Western Electric 407A-4, Инструкция по эксплуатации

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the operate coil of Sl2F are deenergized and S9F is released.
Thro ugh 60F, relays Sl3F and Sl4F are energized. Sl4F extin­
guishes lamps E27F "Circuit Breaker Open" and completes the
circuit of S50F to the positive of the 24-volt relay circuit.
Sl3F, a delay relay, operates after 2 seconds to energize
S61P and S67P, the contacts of which short-circuit the charg­
ing resistances in series with filter condensers FC50P and
FC51P. E26F 11Circuit B reaker Closed" is energized through
60F, as is the timing motor in Sl2F. If the breaker remains
in the closed position for a period equal to the preset ad­
justment of the timing motor, the release coil in Sl2F will
be energized and restore Sl2F to normal. If for any reason
the c ircuit breaker is tripped by the overload circuit the
above closing sequence is again started by the auxiliary
contact of the breaker between 58F and 59F. If, however,
the breaker is tripped out before the timing motor resets
Sl2F, the breaker will remain open until the manual push
button K2F "Circuit Breaker Reclose11 is operated to energize
S8F.
Plate-Circuit Breaker
Switches D55P, D56P, D57P and circuit breaker CB73P
have been provided in the distribution cabinet to permit
removing the motor-operated plate circuit breaker CB65P
from circuit for maintenance or test and to provide an
emergency method of operation in case of trouble with the
breaker. For normal operation D55P and D57P are in the
upper position and D56P is closed. CB73P must be kept in
the "OFF" In an emergency when it is necessary
to operate without the motor-operated breaker in circuit,
first make certain that CB73P is "OFF" then open D56P and
throw D55P and D57P to the lower position. "H. V. Recti­
fier" switch D4F should be kept in the "ON" position.
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