Voltage and frequency protection

Voltage and Frequency protection – Reyrolle 7SR158

Reyrolle 7SR158

The Reyrolle 7SR158 Argus voltage and frequency relays are numerical, multifunctional devices, with functionality designed for connection to voltage transformers.

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Features & functions

Voltage and frequency protection Reyrolle 7SR158


The voltage and frequency functionality is supplemented by data storage, instrumentation, user configurable logic and data communication features. A menu based user-friendly interface provides local access to relay settings, instruments and operational data. The fascia also benefits from 9 user configurable, tri-coloured LEDs and a USB port for PC access.

The key functions provided include 27/59 -under and overvoltage, 81 -under and over frequency, 78 -Voltage vector shift and 81R -Rate of change of frequency.

Relays have three voltage inputs, six binary inputs and eight binary outputs and are housed in a size E4 case. Programmable logic is provided to allow the optimal configuration of relay functionality. A rear electrical RS485 port is provided for SCADA connection using either IEC60870-5-103, DNP3.0 or MODBUS RTU protocol.


Protection functions

  • Under/over voltage

  • Under/over frequency

  • Rate of change of frequency

  • Negative phase sequence voltage

  • Neutral voltage displacement

  • Voltage vector shift

Supervision functions

  • Trip and close circuit supervision

  • Lockout

Monitoring functions

  • Primary/secondary line and phase voltages

  • Historical demand record

  • Positive phase sequence (PPS) voltage

  • Negative phase sequence (NPS) voltage

  • Zero phase sequence (ZPS) voltage

Further functions

  • Four settings groups

  • 2 levels password protection

  • Self monitoring

  • Circuit breaker trip and maintenance counters

  • Fault, event and waveform records

  • Programmable user logic

  • User alarms

  • Virtual inputs/outputs

  • Front USB communication port

  • Rear RS485 communication port