ABB REF620 Feeder Protection and Control Relay

Configured for feeder protection, control, measurement, and supervision in medium-voltage distribution systems, the ABB REF620 IEC (REF620 feeder protection and control relay) provides direct protection and control functions for incoming and outgoing feeders. It supports radial, looped, and meshed networks, including systems with distributed power generation, and communicates through IEC 61850, Modbus, DNP3, and IEC 60870-5-103 protocols.

Hardware Specifications

IEC 61850 and Feeder Protection Functions

REF620 supports native IEC 61850 Edition 1 and Edition 2 communication. HSR and PRP redundancy can be used for network availability, while GOOSE messaging provides supervised peer-to-peer communication between protection and control devices. IEC 61850-9-2 LE is supported for process-level communication and can reduce conventional wiring requirements.

The relay provides an earth-fault protection portfolio that includes multifrequency admittance-based protection. Optional functions include short-circuit and earth-fault location, interconnection protection for distributed power generation, capacitor bank protection, basic motor protection, and arc protection.

Protection and control functions can be configured for application-specific feeder requirements. The withdrawable plug-in construction separates the relay unit from the fixed installation interface during installation and testing procedures.

Frequently Asked Questions

Q: Which communication protocols are supported by REF620 IEC?
A: The supplied data specifies IEC 61850 Editions 1 and 2, Modbus, DNP3, and IEC 60870-5-103. IEC 61850 support includes HSR, PRP, GOOSE, and IEC 61850-9-2 LE.

Q: Can REF620 use conventional instrument transformers?
A: Yes. The supplied specifications state that the relay can operate with sensors or conventional instrument transformers.

Q: Does REF620 provide network time synchronization?
A: Yes. The relay supports multiple time synchronization methods, including IEEE 1588 V2 Precision Time Protocol for high-accuracy synchronization.

Field Installation Guidelines

Install the REF620 withdrawable plug-in unit in the specified protection panel assembly and verify the mechanical engagement of the unit before energization. Confirm that the fixed interface, terminal connections, and protective earth arrangement correspond to the applicable ABB installation documentation.

Route current transformer, voltage transformer, sensor, control, and communication wiring separately where required by the panel design. Maintain appropriate physical separation between power circuits and communication or low-level signal wiring.

For IEC 61850 networks, verify the configured Ethernet topology and confirm HSR or PRP connections where redundancy is specified. Check GOOSE subscriptions, communication supervision, and device addressing before placing protection functions into service.

Before commissioning, verify protection settings against the feeder protection study and test the configured trip, alarm, measurement, communication, and interlocking functions. Where conventional instrument transformers are used, verify polarity, phase identification, and circuit continuity before applying operating voltage.