Phase Protection Relays

Phase Protection Relays

Product Features

  • Protects against loss of phase and incorrect phase sequence
  • Protects against phase reversal and under voltage
  • LED indication
  • DIN rail mounting
  • Single or double pole output available
  • Optional built-in time delay

Phase protection relays continuously monitor a three phase AC power supply, tripping upon fault condition. These relays protect against total loss of a phase (phase failure), incorrect phase sequence (rotation), symmetrical under voltage and asymmetrical under voltage. The A866PSI model also offers phase sequence and fault indication. The internal relay remains energised and the LED illuminates only when the power supply is satisfactory for connection to the three phase equipment. The under voltage trip point on all three phases is fixed at 85% of the nominal voltage, although an alternative trip point may be possible upon request. The relays are self powered, requiring no auxiliary power supply and are available with either a single or double pole changeover relay output and optional built-in time delay.


Datasheet

Key Terms: B866/3W - B866/4W - A866PSI/3W - A866PSI/4W - TA866 - Phase - Failure - Protection Relay