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Wiring a bathroom mirror cabinet (best practice)

Discussion in 'Electrics UK' started by DaveyH, 9 Oct 2015.

  1. DaveyH

    DaveyH

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    Hi,

    I'm in the process of installing the wiring for a new bathroom mirror cabinet in our new bathroom. The cabinet is rated IP44. It has LEDs on the front, a demister pad, a light inside and a shaver socket inside. There is a small rocker switch near the shaver socket to turn it on and off. The demister pad and LEDS are turned on and off by moving your hand near an infrared sensor.

    The instructions that came with it, say to install it to the latest IEE wiring regulations, and then just show the flex cable on that protrudes from the back of the cabinet being wired up to a bit of choc bloc, here is the picture.

    [​IMG]

    To get power to the cabinet I intend running a spur from the bathroom light.

    Questions.

    Q1. Can I simply spur straight off the bathroom light or would it be better to use an FCU or switched FCU or some other type of isolation?
    Q2. The cabinet is rated as 300W, so will 5 amp choc block be ok?

    Background. Our house was fully rewired to 17th Edition a few years ago (we still even have the part P certificate).

    Thanks in advance.
     
    Last edited: 9 Oct 2015
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  3. EFLImpudence

    EFLImpudence

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    Yes.

    It's up to you. No requirement.

    Yes, 3A would do.

    The circuit should be protected by an RCD, then - as it must be.
     
  4. DaveyH

    DaveyH

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    Thanks for the super fast reply and yes there is RCD protection on the Consumer unit.
     
  5. sparkwright

    sparkwright

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    If you 'spur' from the bathroom light, check first there is a permanent live there.

    This way you won't have to have the main light on in order for the mirror light to work.
     
  6. winston1

    winston1

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  7. winston1

    winston1

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    FCUs are not used or required on lighting circuits.
     
  8. ban-all-sheds

    ban-all-sheds

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    Whoever arranged that has clearly not heard of the old adage about keeping both hands behind the tool.
     
  9. bubachuba

    bubachuba

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    hi. pedantic but.... if the lighting circuit was on 10 amp protection and the manufacturer of the cabinet requires, say 3, (admittedly the OP hasn't stated that they do) then an FCU would be an ideal way to achieve their requirements.
     
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  11. ban-all-sheds

    ban-all-sheds

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    Or one could

    1) Ask them to confirm in writing that they have built something so flaky and feeble that it has to rely on the external circuit protective device (which is not what it's for) to be safe, and to explain why, and in what way it is unsafe.

    2) Think about whether one wants to install electrical items made by a company with such an attitude to safety and quality, even with a 3A fuse.
     
  12. bubachuba

    bubachuba

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    BAS - i take your point, although i was just trying to make a point that in cases where the manufacturer asks for their (crap!) stuff to be protected by something other than the protection at the origin of the circuit: an FCU will achieve this. First things comes to mind is bathroom extractor fans.
     
  13. ban-all-sheds

    ban-all-sheds

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    I know it is quite common.

    And the thing to do is to challenge them and ask them to explain why they are making such flaky products.
     
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  14. winston1

    winston1

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    You could also ask them if they also sell it in the rest of Europe where FCUs are not used and lighting circuits are protected at 16amp. And if so what do they advise there.
     
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  15. winston1

    winston1

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    You could also ask them if they also sell it in the rest of Europe where FCUs are not used and lighting circuits are protected at 16amp. And if so what do they advise there.
     
  16. bubachuba

    bubachuba

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    Agreed.
     
  17. ban-all-sheds

    ban-all-sheds

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    Hmm.

    Both of those questions might be answerable for items with a multi-language instruction/installation manual.
     
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