Overcurrent and earth fault protection

  • C. Christopoulos
  • A. Wright


Fuses are a very satisfactory form of protection for the lower voltage and current sections of power networks because their operating time/current characteristics are similar in form to the withstand time/current characteristics of the circuits they protect. Their use enables circuits to be kept in service until times when faulted or overloaded parts of a network must be disconnected to ensure that healthy equipment does not suffer consequential damage.


Current Transformer Fault Current Earth Fault Correct Discrimination Load Circuit 
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Further Reading

  1. Part 0 : 1982 General Introduction and list of parts.Google Scholar
  2. Part 1 : 1982 Information and requirements for all protection relays. Google Scholar
  3. Part 2 : 1982 Requirements for the principal families of protection relays.Google Scholar
  4. Part 3 : 1990 Requirements for single input energizing quantity relays.Google Scholar
  5. Part 4 : 1984 Requirements for multi-input energizing quantity relays.Google Scholar
  6. Part 5: Supplementary requirements.Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 1999

Authors and Affiliations

  • C. Christopoulos
    • 1
  • A. Wright
    • 1
  1. 1.University of NottinghamNottinghamUK

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