22
Figure 11: Operator sequential operation diagram
Closed
voltage applied.
Undervoltage device
27 picks up.
Spring-charge motor
(88.0) energized.
L3 opens in series
with anti-pump
relay (52Y).
LS21 and LS22
operate to
de-energize spring-
charging motor.
LS41 closes to
signal closing spring
is charged.
LS9 closes close
circuit only when
closing spring is
fully charged.
Closing spring is
fully charged.
No action! Open
52b in series with
close coil (52SRC)
blocks closing
spring-release.
Close coil is
actuated through
the closed 52b
contacts and the
two normally closed
contacts of the anti-
pump relay (52Y).
breaker
is closed.
Circuit
breaker
is open.
No action! Anti-
pump relay (52Y)
picks up through
the closed LS3
contact and opens.
Closing
spring is
not charged.
The closing spring is
unlatched.
The opening spring
is charged.
Circuit breaker
auxiliary contacts
52a and 52b change
state.
The circuit breaker
closes.
LS21 and LS22 close
to energize motor
(88). LS3 closes and
LS9 opens to cancel
closing spring
signal.
52a contacts in
series with the trip
coil (52T) close to
enable a trip
operation.
Continuous
closing command.
Close coil (52SRC)
unlatches the closing
spring and the circuit
breaker closes.
Motor cutoff switches
LS21, LS22 and LS3 are
closed because the
closing spring is
discharged.
Before the spring-
charge motor has
recharged the closing
spring and opened LS3,
anti-pump relay (52Y)
picks up and seals in.
The anti-pump relay
(52Y) opens two
contacts in series with
the close coil (52SRC).
The close coil (52SRC)
is now blocked and
cannot be activated
until springs are fully-
charged and close
command is removed.
Rapid auto-reclosing. The closing spring is automatically recharged as described above.
Therefore, when the circuit breaker is closed both of its springs are charged. The closing
spring charges the opening spring during closing. As a result, the circuit breaker is capable of
an O-0.3s-CO-3 min-CO operating cycle. The dashed line shows the operating sequence
initiated by the closing command.
Closing
Tripping
Anti-pumping feature (52Y) assures a continuously applied closing command does not cause
the circuit breaker to reclose automatically after it has tripped out on a fault.
Trip
command.
Trip coil (52T) can
only be activated
when in series
connected 52a
contact is closed.
Undervoltage device (27) is
activated by opening a NC
contact in series with 27 or by
loss or reduction of tripping
voltage.
1
Secondary shunt-
release (dual-trip)
function activated
by remote trip
command contact
NO.
1
Undervoltage device (27) is
activated by closing NO contact,
shorting the 27 coil. The NO
contact is only effective with the
circuit breaker closed. Resistor
required.
1
Undervoltage device
27 unlatches the
opening spring.
1
Circuit breaker trips.
Secondary release
unlatches the
opening spring.
1
Trip coil (52T)
unlatches the
opening spring.
Footnote:
1.
Optional items.
To Next Page
Loading...
