Quantcast Manual Closing

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Custom Search Automatic Reclosing. When a circuit breaker is provided with automatic reclosing
equipment, the automatic reclosing shall be cut off (rendered inoperative) before the breaker is
tripped or closed. The recloser relay can be cut off by moving the recloser cutoff switch to the
off position. The automatic reclosing shall be left inoperative until the circuit breaker is again
closed and has remained closed for a few seconds. The automatic reclosing can be turned on by
moving the recloser cutoff switch to the on position. If a circuit breaker has opened
automatically, and the automatic reclosing has operated to lock out or has failed to operate, the
automatic reclosing shall be cut off before the circuit breaker is closed manually or electrically. Manual Closing. Manually operated circuit breakers are closed by hand with a
handle that is connected directly to the circuit breaker or is remotely connected to the circuit
breaker through a system of levers, a bell crank, and rods. Successful operation of such breakers
is dependent upon the operator applying positive unhesitating force through the entire travel of
the operating handle. Even under normal load-switching conditions, slow or hesitant closing
may result in excessive burning of the contacts, which may ultimately impair the breaker's ability
to function properly. Some stored-energy closing mechanisms, such as a charged spring or
hydraulic type, can be closed manually in case of control power failure. The spring or the
hydraulic system can be charged manually to close the breaker. Electrical Operation. The basic functional requirements of the controls of all
modern circuit breakers are as follows:
(a) The circuit breaker mechanism will complete its closing operation, including
automatic cutoff of the closing power, after a closing operation has been initiated, even though
the operator releases the control switch before the circuit breaker is completely closed.
(b) Only one closing operation of the circuit breaker mechanism will result from each
actuation of a manual control device (push button, switch), even though the circuit breaker trips
while the control switch is being held in the closed position.
(c) If the control power supply is removed during an uncompleted closing operation, all
control devices will be restored to the normal circuit breaker upon position. An additional
operation of the control switch will be required to close the circuit breaker.
(d) When a circuit breaker is in the closed position, initiation of a closing operation
will not result in an operation of the closing mechanism.
(e) When a closing operation of a circuit breaker (having a stored-energy-type
operating mechanism; such as air, oil, or charged spring), cannot be completed successfully
because of the absence of an adequate supply of stored energy, all actuating devices in the control
circuit remain in the normal circuit breaker open position (when the initiating control device is
operated and the breaker will not operate).


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