Directional Pilot Relaying

Basic Principles—Pilot Wire Schemes—Carrier Channel Schemes—Carrier Signal Checking—Future Trends
  • A. R. van C. Warrington


A ‘unit’ form of protection may be used when it is important to clear all faults simultaneously at both ends of the protected section of line, such as when high-speed automatic reclosing is used. For unit protection it is necessary to exchange information about the fault conditions at each end of the protected section and either a pilot-wire or a carrier channel is used for this purpose.


Fault Detector Carrier Signal Fault Current Protective Relay Ground Fault 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Albert Russell van Cortlandt Warrington 1968

Authors and Affiliations

  • A. R. van C. Warrington
    • 1
  1. 1.The English Electric Company LimitedStaffordUK

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