scope:

This specification applies to all new impedance protection relays installed on the D.C. Electrified Lines.

Purpose

This specification states the requirements for the design, manufacture and testing of an impedance protection relay for use in association with new or existing 650/750 V d.c. track feeder circuit breakers. When the relay is installed on existing switchgear, as a replacement for an existing protection device, this specification shall also apply to circuit breaker operation, wiring modifications external to the relay and accessories.

The document is to be read in conjunction with the relevant procurement specification.