Richards 137NP, Инструкция по эксплуатации, Страница: 19 / 53

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A. Phasing
Phase out connections to protector to insure that “cross-phase” connection will not be made
when the breaker is closed. Network voltage is available on network side of fuse mounting.
Transformer voltage is available on opposite end of fuse mounting when the protector is
closed.
B. Manual Operation
Close and open the breaker several times by hand. To do this swing the manual operating
handle from the “open” to the “closed” position and when the breaker is closed return to the
“open” position. The breaker should close with considerable pressure. If the hand-wheel of
the motor is turned the motor cam may be advanced to a position where it will prevent the
normal resetting of the mechanism after tripping. If this happens, turn the hand-wheel
clockwise until the mechanism resets. Then turn two more revolutions. Now close the
breaker manually and trip by lifting the extended lever above the trip coil. Repeat this
operation, returning the manual handle to the “automatic” position. The trip mechanism and
operating mechanism should reset.
C. Electro-mechanical Relays
The correct operation of the electromechanical type network master relay depends upon the
application to the relay coils of currents and voltages of the proper phase sequence. For this
reason the phase sequence of the network should be checked before putting a protector into
service. This can be done by making a temporary reconnection of the phasing relay and
observing its operation as follows:
1. Make the temporary change in the wiring of the phasing relay as indicated on the
wiring diagram for the network protector.
2. Replace test caps B, C, and F only.
3. Trip protector open and move operating handle to “open” position. Do not close
protector during this test.
4. Connect the network side of the protector to the network.
5. Observe the operation of the phasing relay contacts. If the relay contacts close with a
strong torque toward the right, the phase sequence is 1, 2, 3. If the relay contacts
open or move to the left, the phase sequence is 3, 2, 1.
The phase sequence of the protector is determined by the lead connections as shown on
the wiring diagram. In general, network protectors are wired for 1, 2, 3 phase sequence at
the factory. Protectors may be obtained which are wired 3, 2, 1 phase sequence if
desired. (Note: Protectors wired for 1, 2, 3 phase sequence may be used with a 3, 2, 1