Siemens GMI Series

Interrupter
/
Operator
Description
Limit
Switches
(
Figure
27
)
-
The
motor
cutoff
switch
(
LS
1
)
is
used
to
sense
the
position
of
the driven
mechanisms
.
This
switch de
-
energizes
the
charging
motor
when
the
Charged
position
of
the
closing
springs
is
reached
.
When
the
closing
springs
are
discharged
,
this
switch
energizes
the
control
circuit
powering
the
spring charging
motor
.
Spring
charged
switch
(
LS
2
)
operates
simultaneously
with
motor
switch
(
LS
1
)
.
The
spring charged
switch allows
the
close
solenoid
to
be
energized
only
when
the
springs
are
charged
,
and
also
is
part
of
the anti
-
pump
circuitry
.
The
trip
latch
check switch
(
LS
3
)
operates
when
the
trip
latch
linkage
is
in
the
reset
position
.
It
also is driven
by
operating
bars
that
sense
when the breaker is
in
either the Test
or
Connected
position
inside the
switchgear
.
Control
circuitry
prevents
an
electrical
release
of
the
closing springs
unless the breaker is either
in
the Test
or
Connected
position
,
or
is
out
of
the
compartment
.
The
spring
dump
switch
(
LS
4
)
operates
when the
circuit breaker
is removed
from
,
or
is
being
inserted into
,
the
cubicle
.
Automatic
spring
charging
by
charging
motor
occurs
when
secondary
control
power
is available
,
and
motor
cutoff
switch
LS
1
has
not
operated
.
The
springs
are
automatically
re
-
charged
after
each
closing
operation
.
Electrical
closing
occurs
with
closing
control
power
applied
and when
all
of
the
following
conditions exist
:
1
)
External
control
switch
CS
/
C
is closed
;
2
)
Anti
-
pump
relay
52
Y
is
not
energized
;
3
)
Auxiliary
switch
52
b indicates the breaker
is
in
open
position
;
4
)
Limit
switch
LS
3
shows that
the
trip
latch has
been
reset
and the circuit
breaker is
in
the
Test
or
Connected
position
,
or
is
out
of
the
compartment
;
and
5
)
Limit
switch
LS
2
indicates
that the
closing
springs
are
charged
.
Electrical
tripping
occurs
with
tripping
control
power
applied
and
when
the
auxiliary
switch
52
a
shows
the
breaker
is closed
,
and
a
trip
signal
is
provided
by
the control
switch
CS
/
T
or
the
protective
relays
.
While external
control
power
is
required
for
either
electrical
closing
or
tripping
,
the circuit breaker
can
be
manu
-
ally
charged
,
closed and
tripped
without
external
control
power
.
Capacitor
Trip
Device
(
Optional
)
The
capacitor
trip
device is
an
auxiliary
tripping
option
provid
-
ing
a
short
term
means
of
storing
adequate
electrical
energy
to
ensure
breaker
tripping
.
This
device is
applied
in
breaker
installations
lacking
indepen
-
dent
auxiliary
control
power
or
station
battery
.
In
such
instal
-
lations
,
control
power
is
usually
derived
from
the
primary
source
.
In
the
event
of
a
primary
source
fault
,
or
disturbance
with
attendant
depression
of
the
primary
source
voltage
,
the
capacitor trip
device
will
provide
short
term
tripping
energy
for
breaker
opening
due
to
relay
operation
.
Standard
Schematic
Diagrams
Note
:
Figure
28
a
shows
a
typical
schematic
for
a
circuit
breaker which
is
not
specifically
intended
for
reclosing
appli
-
cation
,
while
Figure
28
b
shows
a
breaker
for
reclosing
service
.
Figure
28
c
shows
a
breaker
with
capacitor
tripping
.
These
are
typical
—
refer
to
the
specific
drawing
for
your
project
.
Inspection
of
the schematic
diagrams
shown
in
Figures
28
a
-
28
c
provides
a
clear
picture
of
the
logic
states
of
the various
devices
for
the three basic control
functions
.
These
are
:
1
)
automatic
charging
of
the
closing
springs
;
2
)
electrical
closing
of
the
primary
contacts
and
3
)
electrical
tripping
of
the
primary
contacts
.
21697
-
93
21696
-
93
Figure
27
:
Circuit
Breaker
Limit
Switches
.
17
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