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What is the function of Switchgear in Substation?

  1. Jan 28, 2014 #1
    I think its main function is to reduce arc flash.
    But I want to know how it is connect with the transformer before or after.
    Can any one explain it through the block diagram?

    If HV power lines enter in the substation first it connect to which one and after that which one ? [Switch gear, Transformer].

    Is the input and output voltage & current of switchgear remains the same?
  2. jcsd
  3. Jan 29, 2014 #2


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    No member here on Physics Forums will spoon-feed knowledge to others. You must show some effort to find the answers first. Then, if you get confused, or don't understand some details, come here and ask. Members here are always ready and willing to help any true "searcher".

    I suggest you open "Google" and enter the search terms "function of switchgear in substation" and begin your lessons.

  4. Jan 31, 2014 #3
    hello, take a look on this link:

    http://www.energy.siemens.com/hq/pool/hq/energy-topics/power engineering guide/PEG_70_KAP_03.pdf

    you have some typical single line diagrams for substations.

    main link to Guide:


    main functions are to provide automated fault protection, manual switching of power lines and devices, and to provide safety conditions (isolating, grounding) on equipment before service.
  5. Feb 6, 2014 #4
    I've worked on these. It's really just a simple switch. Electrically it's no different than a light switch in your home. It typically has more poles of course for 3 phase power. Some of them can also break the neutral line as well (4 pole single throw).

    What sets it apart is that switch gears are designed for large currents and voltages. The conductors in the switch are larger so that they can handle larger currents. Insulation is more robust to account for higher voltages. They also have a gear action and springs for the actual switching. A switchgear either slams shut or slams open. They're loud. It can take a little muscle to open and close a big switchgear.

    Switchgears are typically installed immediately after the step-down transformer and before the breaker panel in commercial, industrial, or distribution services. The switch allows you to completely deenergize a service for maintenance purposes.
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