Summary of a Guide for the Protection of Wire Line Communications Facilities Serving Electric Power Stations

Wire line communications facilities serving electric power stations often require special high voltage protection against the effects of fault produced Ground Potential Rise and/or Induction Voltages. Some of the communications services are used for control and protective relaying purposes and may be called upon to perform critical operations during periods of these faults. This constitutes a major problem in the design of the communications system since power faults usually result in the introduction of interfering voltages and currents into the communications circuits just at the time when the latter is most urgently required to perform its function. Effective protection of any wire line communications circuit requires coordinated protection on all circuits.