Design of a generic range of distance relays

The design of the described generic range of distance relays differs from most other new designs in that it uses multiprocessor hardware in an evolutionary way, making maximum use of the experience gained with earlier generations of distance relay. Microprocessors have been employed in the measuring circuits to produce a direct software equivalent of the hardware phase comparator used in earlier generations, having an operating principle which has been fully documented in previous literature. The principle uses analogue preconditioning and digital processing to achieve a fast operating time while preserving immunity from noise