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Sub-Board - Second Consumer Unit

Discussion in 'Electrics UK' started by FRAN1870, 7 Nov 2018.

  1. FRAN1870

    FRAN1870

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    Hello,

    I need to rewire my kitchen and utility.... I need to run the usual services Kettle, dishwasher, tumble, washing machine and sockets etc but also the possibility of two electric ovens.

    The only real access I have to run any cables back to the main board is really getting a bit crowded with gas pipes and other wiring / central heating pipes etc ( everything crosses along and down a very small corridor). Is the crowding a problem? I'm also conscious of drilling too many holes in the joists!

    Instead of running multiple cables can I instead run one 16mm twin and earth cable and have a second consumer unit in the utility and rewire a ring main and some lighting from there?

    Will I be able to run the ovens from this second board?

    p.s there is a 10mm cable from a soon to be redundant electric shower that I could really easily use for this run but I assume this won't be big enough if we go for electric ovens?

    TIA
     
  2. AndyPRK

    AndyPRK

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    Using the 10mm like that sounds a great idea.

    Try and keep lighting seperate if sensible.
     
  3. chivers67

    chivers67

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    You need to work out exactly how much Demand you'll have for the whole Kitchen, Electric Ovens don't always take much Current - depending on what they are?
     
  4. FRAN1870

    FRAN1870

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    Well from the 250 ovens listed on the Currys website only two of them are showing 32amp, most say 13amp so I assume I'll have 2 x 13 or at a worse case 2 x 16amp

    Say something like this one x 2 which is 3.2KW ... so 6.4KW / 230v = 27amps which we could downrate a bit in the board if required?

    https://www.currys.co.uk/gbuk/house...ectric-oven-stainless-steel-10164699-pdt.html

    So would running the whole kitchen and utility on a 10mm feed to the new board be feasible if we stick to 13amp ovens?
    Or should I just run the 16mm? I do have another option of chasing the 16mm into the wall but I thought that would downrate the cable to roughly the same as 10mm anyway?
     
  5. winston1

    winston1

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    Ovens don't continuously run full power, they cycle on and off. Even if you are using both most likely one will be cycled off when the other is cycled on.
     
  6. FRAN1870

    FRAN1870

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    So could that be signed off under part p?

    I’m planning on running the cables myself and getting a sparky to check and sign it all off
     
  7. flameport

    flameport

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    That is not a valid method for notifiable work.

    Options for notifiable work:
    1. You notify first and then do the work, either direct to building control or via a third party certifier.
    2. Registered electrician does the work and the notification.

    16mm² is massively oversized for a normal kitchen/utility.
    Entire houses are connected with less.
     
  8. FRAN1870

    FRAN1870

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    I thought it was overkill hence the question about using the 10mm if I decide to replace the shower.

    I don’t see me running the cable and them hooking it up any different to a registered sparky using an apprentice?
    As long as he can see what I’ve done and check the routing etc? I’m literally just first fixing to keep the cost down?
     
  9. chivers67

    chivers67

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    I'd contact a few local Electricians and discuss your plans together. They'd probably be happy if they could see the whole route.
     
  10. ban-all-sheds

    ban-all-sheds

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    Maybe you don't.

    But it is.

    I being the person responsible for the design, construction, inspection & testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the design, construction, inspection & testing hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2015 except for the departures, if any, detailed as follows:

    You aren't even doing the design - you're asking a bunch of strangers on an internet forum to do it for you, but even if you were, when you present it to an electrician, how can he sign a document to say that he was responsible for it?

    If you install the cables (construction) and present that work to him, how can he sign a document to say that he was responsible for it?

    Plus with Building Regulations certification, he will be signing to say that the work he did complied.

    Often, legally, it is a business which signs these declarations (they are, after all, legal entities), and it is the firm which is taking responsibility for things done by employees. Apprentices are employees. You are not.

    You might find an electrician prepared to direct and supervise you work to the extent that he is happy to say that he was responsible for it, but for that to work that has to be agreed before any work starts, and he really has to be genuinely in charge. Your current plan is a non-starter.
     
  11. bernardgreen

    bernardgreen

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    does not mean that the person actually carried out the work for which he or she has accepted responsibilty.
     
  12. Taylortwocities

    Taylortwocities

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    That is the implication, it allows the person signing to oversee the functions, but not retrospectively - as expected by the OP.
    As advised above, the OP might be able to find a tame electrician who might allow him to run cables, etc, under his direction.
     
  13. ban-all-sheds

    ban-all-sheds

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    I being the person responsible for the design, construction, inspection & testing of the electrical installation (as indicated by my signature below), particulars of which are described above, having exercised reasonable skill and care when carrying out the design, construction, inspection & testing hereby CERTIFY that the said work for which I have been responsible is to the best of my knowledge and belief in accordance with BS 7671:2008, amended to 2015 except for the departures, if any, detailed as follows:
     
  14. JohnW2

    JohnW2

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    That would certainly seem to be true of the two references to "responsible" in the declaration. However, the middle of the three sections in the declaration which were recently highlighted is a bit difference, since it reads (with my modification to the highlighting) ...

    "I ....... , having exercised reasonable skill and care when carrying out the design, construction, inspection & testing ..."

    ... and I can see that it could easily be argued that "when carrying out" implies that the person signing the declaration has actually undertaken the three tasks mentioned.

    Kind Regards, John
    Edit: too slow at typing again!
     
  15. bernardgreen

    bernardgreen

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    Take that to the extreme and there would need to be several signatures on the certification unless all the work involved in the whole project was carried out by just one person.

    No more team work.
     
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