The paper represents further work on phase-comparison techniques by the same author. Efforts to shorten fault clearance times are reported. The basic theory and principle of operation of a new technique of symmetrical phase-comparison for use either in phase-comparison carrier or distance protection schemes is outlined; this is defined by the no-time-delay measuring technique, in which the comparator can detect the instant of fault inception when the phase displacement between the two relaying signals exceeds the trip angle of the system and delivers a trip issue with no time delay. One of its most important advantages is the possibility of minimal fault detection times over the whole of the area covered by a particular relaying characteristic. An example is given of the application of the comparator to a mho characteristic distance relay (90° trip angle) for the protection of a typical 500 kV double-circuit transposed line section of 100 km length. The relay circuitry is described. Steady state and dynamic fault tests were performed using the protective gear test bench. The results confirm the validity of the measuring concept.