Effects of Noise on Transfer-Trip Carrier Relaying

A test method is described for the measurement of the probability of error due to noise in transfer-trip (TT) relaying using power line carrier. Noise levels recorded on 230-kV carrier installations are given to permit the interpretation of the measured error probabilities in terms of reliability and security. Three possible applications of the method are demonstrated: 1) finding the required biasing for frequency-shift-keying receivers, 2) preservice checking of transfer-trip channels, and 3) comparison of different transfer-trip systems.