.
Figure
4
shows
the
mechanism
in
the
trip
-
free
position
.
When
latches
(
27
)
and
(
26
)
are
released
,
center
"
C
"
is
not
restrained
as
in
normal
closing
operation
,
but
now
is
released
to
pivot
about
pin
"
E
"
as
a
center
.
Thus
when
closing
energy
is
delivered
to
the
toggle
linkage
through
the
closing
cam
,
the
toggle
latch
(
26
)
rotates
clockwise
about
the
new
center
"
E
"
permitting
the
closing
Courtesy of NationalSwitchgear.com

f
cam
to
go
through
its
complete
cycle
without
moving
link
(
30
)
and
the
breaker
contacts
,
therefore
,
will
not
close
.
This
action
can
take
place
during
any
part
of
the
closing
stroke
,
causing
movable
contacts
(
33
)
to
immediately
return
to
the
open
position
even
though
the
stored
energy
springs
are
acting
to
close
the
mechanism
.
During
inspection
prior
to
installation
and
for
subsequent
routine
maintenance
inspections
,
the
breaker
may
be
closed
manua
11
y
as
foilows
s
Refer
to
Figure
5
„
1
»
Place
the
breaker
on
the
floor
or
other
firm
base
,
(
Do
not
use
this
method
of
operation
while the
breaker
Is
in
the
switchgear
cubicle
or on
the
extension
rails
)
,
2
,
Remove
the
front
sheet
-
metal
cover
,
3
,
With
the
switchgear
operating
crank
or
a
3
/
8
"
square
-
socket
speeder
wrench
,
rotate
screw
(
43
)
to
place
crank
(
4
l
)
and
arm
(
42
)
approximately
in
the
position
shown
in
Figure
5
»
4
,
insert
manual
maintenance
closing
link
(
19
)
with
the
"
U
"
shaped
section
over
pin
(
44
)
in
center
crank
(
40
)
,
Align
the
hole
in
the
maintenance
closing
link
with
the
holes
In
arm
(
42
)
and
insert
the
pin
that is attached
to
the
maintenance
closing
link
,
5
,
As
the
closing
mechanism is
now
linked
to
screw
(
43
)
,
clockwise
rotation
of
the
operating
crank
will
slowly
move
the main
contacts
to
the
contact
touch
position
,
6
,
Reversal
of
operating
crank
rotation
to
counterclockwise
will
slowly
return
the
contacts to
the
open
position
,
7
,
Replace
the
front
sheet
-
metal
cover
after
removing
maintenance
closing
11
nk
.
B
.
MAINTENANCE
CLOSING
r
r
*
I
During
maintenance
closing
operation
,
observe
that
the
contacts
move
freely
without
interference
or
rubbing
between
movable
arcing
contact
(
6
-
1
)
(
6
A
-
1
)
and
parts
of
the
arc
chutes
(
1
—
14
)
(
1
A
-
14
)
.
Cubicle
mounted
breakers
of
the
drawout
type
Include
as
integral
parts
the
motivating
means
to
rack
the
breaker
in
and
out
of
the cubicle
compartment
,
the drawout
position
indicator
and the
drawout
trip
interlock
.
Refer
to
Figures
1
,
1
A
and
2
,
Manual
trip
button
(
2
-
29
)
,
0
”
!
)
,
(
1
A
-
1
)
,
which
is
an
essential
part
of
the drawout
and
interlock
linkage
,
performs
a
dual
function
:
C
,
RACKING
MECHANISM
AND
DRAWOUT
INTERLOCK
C
.
-
5
»
Courtesy of NationalSwitchgear.com

1
.
Within
the
limits
of
movement
in
the
large
slot
,
actuation
of
the
button
trips
the
breaker
by
means
of
engagement
of
trip
rod
(
2
-
43
)
with
angle
(
2
-
45
)
.
and
releases
trip
latch
(
2
-
46
)
By
raising
knob
(
1
-
2
)(
1
A
-
2
)
,
the
stop
Is
removed
from
the
large
slot
in
trip
button
(
2
-
29
)
(
1
-
1
)
(
1
A
-
1
)
and
the
button
may
then
be
pushed
in
to
the
limit
of
Its
travel
.
(
Lowering
the
knob
will
place
the
stop
in
the
narrow
slot
to
hold the button
in
this
position
.
)
Through
interlock
crank
(
2
-
42
)
,
link
(
2
-
37
)
and
eye
end
(
2
-
38
)
,
the
interlock
latch
(
2
-
39
)
is raised
above
the
fixed
stop
on
the
floor
of
the
cubicle
compartment
.
The
breaker
is then
free
to
be
racked
in
or
out
of
the
cubicle
.
The
necessary
actuation
of
the
manual
trip
button
to
release
the
interlock
latch
prevents
possible
movement
of
a
closed breaker
out
of
the
"
CONNECT
"
,
"
TEST
"
or
"
DISCONNECT
"
position
.
With
the
breaker
in
position
on
the rail
extensions
,
the
following
sequence
should
be
used
to
rack
the
breaker into
the
fully
connected
position
,
1
,
Raise
the
drawout
release
stop
knob
(
1
-
2
)
(
1
A
-
2
)
,
push
in
the
manual
trip
button
(
2
-
29
)
(
1
-
1
)
(
1
A
-
1
)
to
its
full
travel
,
and
lock
the
trip
button
in
this
position
by
resetting
the
drawout
release
stop
in
the
last
slot
in
the
trip
button
.
With
the
trip
button
in
this
position
,
interlock
latch
(
2
-
39
)
is
raised
permitting
movement
of
the
interlock
and
breaker
past
the
fixed
stop
on
the
floor of
the
cubicle
compartment
.
2
,
Move
slide
near
the
top
of
the sheet
-
metal
cover
to
the
right
to
uncover
the
square
end
of
screw
(
2
-
19
)
,
3
,
With
the
switchgear
operating
crank
,
rotate
screw
(
2
-
19
)
to
position
racking
cranks
(
2
-
53
)
approximately
as
shown
in
Figure
2
.
Move the
breaker
along
the
rail extensions
until
the
racking
cranks
engage
the
fixed
pins
in
the cubicle
.
This
rotates
trip
shaft
(
2
-
44
)
counterclockwise
thus
tripping
the
breaker
.
2
.
s
<
i
t
n
i
I
:
i
ft
CAUTION
:
DO
NOT MOVE
BREAKER
BEYOND
THIS
POINT
.
FOLLOW
STEP
4
BELOW
FOR
FURTHER
MOVEMENT
OF
THE
BREAKER
.
Be
certain
that
power
charging
switch
(
2
-
24
)
is
in
the
"
OFF
"
position
.
Counterclockwise
rotation
of
the
operating
crank
will
now
rack
the
breaker
successively
into
the
"
DISCONNECT
"
,
"
TEST
"
,
OR
"
CONNECT
"
post
tions
,
At
each
designated
position
of
"
DISCONNECT
"
,
"
TEST
"
,
and
"
CONNECT
"
the
interlock
latch
(
2
-
39
)
can
be
lowered
into
a
slot
In
the
fixed
stop
on
the
floor
of
the cubicle
compartment
by raising
drawout
release
stop
knob
and
permitting
the manual
trip
button
to
return
to
its
normal
extended
position
.
The
breaker
is
operable
electrically
oniy
in
the
"
TEST
"
and
"
CONNECT
"
positions
.
4
.
nl
^
an
Courtesy of NationalSwitchgear.com

It
may
be
more
convenient
to
raise
the
drawout
release
stop
knob and
permit
the
manual
trip
button
to return
to
Its
normal
extended
position
prior
to
reaching
any
of
the
slots
In
the
fixed
stop
.
The
interlock
latch
will
then
drop
into
position
as
the
breaker
Is
moved
along
the
raiis
,
5
,
To
move
out
of
any
position
,
the
previously
described release
procedure
of
raising
the
drawout
release
stop
knob and
actuating
the
manual
trip
button
is
required
.
6
.
To
withdraw the
breaker
from
the
"
CONNECT
"
position
,
the
drawout
interlock
releasing
procedure
is
the
same
except
that
the
direction
of
rotation
of
the
operating
crank
becomes
clockwise
.
When
the
manual
trip
button
is
in
the extended
position
be
sure
to
return
the
stop
to
the slot
by
lowering
knob
{
1
“
2
)
(
1
A
-
2
)
.
When the
power
charging
switch
(
2
-
24
)
Is
in
the
"
ON
"
position
and
the
breaker
is
in
"
TEST
"
or
"
CONNECT
"
position
,
the
stored
energy
springs
will
be
automati
-
cally
charged
if
the
control
circuit
Is
energized
.
NOTE
;
(
NOTE
;
TO
AVOID
DAMAGE
TO
THE RACKING
MECHANISM
,
DO
NOT
ROTATE
OPERATING
CRANK
UNLESS
THE
INTERLOCK
LATCH
IS
RELEASED
-
AND
DO
NOT
OPERATE BEYOND
THE
LIMITS
OF
"
DISCONNECT
"
OR
"
CONNECT
"
POSITION
.
CAUTION
;
f
The
electrical control
on
the
breaker
Is
designed
to
ensure
complete
operation
and
prevent
repeated
attempts
to
close
(
"
pumping
"
)
.
The
following
is
the
operational
sequence
of
a
typical wiring
diagram
,
Figure
7
»
which
is
shown
with
the stored
-
energy
springs
in
the
discharged
posItion
;
1
.
With
the
three
contacts
-
motor
limit
contact
88
b
,
normally
closed
Y
1
contact
,
and
power
charging
switch
(
N
)
all
closed
,
motor
(
M
)
can
be
energized
,
2
.
Energizing
the
motor
completely
charges
the
stored
-
energy
springs
.
As
the
springs
approach
the
charged
position
,
motor
limit
contact
88
b
opens
and
cuts
off
power
to
the
motor
.
As
88
b
opens
,
88
a
closes
and
sets
up
the
circuit
to
the
spring
release
coil
(
SRC
)
for
a
breaker
closing
operation
.
3
.
Closing
the
control
switch
(
CSC
)
energizes
the
spring
release
coil
discharging
the
energy
in
the
springs
,
As
the breaker
closes
,
the
b
and
88
a
contacts
open
to
cut
off
power
to
the
spring
release
coll
.
The
Y
coil
is
energized
simultaneously
with
the
SRC
,
and
causes
the
Y
1
contact
to
open
the
circuit
to
the
motor
.
Since
the
Y
relay
will
remain
energized
as
long
as
the
control
switch
is
held
closed
,
it
eliminates
"
pumping
"
or
repeated
attempts
to
charge
the
stored
-
energy
springs
„
D
,
CONTROL
*
.
.
_
,
«
*
7
Courtesy of NationalSwitchgear.com

Although
variations
may
be
necessary
or
other
control
elements
added
to
suit
a
specific
application
,
the
basic
arrangement
will
be
as
shown
in
Figure
7
»
E
,
MAINTENANCE
AND
ADJUSTMENT
A
semi
-
annual
inspection
and
servicing
is
usually
sufficient
;
however
,
in
cases
where
unfavorable
atmospheric
conditions
exist
,
more
frequent
inspections
are
recommended
.
In
any
case
,
the
total
number
of
breaker
operations
between
servicing
should
not
exceed
250
,
After
a
severe
overload
interruption
,
the
breaker
should
be
inspected
.
if
the
circuit
breaker
Is
not
operated
during
extended
periods
,
it
should
not
remain
in
either
the
closed
or
open
position
any
longer
than
six
months
.
Maintenance
opening
and
c
1
osing
operations
should
be
made
to
ensure
freedom
of
movement
of
all
parts
.
A
suggested
procedure
to
follow
during
maintenance
inspections
Is
given
.
below
;
1
»
De
-
energize
the
primary
and
control
circuits
,
2
,
Rack
cub
!
cie
-
mounted
breakers
of
the
drawout
type
to
the
disconnected
position
.
3
,
Discharge
stored
-
energy
springs
.
4
,
Remove
arc
chutes
and
examine
for
burned
,
cracked
,
or
broken
parts
,
5
,
Wipe
the
contacts
with
a
clean
cloth
saturated
with
a
non
-
toxic
cleaning
fluid
,
6
,
Replace
badly
burned
or
pitted
contacts
,
7
,
Wipe
all
insulated
parts
with
a
clean
cloth
saturated
with
a
non
-
toxic
cleaning
fluid
.
Bearing
pins
and
other
sliding
or
rotating
surfaces
should
be
cleaned
and
then
coated
with
a
light
film
of
grease
(
BEACON
P
290
or
similar
)
.
(
Silver
plated
current
-
carrying
friction
areas
are
lubricated
with
graphite
.
)
9
.
Operate
the
breaker
manually
In
maintenance
closing
position
to
check
latch
and
linkage
movement
.
10
,
Check
breaker
adjustments
.
The
following
items
are
listed
for
convenience
in
maintaining
the
operating
mechanism
in
good
condition
;
1
,
Trip
Latch
Adjustment
The
trip
latch
(
2
-
46
)
’
should
have
an
engagement
of
3
/
64
"
to
1
/
16
"
,
The
measurement
is
from
the
flat
face
of
the
trip
shaft
(
2
-
44
)
to
the
bottom
Iip
of
the
trip
latch
.
Adjustment
is
obtained
by
positioning
manual
trip
rod
(
2
-
29
)
(
2
-
43
)
against
angle
(
2
-
45
)
on
trip
shaft
.
This
measurement
may
be
checked
by
chalking
the
face
of
the
latch
.
8
-
8
-
Courtesy of NationalSwitchgear.com

;
2
,
Toggle
Latch
Adjustment
The
toggle
latch
stop
clearance
should
measure
.
005
to
.
010
"
.
measurement
is
the
clearance
between
the
adjusting
screw
(
2
-
59
)
and
the
extension
on
toggle
latch
(
2
-
47
)
when
the
breaker
mechanism
is
reset
and
the
toggle
latch
is
biased
against
the
trip
latch
roll
.
Measurement
is
made
with
feeler
gauge
through
hole
In
right
-
hand
side
plate
.
Prop
Latch
Adjustment
The
prop
latch
engagement
should
measure
3
/
16
"
to
1
/
4
"
.
The
measurement
Is
from
the
top
edge
of
the
latch
(
2
-
30
)
to
the
mean
line
of
contact
of
the
eccentric
pin
(
2
-
35
)
«
Adjustment
is
obtained
by
positioning
spacers
on
the
end
of
solenoid
release
(
1
-
15
)
(
IA
-
15
)
plunger
.
Check
this
adjustment
by
operating
the
solenoid
release
electricaliy
.
Limit
Switch
This
switch
is
adjusted
by
turning
the
adjusting
screw
(
8
-
3
)
so
that
the
"
bb
"
contacts
of
the
limit
switch
(
8
-
i
)
open
just
prior
to
the
spring
charge
latch
position
.
The
3
.
4
.
5
.
Motor
Drive
Unit
The
motor
drive
unit
(
2
-
7
)
is
mounted
on
the
operating
mechanism
Shou
1
d
frame
and
held
in
position
by
three
mounting
screws
(
2
-
4
)
.
realignment
of
the
unit
be
necessary
,
add
or
remove
spacers
to
provide
alignment
of
the
motor
shaft
with
the
pinion
(
2
-
9
)
vertically
.
The
motor
shaft
should
also
be
positioned
as
closely
as
possible
to
the
center
of
the
pinion
horizontally
.
(
F
.
LLIBK
)
CAT
!
ON
Lubrication
should
be
a
part
of
the
service
procedure
.
Needle
bearings
are
packed
with
grease
and
should
require
no
further
attention
.
Old
grease
should
be
removed
from
bearing
pins
and
other
rotating
or
sliding
surfaces
,
and
they
should
be
wiped
with
a
thin
film
of
petroleum
-
oiI
-
base
precision
-
equipment
grease
similar
to
BEACON
P
-
290
.
Greasing
should
be
done
with
care
because
excess
grease
tends
to
collect
foreign
matter
which
in
time
may
make
operation
sluggish
and
may
affect
the
dielectric
strength
of
insulating
members
.
i
.
.
.
g
-
Courtesy of NationalSwitchgear.com

y
ARCING
CONTACT
SPRINGS
-
!
3
STATIONARY
ARCING
CONTACT
5
)
—
ARC
RUNNER
MAIN
CONTACT
^
(
2
FINGERS
'
—
SCREW
MOVABLE
ARCING
CONTACT
I
MAIN
CONTACT
SPRINGS
>
INNER
MOVABLE
MAIN
CONTACT
-
SCREW
>
STATIONARY
MAIN
CONTACT BLOCK
PIN
F
OUTER
MOVABLE
MAIN
CONTACT
tC
)
-
SH
!
ELD
tfi
2
SJ
-
PIN
B
PLATE
n
U
J
-
SCREW
HINGE
x
CONTACT
FINGER
—
t
(
7
}
HINGE
24
J
-
SCREW
>
CONTACT
SPRINGS
-
!
56
HINGE
CHANNEL
CONTACT
BLOCK
-
!
15
1
SCREW
-
114
m
BASE
-
l
53
:
o
cis
FIG
.
6
LA
-
3000
BREAKER
PANEL
ASSEMBLY
r
SEPTEMBER
3
»
1963
71
-
440
-
136
-
401
Courtesy of NationalSwitchgear.com

•
>
ARCING
CONTACT
SPRINGS
-
(
3
STATIONARY
ARCING
CONTACT
MAIN
CONTACT
FINGERS
5
)
—
ARC
RUNNER
S
j
-
SCREW
MOVABLE
ARCING
CONTACT
s
7
MAIN
CONTACT
SPRINGS
M
;
i
i
>
u
.
/
_
A
in
P
n
n
u
/
l
!
INNER
MOVABLE
MAIN
CONTACT
T
S
r
-
,
t
'
SCREW
1
ft
>
ripj
~
H
Ml
m
1
STATIONARY
MAIN
CONTACT
BLOCK
nsi
3
Z
r
:
!
]
1
1
n
PIN
-
irf
!
i
h
!
f
u
M
.
.
.
T
:
1
i
li
rr
T
OUTER
MOVABLE
MAIN
CONTACT
I
t
10
I
—
SHIELD
ri
- -
I
fCFOtZu
tfl
n
.
25
)
-
PIN
TOE
ffA
t
+
l
i
Vv
S
V
PLATE
f
\
>
1
n
il
}
-
SCREW
/\
\
/
HINGE
1
i
T
ig
x
a
HINGE
24
-
SCREW
>
I
o
HINGE
CONTACT
BLOCK
-
1
15
CHANNEL
r
©
13
22
SCREW
—
I
14
l
i
BASE
m
o
7
»
m
FIG
.
LA
-
4000
’
’
BREAKER
PANEL
ASSEMBLY
SEPTEMBER
3
,
1963
71
-
440
-
137
-
401
V
/
•
Courtesy of NationalSwitchgear.com

SECTION
111
.
CONTACT
STRUCTURE
_
_ _
_ _
_ _
_
Refer
to
Figures
6
and
6
A
,
The
contact structure
consists
of
main
current
carrying
contacts
and
arcing
contacts
arranged
so
that
contact
make
and
break
is
by
means
of
the
arcing
contacts
.
The
main
contacts
are
not
subjected
to
arcing
.
Arcing
contact
surfaces
are
clad
with
an
arcing
alloy
which
greatly
reduces
mechanical
wear
and
arc
erosion
,
A
positive
wiping
action
of
the
arcing
contacts
prevents
welding
and
sticking
when
interrupting
high
currents
.
Both
the
stationary
and
the
movable
arcing
contacts
have
arc
runners
which
lead
the
arc
away
from
the
contact
surfaces
.
This
prolongs
contact
life
as
well
as
aiding
arc
interruption
.
The
main
ctirrent
carrying
contacts
are
silver
plated
and
have
a
positive
wiping
action
.
This
ensures
high
conductivity
and
maintains
the
current
carrying
areas
clean
,
smooth
and
free from
pitting
or
hammering
.
When
the
main
contacts
make
,
the
first
point
of
contact
is
at
the
lower
end
of
contact
finger
(
2
)
,
Further
motion
causes
this
contact
finger
to
rotate
in
its
socket
,
causing
the
contact
point
to
move
up
toward
the
"
knee
"
of
the
contact
and
separating
the
initial
contact
point
.
When
the breaker
is
called
upon
to
interrupt
a
current
,
the main
contacts
(
22
)
,
(
20
)
and
(
2
)
separate
,
transferring
the
current
to
the
arcing
contacts
(
1
)
and
(
4
)
without
arcing
.
When
the
arcing
contacts
part
,
an
arc
is
drawn
between
the
contact
surfaces
.
Due
to
the
inherent
magnetic
and
thermal
effects
of
the
arc
,
It
will
rapidly
move
upwards
along
the
arc
runner
and
into
the
arc
chute
(
1
-
14
)
,
(
IA
-
I
4
)
where
it
is
extinguished
.
A
.
DESCRIPTION
AND
FUNCTION
B
.
MAINTENANCE
.
ADJUSTMENT
AND
REPLACEMENT
,
A
semi
-
annual
inspection
and
servicing
is
usually
sufficient
;
however
,
in
cases
where
unfavorable
atmospheric
conditions
exist
,
more
frequent
Inspections
are
recommended
.
In
any
case
,
the
total
number
of
breaker
operations
betweenft
,
servIcing
should
not
exceed
250
,
The
following
items
are
listed
for
convenience
in
maintaining
the
contact
structure
in
good
condition
:
1
,
Genera
1
Check
main
contacts
for
cleanliness
.
(
They
should
not
be
dressed
,
)
Check
arcing
contacts
for
wear
and
arc
erosion
.
Contacts
should
be
replaced
if
arcing ailoy
shows
indications
of
wearing
through
before
the
next
inspection
.
With
arcing
contacts
(
1
)
and
(
4
)
just
touching
if
a
1
/
8
"
diameter
rod
cannot
be
passed
between
stationary
contact
fingers
(
2
)
and
movable
main
contact
(
20
)
,
(
22
)
,
arcing
contacts
should be
replaced
.
(
,
10
Courtesy of NationalSwitchgear.com

2
.
Contact
Adjustment
The
arcing
contacts
are
connected
to
the
main
contacts
and
as
such
cannot
be
adjusted
independently
of
the
main
contacts
.
The
main
contacts
(
2
o
)
,
(
22
)
are
factory
adjusted
and
should
not
require
any
field
adjustments
unless
parts
have
been
disassembled
.
Adjustment
is
made
by
positioning
connecting
rod
(
2
-
48
)
on
rod
end
(
2
-
58
)
.
The
main
contacts
are
in
proper
adjustment
when
there
is
a
clearance
of
1
/
32
"
to
1
/
16
"
measured
at
each
side
of
the
contact
,
between
the
bottom
of
the
main
contact
finger
(
2
)
and
the
face
of
the
movable
main
contacts
(
20
)
,
(
22
)
with
the
breaker
fully
closed
and
latched
.
Ail
main
contact
fingers
should
be
in
contact
at
the
"
knee
"
of
the
contact
and
open
at
the
bottom
.
Movable
Arc
1
na
Contact
Replacement
The
movable
arcing
contacts
(
1
)
may
be
replaced
after
removing
arc
chutes
by
removing
screw
(
23
)
and
pin
(
21
)
,
After
removal
of
these
two
I
terns
the
movable
arcing
contacts
can
be
lifted
out
and
replaced
.
No
adjust
-
ment
is
required
.
Stationary
Arcing
Contact
Replacement
The
stationary
arc
!
ng
'
contact
(
4
)
'
may
"
be
replaced
,
after
removal
of
arc
chutes
,
merely
by
removal
of
screws
holding
the
retainer
.
Replacement
is
obvious
and
no
adjustment
is
required
.
Movable
Main
Contacts
Replacement
The
movable
main
contacts
1
(
20
)
,
(
22
)
may
be
replaced
,
after
the
removal
of
the
arc
chutes
,
as
follows
:
3
.
4
.
5
«
a
)
Disconnect
rods
from
movable
main
contact
by
removing
pin
from
arm
09
)
.
b
)
Remove
the
four
screws
(
14
)
which
mount
base
(
13
)
on
channel
(
12
)
,
This
will
permit
disassociation
of
the
complete
three
-
phase
contact
structure
,
from
the
breaker
as
a
complete
integral
unit
.
c
)
Remove
screw
(
24
)
and
spring
back
plate
(
26
)
over
roll
pins
(
25
)
.
Rotate
the
movable
main
contact
past
the
hinge
contact
fingers
(
17
)
.
Since
the
hinge
contact
fingers
and
the
main
contacts
are
under
spring
pressure
,
care
must
be
used
so
as
not
to
^
score
or
damage
either
contact
surfaces
.
d
)
Reassemble
by
reversal
of
this
procedure
.
Stationary
Main
Contacts
Replacement
To
remove
the
lower
hinge
contact
block
(
15
)
>
first
remove
the
movable
contact
assembly
(
20
)
,
(
22
)
as
outlined
above
,
then
screws
(
11
)
.
To
remove
stationary
main
contact
block
(
9
)
,
remove
movable
contact
assembly
above
,
then
screws
(
8
)
.
This
will
permit
the
removal
of
the
stationary
main
contact
block
,
stationary
arcing
contact
(
4
)
and
arc
runner
(
5
)
as
an
integral
unit
.
Once
the
above
members
have
been
removed
,
the
contact
fingers
(
2
)
and
(
17
)
can
be
removed
,
cloth
or
other
shield
to
prevent
springs
from
flying
free
,
driver
may
be
used
to
work
springs
and
fingers
to
the
ends
of
the
block
for
removal
.
Be
careful
not
to
raise
nicks
or
burrs
or
otherwise
damage
contact
fingers
.
During
reassembly
of
these
contact
blocks
,
no
adjust
-
ments
are
necessary
.
6
.
Remove
the
contact
fingers
under
a
A
screw
1
1
-
Courtesy of NationalSwitchgear.com