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SP - single-pole, DP - double pole. What does this mean?

Discussion in 'Electrics UK' started by doh....., 14 May 2007.

  1. doh.....

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    I am about to replace some sockets and switches in my house. I have noticed that they come either SP or DP. What does this mean? Which one is better?

    Please advise

    Many thanks
     
  2. afswift

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    Refers to the switching,

    single pole just switches live

    double pole switches both live and neutral
     
  3. davy_owen_88

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    Single pole switches disconnect the phase conductor only, while double pole disconnects both phase and neutral.

    There is not requirement that you use DP switches but I would recommend it anyway.

    *bah!*
     
  4. afswift

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    beat me to it!!
     
  5. JohnD

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    yes, DP is preferable

    However, more important still is buying a decent brand.

    Crabtree, MK, MEM are all good.

    Cheap ones are usually cheap for a reason.

    What do you have in mind, and how many? Electrical wholesalers are often cheaper if you are buying a bunch.

    Fancy brass and chrome ones are always a lot more more expensive than white.
     
  6. doh.....

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    Was looking at Crabtree or MK. screwfix seem reasonable. I prefer white because there cheaper but my partner would prefer brushed stainless. Let the battle commence.

    Thanks for the help
     
  7. festa

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    T.T earthing systems?
     
  8. Adam_151

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    I understand why you should say that, but you're wrong, removeing the plug is allowed as isolation and breaks both poles, the switch is just a functional switch (although some of the newer ones might be approved as isolators... 3mm separatation and all that)
     
  9. festa

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    Hi Adam..
    Yes a socket outlet can be isolated by switching off and removing the plug but when you have an FCU inline how can you disconnect the neutral then?
    Just check OSG page 34 note(ii) for me and let me know im not misunderstanding it as whenever i carry out work on an installation forming part of a T.T earthing system i always replace/install double pole switchgear.
     
  10. JohnD

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    DP FCU of course

    [​IMG]
     
  11. festa

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    Hiya John..
    So your saying in a T.T earthing system DP switches are to be used?
     
  12. JohnD

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    dunno.

    I was just saying, if you want to use an FCU, it can be a DP one.
     

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