MONITOR FOR SIGNAL QUALITY IN A PROTECTIVE RELAY SYSTEM

摘要

A monitor for signal quality in and a protective relay system which utilizes both AC (AGC) and DC (GCV) signals from the receiver agc stage (42) to monitor a plurality of different signal parameters. A signal (VX) responsive to the noise in the communication channel (40) which transmits at least one of the protective relay signals (VR) used in a protective relay comparison function (36 min ), is also used in the trip circuits (132) of the associated circuit interrupter (16) to continuously adapt or modify the trip level in response to channel noise.