Siemens GMSG

Vacuum interrupter/operator
Figure 19: Construction of secondary shunt release
23.0
1.0 - Magnet core
3.0 - Housing
5.0 - Mounting holes
7.0 - Magnet coil
9.0 - Magnet armature
11.0 - Tension spring
13.0 - Adjusting (factory-set) screw
for 11.0
These releases are mechanical-energy
storage devices. Their internal springs are
charged as a consequence of the circuit
breaker mechanism operation. This energy
is released upon application or removal (as
appropriate) of applicable control voltages
(refer to Figure 19: Construction of
secondary shunt release and Figure 20:
Latch details on page 26 and Figure 21:
Undervoltage lock/operate selection on
page 27).
Secondary shunt release (optional)
(54.2)
A secondary shunt release (second trip
coil) is used for electrical tripping of the
circuit breaker by protective relays or
manual-control devices when more than
one trip coil is required. The second trip
coil is generally connected to a separate
auxiliary supply (dc or ac) from the control
supply used for the normal trip coil.
Undervoltage release (optional) (54.2)
The undervoltage release is used for
continuous monitoring of the tripping-
supply voltage. If this supply voltage falls
excessively, the undervoltage release will
provide for automatic tripping of the circuit
breaker.
The undervoltage device may be used for
manual or relay tripping by employing a
contact in series with an undervoltage-
device holding-coil.
Relay tripping may also be achieved by
employing a normally open contact in
parallel with the holding coil. If this
scheme is used, a resistor must be
provided to limit current when the
normally open contact is closed.
Secondary and undervoltage releases are
available for all standard ANSI/IEEE control
voltages.
Figure 20: Latch details
15.0 - Tripping pin
21.0 - Locking pin
23.0 - Striker pin
25.0 - Latch
27.0 - Spring
31.0 - Striker-pin spring
33.0 - Terminal block
13.0
9.0
15.0
5.0
3.0
11.0
21.0 25.0 27.0
7.0
31.0
33.0
1.0
21.0 - Locking pin
23.0 - Striker pin
25.0 - Latch
27.0 - Spring
29.0 - Lower connection terminal
23.0 25.0
29.0
21.0
27.0
Locked/unlocked selection screw
(undervoltage release only)
Shown charged
Shown charged
26