GE ML-14-0 - MAINTENANCE; PERIODIC INSPECTION AND PRECAUTIONS; TRIP-FREE OPERATION

Spring
-
charged Operating
Mechanism
Type
ML
-
14
-
0
GEK
7153
(
21
)
,
Fig
.
9
,
and
the
links
(
41
)
,
Fig
.
10
,
causing
bending
of
the
pin
and
indenta
-
tions
on
the
links
.
When
closing
the
breaker
the
energy
in
the
springs
is
used
and
the
stop
pin
or
links
are
not
damaged
.
it
does
during
a
normal
closing
operation
when
the
motor
is
energized
.
the
opening
operation
,
the
operating
mechanism
is
returned
to
its
normal
position
,
ready
for
closing
.
Manual
tripping
follows
the
same
procedure
except
that
instead
of
energi
-
zing
the
trip
circuit
,
the
manual
trip
lever
(
19
)
,
Fig
.
2
,
is
used
.
If
the
control
house
is
closed
pushing
the
manual
trip
push
button
(
21
)
,
Fig
.
2
,
on
the
surface
of
the
front
door
will
trip
the
breaker
.
The
mechanism
cannot
be
operated
slowly
while
opening
.
m
TRIP
-
FREE
OPERATION
When
testing
the
breaker
the
trip
-
free
operation
should
be
made
by
using
the
breaker
contacts to
energize
the
trip
-
free
circuitry
.
This
more
closely
simulates
a
breaker
closing
against
a
fault
.
(
f
the
trip
coil
is
energized
while
the
breaker
is
closing
,
the
trip
coil
plunger
(
3
)
,
Fig
.
7
,
will
force
the
trip
latch
(
6
)
,
Fig
.
2
,
away
from
the
trip
roller
(
20
)
,
Fig
.
2
,
causing
the
mechanism
linkage
to
collapse
and the
breaker
to
reopen
.
The
closing
cam
(
39
)
,
Fig
.
30
,
will
complete
its
closing
stroke
and
the
springs
will
recharge
as
in
a
normal
closing
operation
.
The
position
of
the
mechanism
linkage
during
its
operation
is
shown
in
Figures
36
,
17
and
18
.
OPENING
OPERATION
An
electrical
opening
operation
is
initiated
by
energizing
the
trip
coil
(
15
)
,
Fig
.
2
.
This
is
accomplished
either
by
actuating
a
remote
trip
circuit
or
by
a
combination
of
relays
and
current
devices
used
to
detect
a
fault
on
the
load
side
of
the breaker
.
When
energizing
the
trip
coil
,
being
closed
without
charging
the
closing
the
trip
plunger
rotates
the
trip
latch
(
6
)
,
Fig
.
2
,
causing
the
operating
mech
-
anism
linkage
to
collapse
.
The
energy
stored
in
the breaker
opening springs
is
the
cam
into
the
undotted
position
thus
released
,
opening
the
breaker
,
shown
in
Fig
.
18
-
since
the
motor
did
not
During
this
operation
,
the
trip
coii
circuit
start
charging
the
closing springs
is
de
-
energized
,
and
upon
completion
of
immediately
upon
closing
the breaker
as
When
the breaker
is
opened
after
springs
,
the
cam
(
39
)
,
Fig
.
10
,
is
in
the
position
of
the dotted
cam
shown
in
Fig
.
18
.
This
is
due
to
the
motor
not
forcing
MAINTENANCE
3
.
Use
the
connection
diagram
accompanying
the
operating
mechanism
in
all
cases
when
testing
and
connecting
the
mech
-
anism
.
4
,
When
making
adjustments
in
the
mechanism
or
breaker
make
certain
that
the
closing
springs
are
blocked
as
described
under
MANUAL
CLOSING
.
PERIODIC INSPECTION
The
operating
mechanism
of
an
oil
circuit
breaker
is
a
very
important
part
and
must
have
regular
systematic
inspec
-
tion
during
which
every
part
is
looked
over
carefully
.
The
frequency
of
inspec
-
tions
should be
determined
by
each
operating
company
on
the
basis
of
the
service
to
which
the
operating
mechanism
is
subjected
.
Operating
experience
will
soon
establish
a
maintenance
schedule
that
will
give
assurance
of
proper
mech
-
anism
condition
,
An
annual
inspection
and
maintenance
program
is
desirable
in
addition
to
-
a
visual
inspection
at
more
frequent
intervals
.
These
inspections
should
be
co
-
ordinated
with
an
inspection
of
the
breaker
parts
for
maximum
convenience
.
Output
crank
to
breaker
-
vertical
operating
rod
shaft
Output
crank
main
shaft
Linkage
to
output
crank
shaft
Cam
follower
roller
shaft
Trip
latch
clearance
adjustment
eccentric
shaft
Trip
latch
roller
shaft
Trip
latch
shaft
Cam
shaft
Closing
latch
shaft
Link
shaft
Stop
pin
Driving
pawl
pin
Driving
link
pin
Guide
block
pin
(
right
side
)
Guide
block
pin
(
left side
)
Driving
eccentric
shaft
Driving
eccentric
to
sprocket
shaft
Latching
and
safety
shaft
Prop
spacer
and
reset
spring
pin
A
.
B
.
C
.
D
.
DO
NOT
WORK
ON
THE
BREAKER
OR
MECHANISM
WHILE
IN
THE
CLOSED
POSI
-
TION
UNLESS
THE
PROP
AND
TRIP
LATCH
HAVE
BEEN
SECURELY
WIRED
QR
BLOCKED TO
PREVENT
ACCIDENTAL
TRIPPING
.
DO
NOT
W O R K
O N
T H E
BREAKER
OR
MECHANISM
WHILE
THE
SPRINGS
ARE
CHARGED
UNLESS
THEY
ARE
SECURED
IN
THAT
POSI
-
TION
BY THE
MAINTENANCE
SPRING
BLOCKING
DEVICE
.
E
.
F
.
G
.
1
H
.
t
1
.
)
J
.
K
.
L
.
M
.
PRECAUTIONS
1
,
Be
sure
that
all
primary
and
secondary
circuits
have been
opened
and
grounded
before
any
inspection
or
maintenance is
attempted
.
2
.
After
any
adjustment
is
made
in
the mechanism
,
operate
manu
-
ally
to
check
the
adjustment
before
operating
electrically
.
N
.
O
.
P
.
R
.
S
.
U
.
5
.
DO
NOT
OPERATE
THE
MANUAL
CLOSE
BUTTON
WHEN
THE
BREAKER
IS
IN
THE
CLOSED
POSITION
.
Shaft
and
Pin
Identification
for
Fig
.
2.0
A
25
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