Rapid Auto-Reclosing; Manual Operation; Manually Charging The Closing Spring (Figure 6); Manual Closing (Figure 6) - Siemens 3AH Instructions, Installation, Operation, Maintenance

Interrupter/Operator Description
Elementary Diagram
Figure 8. Typical Elementary Diagram

Rapid Auto-Reclosing

Since the closing spring is automatically recharged by the
motor operating mechanism when the breaker has closed
the operating mechanism is capable of an open-close-open
duty cycle as required for rapid auto-reclosing.

Manual Operation

Electrically operated vacuum circuit breakers can be oper-
ated manually if the control supply should fail.

Manually Charging the Closing Spring (Figure 6).

Insert the hand crank (50) in hole (50.1) and turn it clock-
wise (about 45 revolutions) until the indicator (55) shows
"Charged". The hand crank is coupled with the charging
mechanism via an over-running coupling; thus the opera-
tor is not exposed to any risk should the control supply
recover during charging.

Manual Closing (Figure 6)

Press the close button (53). The close-open indicator (58)
will then display "Closed" and the closing spring condi-
tion indicator will now read "Discharged".

Manual Opening (Figure 6)

The tripping spring is charged during closing. To open the
breaker, press the trip button (54) and "Open" will be dis-
played by indicator (58).

Indirect Releases (Dual Trip or Undervoltage)

The indirect release provides for the conversion of mod-
est control signals into powerful mechanical energy im-
pulses. It is primarily used to trip medium voltage circuit
breakers while functioning as a secondary (dual trip) re-
lease or undervoltage release device.
These releases are mechanical energy storage devices.
Their internal springs are charged as a consequence of
the breaker mechanism operation, This energy is released
upon application or removal (as appropriate) of applicable
control voltages. Refer to Figures 9, 10 and 11.

Secondary (Shunt) Release

A secondary shunt releases (extra trip coil) is used for elec-
trical 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 sup-
ply used for the normal trip coil.
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