Rishabh Instruments Limited
Rish Relay 256-PHV - Combined Under/Over Voltage & Frequency Relay

Rish Relay 256-PHV - Combined Under/Over Voltage & Frequency Relay

The combined voltage & frequency protectors give continuous surveillance of the monitored circuit. The product offers user-adjustable trip points (set points) for voltage and frequency, plus an adjustable time delay setting.

  • Adjustable setpoint
  • Adjustable Time Delay
  • Internal differential ( factory Settable )
  • LED trip indication
  • 2 pole relay contacts
  • Energize/De-energize function swapping
  • Auto Reset

Product Function

1. Over Voltage & Frequency: When the monitored value exceeds the setpoint and the time delay has elapsed, the relay will energize and the red LED will illuminate to indicate the trip condition.

2. Under Voltage & Frequency: The relay will de-energize after the time delay has elapsed, and the red LED will extinguish to indicate the trip condition.

Applications

Since speed is proportional to the frequency, this protector can be used to protect for :

Over frequency

Under frequency

Over speed

Under speed

Under voltage

Over voltage

Gensets - to monitor the correct operation of the AVR (Automatic Voltage Regulator) & excitation system & engine speed controller (Governor)

Motors - Some electric motors are voltage-sensitive and can overheat & burn out when operated at low voltages. Synchronous motors rotate at a speed proportional to line frequency. Use these relays to ensure the correct running speed.

UPS supplies - when the main A.C. supply falls outside the acceptable operating voltage window, the relays can initiate a changeover to an alternate or standby supply.

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