GE AK-50 - Circuit Breaker Maintenance and Safety; Electrical Tripping Function; Inserting the Safety Pin

GEI
-
74600
Low
-
voltage
Power
Circuit
Breakers
Mechanism
.
It
shows
the
control
cir
-
\
cult
when the
closing
springs
are
dis
-
•
charged
and
the
breaker
open
.
When
rated
voltage
is
applied
to
the
control
circuit
,
the
motor
R
(
l
-
2
)
is
en
-
ergized
through closing
relay
contacts
K
(
8
-
4
)
(
3
-
7
)
and
cutoff
switch
contacts
G
(
2
-
l
)
(
3
-
4
)
.
As
the
motor
charges
the
closing
springs
,
the
F
and
G
cutoff
switches
are
mechanically
operated
,
opening
the
G
contacts
and
closing
the
F
contacts
.
When
contacts
G
(
1
-
2
)
(
3
-
4
)
open
,
the
motor
is de
-
energized
,
with
the
closing
springs
now
in
the
’
tharged
"
position
and
ready
for
a
closing signal
.
The
indicator
on
the
front
escutcheon
will indicate the
charged
position
.
A
closing signal
now
given energizes
the
closing
relay
K
(
5
-
6
)
,
whose
con
-
tacts
K
(
8
-
2
)
(
1
-
7
)
close
,
with the
relay
being
sealed
in
by
contacts
K
(
8
-
2
)
and
F
(
4
-
3
)
.
With
the
closing
relay
ener
-
gized
and the
F
cutoff
switch
contacts
closed
,
the
motor
R
(
l
-
2
)
is
again
ener
-
gized
through
contacts
K
(
8
-
2
)
,
F
(
2
-
l
)
,
and
K
(
l
-
7
)
,
further
charging
the
clos
-
ing springs
and
causing
the
output
crank
of
the
gear
reduction
unit
to
go
over
a
top
dead
-
center
position
.
Be
-
yond
this
position
the
springs
discharge
independently
of
the
charging
motor
sand the
breaker closes
.
6
1
.
Auxiliary
Switch
Z
.
Channel
-
shaped
Bar
3
.
Position
Indicator
4
.
Relay
5
.
Manual
Trip
Button
6
.
Closing
Button
7
.
Shaft
for
Manual
Mainte
-
nance
Closing
Handle
8
.
Spring
Charged
-
Discharged
Indicator
9
.
Motor
Cut
-
off
Switches
10
.
Arc
Quencher
Froni
view
of
AK
-
J
-
50
breaker
Fig
.
2
.
ELECTRICAL
TRIPPING
rotating
the
trip
shaft and
displacing
the
trip
latch
.
When
the breaker closes
,
the
cutoff
switches
revert to
their
original
po
-
sition
and
on
release
of
the
closing
switch
,
relay
x
is
de
-
energized
and
the
motor
recharges
the
springs
to
the
pre
-
charged
position
.
On
some
models
,
an
auxiliary
switch
,
fb
"
contact
is
placed
in
the
motor
circuit
to
prevent
pre
-
charging
when the
breaker is
in
the
closed
position
.
The
breaker
may
be
tripped
elec
-
trically
by
any
of
the
electrical
trip
-
ping
devices described
in
these
in
-
structions
.
The breaker
may
also be
tripped
by
the automatic
over
cur
rent
or
reverse
current
tripping
devices
,
if
so
equipped
.
All
these devices
trip
the
breaker
in
a
similar
manner
,
i
.
e
.
the
device
trip
arm
moves
against
the
trip
paddles
fastened
on
the
trip
shaft
,
thus
The
most
commonly
used
tripping
device
is
the
shunt
trip
device
con
-
nected
in
the control
circuit
as
shown
in
Fig
.
1
.
When
a
tripping signal
is
given
,
the shunt
trip
coil
M
(
i
-
2
)
is
energized through
a
normally
-
open
auxiliary
switch
"
a
"
contact
L
(
l
-
lc
)
,
thus
tripping
the breaker
.
MAINTENANCE
BEFORE
INSPECTION
OR
ANY
MAINTENANCE
WORK IS DONE
,
BE
SURE
THAT
THE
BREAKER
IS
IN
THE
OPEN POSITION
.
ALL
ELEC
-
TRICAL
POWER
,
BOTH
PRIMARY
AND
CONTROL
SOURCES
,
SHOULD
ALSO
BE
DISCONNECTED
.
is
in
the
open
position
and
the
closing
springs
are
being
re
-
strained
by
the
safety
pin
.
The
procedure
for
inserting
the
safety
pin
is
given
below
.
INSERTING SAFETY
PIN
AK
-
50
,
-
75
and
-
100
(
Fi
9
.
3
)
The
closing spring
should
be
charged
with the
maintenance
handle
(
1
)
so
that
the
safety
pin
(
3
)
can
be
placed
in
the hole
of
the
push
rod
(
2
)
.
Con
-
tinue
to
operate
the maintenance
han
-
so
that
the
safety
pin
takes
the
spring
force
*
To
install
the
safety
pin
of
the
AK
-
2
manual stored
-
energy
mecha
-
nism
refer
to
the section
entitled
AK
-
2
STORED
-
ENERGY
MANUAL
MECHA
-
NISM
on
page
14
of
these
instructions
.
Warning
;
On
breakers
em
-
ploying
stored
-
energy
closing
mechanisms
,
care
must
be
taken
when
the
circuit
breaker
is
being
installed
and
when
any
inspection
or
maintenance
work
With
the
safety
pin
restraining
the
closing
spring
force
,
the
contacts
will
close
slowly
when
the
breaker
is
manu
-
ally
operated
allowing
the
operation
of
the mechanism and
the
contact
align
-
i
c
hAi
'
ntr
Arma
enfkaf
tKo
alar
i
nrr
tlto
Kraalrar
c
ie
+
K A
I ti
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A KP
nn
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