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One & Half Breaker Arrangement - Substation design (Bus Bar Schemes)

  • In this scheme, three circuit breakers are used for controlling two circuits which are connected between two bus bars. Normally, both the bus bars are in service.




  • A fault on any one of the bus bars is cleared by opening of the associated circuit breakers connected to the faulty bus bar without affecting continuity of supply. Similarly, any circuit breaker can be taken out for maintenance without causing interruption. Load transfer is achieved through the breakers and, therefore, the operation is simple. However, protective relaying is somewhat more involved as the central (tie) breaker has to be responsive to troubles on either feeder in the correct sequence. Besides, each element of the bay has to be rated for carrying the currents of two feeders to meet the requirement of various switching operations which increases the cost. The breaker and a half scheme is best for those substations which handle large quantities of power and where the orientation of out going feeders is in opposite directions. This scheme has been used in the 400 kV substations.
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Comments

  1. Unknown8 January 2016 at 14:10

    why is called one & half bus bar

    ReplyDelete
  2. Gulzar25 May 2016 at 09:49

    Very informative article on circuit breaker and how to resolve its ultimate faults, if occurs. I find it very useful. This topic mainly covers electrical-engineering and helpful for all those who are interested in electrical related topic

    ReplyDelete
  3. Gulzar25 May 2016 at 09:52

    fadsfsadfsad

    ReplyDelete
  4. Ziaul Huda22 July 2020 at 23:01

    What is the I configuration and D configuration

    ReplyDelete

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