ABB VHK-R - AC Operating Sequence

II
IK
IK
MIPIP
ID
U
.
^
.
/
.
/
V
/
Page
11
ASEA
BROWN
BOVERI
AC
CLOSING
OPERATING
SEQUENCE
10
.
The
latch
check
switch
,
if
furnished
,
insures
that
the
operating
mechanism
must
be
reset
prior
to
energizing
the
closing
latch
release
coil
(
X
)
.
With
the
circuit
breaker
open
,
the
closing
springs
uncharged
,
and
the
control
power
source
energized
across
disconnects
"
5
"
&
"
02
"
and
"
01
"
&
"
6
"
,
motor
disconnect
switch
closed
,
operation
occurs
as
follows
:
11
.
The
remote
mounted
capacitor
trip
feature
,
if
furnished
,
provides
an
electrical
energy
storage
network
,
whereby
should
a
loss
of
control
power
occur
at
the
instant
of
a
tripping
signal
,
sufficient
energy
will
be
furnished
to
insure
an
electrical
tripping
operation
.
1
.
Im
mediately
upon
the
availability
of
control
power
at
secondary
disconnects
"
5
"
and
"
02
"
,
the
spring
charging
motor
(
motor
)
is
energized
,
which
in
turn
charges
the
closing
springs
.
When
the
closing
springs
are
charged
,
limit
switch
contact
"
LSa
"
is
closed
.
Also
,
upon
availability
of
control
power
at
secondary
disconnects
"
01
"
and
"
6
"
and
after
the
closing
springs
have
been
charged
,
the
lockout
relay
coil
(
Y
)
will
be
energized
through
the
circuit
breaker
auxiliary
switch
"
b
"
contact
and
the
parallel
resistors
Ri
and
R
2
.
The
lockout
relay
will
pick
up
and
close
contact
"
Ya
"
.
12
.
The
stopping
device
switch
,
if
applicable
,
prevents
electricai
reclosing
of
the
Circuit
Breaker
after
a
manual
trip
until
the
stopping
device
switch
has
been
manually
reset
.
2
.
Connecting
secondary
disconnects
"
03
or
"
7
"
to
control
via
operation
of
the
close
control
switch
energizes
the
latch
release
coil
(
X
)
through
the
circuit
breaker
auxiliary
switch
"
b
"
contact
,
the
normally
open
lockout
relay
contact
"
Ya
"
,
and
the
limit
switch
contact
"
LSa
"
.
The
latch
release
coil
(
X
)
releases
the
closing
latch
.
The
springs
then
discharge
to
close
the
circuit
breaker
.
3
.
When
the
springs
discharge
,
limit
switch
contact
"
LSb
"
closes
and
limit
switch
contact
"
LSa
"
opens
.
4
.
When
limit
switch
contact
"
LSb
"
in
the
motor
circuit
closes
,
the
spring
charging
motor
is
energized
,
which
in
turn
recharges
the
closing
springs
.
5
.
When
the
circuit
breaker
closes
,
all
auxiliary
switch
"
b
"
contacts
open
and
all
auxiliary
switch
"
a
"
contacts
close
.
6
.
When
the
limit
switch
contact
"
LSa
"
opens
,
both
the
latch
release
coil
(
X
)
and
the
lockout
relay
coil
(
Y
)
are
deenergized
.
Contact
"
Ya
"
opens
the
latch
release
coil
(
X
)
circuit
.
Contact
"
Yb
"
closes
connecting
resistors
"
R
1
"
and
"
R
2
"
directly
to
control
power
as
long
as
the
close
control
switch
remains
closed
.
The
circuit
breaker
is
prevented
from
any
automatic
reclosing
in
the
event
"
LSa
"
and
auxiliary
switch
"
b
"
close
because
"
Ya
"
remains
open
.
The
"
Yb
"
contact
shorts
out
the
lockout
relay
coil
(
Y
)
through
resistors
"
R
1
"
and
"
R
2
"
.
The
purpose
of
the
lockout
relay
is
to
prevent
pumping
of
the
circuit
breaker
'
s
mechanism
when
closing
against
a
faulted
circuit
.
7
.
After
the
breaker
has
closed
and
when
the
closing
control
switch
is
released
by
the
operator
,
the
lockout
relay
coil
(
Y
)
remains
deenergized
due
to
the
auxiliary
switch
"
b
"
contact
in
the
closing
circuit
being
open
.
8
.
The
circuit
breaker
can
be
tripped
by
operation
of
the
"
Remote
Trip
"
switch
,
which
energizes
the
circuit
breaker
trip
coil
(
TC
)
through
the
auxiliary
switch
"
a
"
contact
.
9
.
The
undervoltage
device
,
if
furnished
,
provides
a
direct
acting
lock
-
open
and
undervoltage
tripping
feature
.
This
device
must
be
energized
to
initially
close
the
breaker
,
and
also
to
maintain
the
breaker
in
a
closed
position
.
Courtesy of NationalSwitchgear.com