Back-up Protection

Basic Principles—Precautions for Reliability Remote Back-up—Local Back-up—Relay Back-up—Breaker Back-up—a.c. Supplies—d.c. Supply
  • A. R. van C. Warrington


The function of a protective relay is to operate in response to a fault on a power system so as to minimise the damage to equipment and the interruption to service by opening only those breakers which will isolate the faulty circuit from the power source.


Circuit Breaker Potential Transformer Current Transformer Protective Relay Local Relay 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 106.
    Warrington, A. R. van C. ‘Back-up Protection’, C.I.G.R.E., Paris, 1960, Report No. 334, Section III.Google Scholar
  2. 107.
    Kennedy, L. F. and McConnell, A. J. ‘An Appraisal of Remote and Local Back-up Relaying’, Conferences Paper A.I.E.E., Paper No. 57–560.Google Scholar

Copyright information

© Albert Russell van Cortlandt Warrington 1968

Authors and Affiliations

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

Personalised recommendations