Transformer protection and control RET620 IEC

Compact protection and control with voltage regulation for two-winding power transformers

RET620 is a dedicated transformer management relay for the protection, control, measurement and supervision of both power and step-up transformers, including power generator-transformer blocks, in utility and industrial power distribution systems. RET620 is also ideal for voltage regulation.

Compact and versatile two-winding power transformer protection relay with integration of protection, control, monitoring and supervision in one relay.

RET620 is a member of ABB's Relion® family and part of its 620 protection and control product series.


  • Protection for two-winding power transformers

Key benefits

  • Extensive protection and control functionality
  • Functional scalability and extensive possibilities to easily tailor configurations to application-specific requirements
  • Withdrawable plug-in unit design for swift installation and testing
  • Large graphical display showing customizable SLDs, accessible either locally or through an easy-to-use web-browser-based HMI
  • Extensive life-cycle services

Key features

  • Extensive range of protection and control functionality for two-winding power transformers, including advanced and fast differential protection with high inrush stability
  • Supports various neutral earthing options, matching either high-impedance or numerical low-impedance restricted earth-fault principles
  • Optionally can also include automatic voltage regulation of power transformers with a motor-driven on-load tap changer and arc protection
  • Supports native IEC 61850 Edition 1 and 2, including redundancy HSR and PRP, GOOSE messaging and IEC 61850-9-2 LE for less wiring and supervised communication
  • Supports Modbus, DNP3 and IEC 60870-5-103 communication protocols and different time synchronization methods, including high-accuracy time synchronization via IEEE 1588 V2 Precision Time Protocol

Are you looking for support or purchase information?

Have you seen REX615, the next step for our 615 and 620 series relays?

Go to REX615

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