Single Phasing Preventer

Single Phasing Preventer

Type PFV Phase Failure Relay, popularly called Single phase preventer. It operates almost instantaneously and protects the motor under any of the following conditions:

• When there is disconnection of any one of the lines to the motor.
• When the motor connections are reversed in phase.
• When supply voltage is unbalanced

Construction

The electronic circuit is of the most modern design and high grade components are used to ensure efficient performance.

• It is designed to be used for motors of any HP.
• LED is provided on the relay which will be off in case of Single Phasing or Phase reversal of input terminals of the motor
• It is normally supplied in a moulded dust proof enclosure
• Relay can be supplied with time delay and under / over voltage cut-off if required.

Tests

• When there is disconnection of any one of the lines to the motor.
• When the motor connections are reversed in phase.
• When supply voltage is unbalanced.
  

Specifications

System	415 V, 3Ph, 50Hz.
Voltage Variation	+10% and -20% of system Voltage
Auxiliary supply	1 set of 1N/o and 1N/c
Relay contacts	Change over contacts.
Rating of relay contacts	AC - 400 VA (Resistive) or 220 VA (Inductive) with Max 5 amps at 415 volts.