Westinghouse RC, Инструкция по эксплуатации

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T Y P E RC AUTOMATIC R ECLOSI N G R E L AY
Lockout
When the drum reaches the lockout position, the
motor is de-energized, since cam contact #1 opens
(assuming the breaker is open). The breaker must
then be closed by the control switch. If the breaker
then remains closed the drum will rotate to the "Start"
position, where the motor is de-energized by the #2
cam contact.
O p t i o n a I A rra ng e m e n ts
Alternate operating arrangements are described
below.
Reclosing Through Contact Y6
As shown in figures 6, 7 and 8 the close circuit
can be energized through contact Y6, where an in­
dependent contact is required or where a reclosing
delay is desired. Y6 closes approximately 6 cycles
after 79X is energized.
Lockout Alarm
A #4 cam screw can be set to close the #4 con­
tact in the lockout position. By jumpering terminals
4 and 6 and connecting terminal 7 to an alarm cir­
cuit, an alarm will b e sounded when the breaker
locks out.
Additional Instantaneous Tripping
Contact #4 can be set to reestablish the instan­
taneous trip circuit after the last reclosure and prior
to lockout, if th e instantaneous trip pickup is about
equal to the time-overcurrent unit pickup. In this case
reestablishment of the instantaneous trip insures
breaker lockout if the fault current is near pickup
value. The instantaneous trip circuit can alternate-ly
be reestablished each time the Y unit is reset by
short circuiting the #14 contact with a jumper.
Selective One-Shot Instantaneous Reclosing
By eliminating the #3 cam in the start position
and by using terminals 16 and 17 with an external
device, selective, instantaneous reclosing can be
o btained. When the contact of the external device
closes , reclosing will occur in the same manner as
if #3 contact closed. Further reclosing by this means
can be prevented by using either the Y 1 3 and 14
contact circuit or by using the #4 contact circuit.
In the latter case, the #4 cam is set for contact clo­
sure in the start position.
Relays with Z Unit
As shown in fi gure 8 the Z unit is energized by
a 52b contact. Z unit contacts perform the same
functions as 52a and 52b contacts. The use of this
unit reduces the number of control wires required.
Motor Operation from DC
An external inverter is available for operation of
the motor from either 125 or 250 volts de . Th e DC
terminals of the inv erter are connected in place of
terminals 8 and 9 in figure 7. Terminals 8 and 9 are
then conne cted to the AC terminals of the inverter.
This arrangement permits the use of an intermittently
rated inverter, since the DC terminals are not continu­
ously energized.
C H A R A C T E R I S T I C S
The standard rating for the relay is:
Motor . . . . . . . .
X and Y Units . . . .
Z Unit (when used) .
Drum Speeds . . . . .
. 1 20/240
V. ,
60 cycles
. 1 20/240
V. ,
60 cycles
or 48/ 125
V.
D. C .
. 1 25
V .
D. C .
. 6D-90- 180-360
Sec. /Rev.
Where the motor is to be operated at 240 volts a
resistor in the bottom right side is connected in
series with the motor coil . R elays are available for
operation on 50 cycles. X
&
Y units can be supplied
for a minimum rating of 24 volts de, or with a 250
volt rating.
B u rden D a ta
The maximum burdens for the various units of the
standard RC relay when energized from a 1 20
V.
60
cycle supply are listed below :
Contactor Unit (Device 79X)
Open position . . . . . .
49 v. a.
Closed position . . . . . 33 v. a.
Solenoid Unit (Device 79Y )
Open position . . . . . . . . . .
1 5 1 v . a .
Closed position . . . . . . . . . . 84
v.
a.
Synch, Motor (Device 79M) 8.5 v. a.
Auxiliary Unit (Device 79Z)
When used
Closed position . . . . 1 0 . 5 v. a. at 120
V
60 Cycle
3 . 5 watts at
125
V.
D. C .
The burdens o f the X and Y units occur only
mome ntarily during the reclosing cycle but the motor
is energized throughout the reclosing cycle . The X
*
and Y units can be energized for a 1 minute period
and the motor for a 1 5 minute period without injury.
The Z unit can be energized c ontinuously.
9
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