Siemens 3AH3 Instruction Manual page 22

Figure 11: Operator sequential operation diagram
Closing
voltage applied.
Undervoltage device
27 picks up.
LS21 and LS22
operate to
de-energize spring-
charging motor.
No action! Open
52b in series with
close coil (52SRC)
blocks closing
spring-release.
52a contacts in
series with the trip
coil (52T) close to
enable a trip
operation.
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.
Tripping
Trip coil (52T) can
only be activated
when in series
connected 52a
contact is closed.
Trip coil (52T)
unlatches the
opening spring.
22
Closed
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.
Spring-charge motor
(88.0) energized.
Closing spring is
fully charged.
L3 opens in series LS41 closes to
with anti-pump signal closing spring
relay (52Y).
is charged.
Circuit Circuit
breaker
breaker
Close coil is
is closed.
is open.
actuated through
Closing
the closed 52b
command
contacts and the
when
two normally closed
contacts of the anti-
Closing
pump relay (52Y).
spring is
not charged.
No action! Anti-
pump relay (52Y)
The closing spring is
picks up through
unlatched.
the closed LS3
contact and opens.
Circuit breaker
auxiliary contacts The circuit breaker
52a and 52b change closes.
state.
Undervoltage device (27) is
activated by opening a NC
contact in series with 27 or by
loss or reduction of tripping
voltage.
1
Undervoltage device
27 unlatches the
opening spring.
Circuit breaker trips.
LS9 closes close
circuit only when
closing spring is
fully charged.
The opening spring
is charged.
LS21 and LS22 close
to energize motor
(88). LS3 closes and
LS9 opens to cancel
closing spring
signal.
Trip
command.
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
1
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.
Footnote:
Optional items.
1.
Secondary shunt-
release (dual-trip)
function activated
by remote trip
command contact
NO.
1
Secondary release
unlatches the
opening spring.
1