Westinghouse RC, Инструкция по эксплуатации

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TYP E RC AUTOMATIC RECLOSING RELAY
O P E R A T I O N
Operation of the relay and associated equipment
will be described, using the external schematic in
figure 7, in conjunction with figures 4 and 5, which
show contact positions as a function of the drum posi­
tion. Fi gure 5 is based on the factory cam adjust­
ment- immediate, 1 5 and 45 second reclosures, with
one drum revolution in 60 seconds . It is further as­
sumed in figure 5 that the instantaneous trip is locked
out after the first reclosure , and the fault is not
cleared prior to lockout.
M otor Contro l
Motor energization is controlled b y cams 1 and 2.
In the start position the motor is energized through
1f1 and 52b contacts when the breaker opens. As the
drum moves away from the start position, 1f2 contact
closes to energize the motor through the 52a contact
during the time that the breaker is closed. If the
breaker is closed at the lockout position the drum
will continue to rotate until the 1f2 contact opens at
the start position.
If
the breaker is open, the drum
will stop in the lockout position, since the 1f1 , 52a
and Y7 contacts are all open at this point.
Contact Y7 keeps the motor energized when the
breaker remains closed after an immediate reclosure
until the #2 contact can close. For this condition,
52b opens before the drum can rotate sufficiently to
close the #2 contact. Contact Y7 has no significance
during subsequent reclosing operations.
C l o s i n g S e q ue n c i n g
The number o f reclosures_ and the time at which
they occur is determined by the location of the #3 cam
screws , which close the #3 contact.
I n s ta n ta neo u s T r i p L o ck o u t
As shown in fi gures 5 and 7, the trip circuit of
the instantaneous tripsunits is opened by Y 1 3 and
14 contacts from the time of the first reclosure until
the drum returns to the start position. During the
initial reclosing, contact Y 1 3 is opened and remains
open until the Y unit is completely reset at 6 seconds.
Th e purpose of contact Y 1 3 is to keep the trip cir­
cuit open until cam contact, 14, can be opened by the
drum rotation. Contact Y 1 3 has no significance during
subsequent reclosing operations.
X - Y C i rc u i t
Referring to figure 7 , when the breaker close cir­
c uit is energized through 5 2bb, Y5 and #3 contacts ,
the 7 9X coil is also e nergized. Then, X8 and X9
contacts seal around the Y5 contact and energize
4
79Y coil, respectively. Contact Y5 opens and re­
mains open until the Y unit is completely reset at 6
seconds. As the breaker close s , 52bb contact opens,
d e-energizing the X and Y coils. Should the breaker
immediately trip again, contacts Y5 and
X8 will be
open to prevent premature energization of the breaker
close circuit.
C o m p l e te O p era t i n g S e q ue n c e
Fault-Trip - Immediate Reclosure
Refer to figure 7. With the timing drum in the
"Start" position, a #3 cam spring will be holding
contact #3 closed. The breaker switch contacts 52b
and 52bb close, energizing the motor 79M through
contact # 1 , and th e drum begins to rotate. At the
same time the coil of the contactor unit, 79X, is en­
ergized through drum contact #3 , contact Y5 , and
inte grating lockout contact 9A, when used. When
th e breaker latch checking switch, 52LC, closes, the
breaker control relay 52X is immediately energized
through the preclosed contacts Y5 and 3 . This in
turn energizes the closing coil of the breaker, 52C.
Simultaneously , contactor unit, 7 9X, seals in through
its contact X8, while its other contact, X9, energizes
the coil of solenoid unit 79Y to open contacts Y5 and
Y 1 3 and close contacts Y6 and Y7. As the circuit
breaker closes, th e breaker auxiliary switches 52b
and 52bb open, and 52a closes . Opening 52bb de�
e nergizes 79X and 79Y . The latter then resets against
its latch to open contact Y6 and remains in this posi­
tion, thus leaving contacts Y5 and Y 1 3 open and
contact Y7 closed until the latch is released. Before
the latch is released, the drum-operated contact, 1 4 ,
will b e opened and will remain open until the drum
returns to the "Start " position.
Preparing for Second Reclosure
The drum continues to rotate , since the motor is
energized through Y7. When the breaker trips the
second time , no immediate operation occurs. At about
one second , 1f2 cam contact closes to set up the motor
circuit when the breaker is subsequently reclosed. At
about the three second drum position contact
1t3
opens.
At about
6
seconds, the Y unit latch is released by
the 1f5 cam, resetting the Y unit. The relay is now
ready for another reclosure as soon as contact 1f3 is
closed by the 1f3 cam spring. The drum will continue
to rotate , since the motor is energized through 52b
and 1t 1 contacts.
Second and Third Reclosures
At 15 and 45 seconds the #3 contact closes to
reclose the breaker. After each reclose , the Y unit
is unlatched by the action of cam #5 .
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