ABB RED670 2.1Engineered for reliable phase-segregated current differential protection across two to five line terminals, the ABB RED670 2.1 IEC combines high-speed fault clearance, robust communication redundancy, and integrated backup distance protection within the Relion 670 series.
Product Overview
The RED670 is a dedicated line differential protection IED (Intelligent Electronic Device) designed for the protection, control, and monitoring of overhead lines and cables in transmission and sub-transmission networks. As part of ABB’s Relion 670 series, product version 2.1 supports conventional and digital current measurements from geographically separated stations, making it suitable for multi-terminal line configurations where absolute selectivity is required.
The specific ordering code referenced—B32X00-B10B11B21C24P02-B1X0-D1AD1AD1-BA-XE—aligns with the customized B32 configuration, which supports multi-breaker arrangements with single-phase tripping, providing flexibility for complex busbar and breaker-and-a-half topologies.
Differential Protection Core
The primary protection function is phase-segregated current differential protection (87L), which offers excellent sensitivity for high-resistive faults and secure phase selection. The IED accommodates up to six stabilized current inputs per phase, enabling application on multi-breaker arrangements in three-terminal applications or up to five-terminal applications with single-breaker layouts.
For applications where transmit and receive times may differ across communication channels, the optional built-in GPS receivers provide precise time coordination. Alternatively, the echo method allows operation without GPS clocks in conventional configurations. Charging current compensation further enhances sensitivity on long overhead lines and cables.
Communication and Redundancy
Inter-IED communication is based on the IEEE C37.94 standard and can be duplicated for critical installations requiring redundancy. The communication link is continuously monitored, with automatic switchover to a standby link possible after a preset time. Eight channels are available for intertrip and other binary signals between terminals.
The optional LDRGFC additional security logic enhances protection security during abnormal communication conditions or unspecified asymmetry in the link. It comprises four sub-functions—phase-to-phase current variation, zero sequence current criterion, low voltage criterion, and low current criterion—reducing the probability of maloperation while maintaining sensitivity to evolving faults and high-impedance conditions.
Integrated Backup and Control
A full-scheme distance protection function (quadrilateral characteristic, ZMQPDIS/ZMQAPDIS) is included to provide independent protection in parallel with the differential scheme in case of communication channel failure. Individual settings for resistive and reactive reach per zone offer flexibility for backup protection of transformers connected to lines of varying types and lengths.
The IED also supports single-, two-, and three-phase auto-reclose with priority circuits for multi-breaker arrangements, synchronism check, and a comprehensive suite of backup overcurrent and voltage functions. Disturbance recording and fault location enable independent post-fault analysis, with the recorder displaying remote station currents time-compensated for measured communication delays.
Application and Compliance
The RED670 is suitable for both new installations and the refurbishment of existing schemes. It supports IEC 61850 station communication, including process bus sampled values via IEC 61850-9-2LE, and is compatible with PCM600 engineering tools for configuration and testing. With its wide application flexibility and robust communication architecture, the RED670 2.1 remains a trusted solution for critical line protection in high-voltage networks.
