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Cable Diversity for Induction Hob

Former Community Member
Former Community Member
Hi all,


I have been tasked with wiring an induction hob, and I’m fairly new to install work on my own having just qualified myself and venturing out on my own. 


The Hob is rated at 7.35kW.

In my head, and applying the cable diversity factors-

7350w divided by 230v =31.95amps.

Take off the first 10amps =21.95amps

21.95x30% = 6.58amps

6.58amps+10amps =16.58amps Total.


Plus 5amps if there is a 13amp socket involved, which there isn’t in this case.


so with that in mind, I’d be fine wiring the circuit with reference method C (clipped direct) in 2.5mm T+E right??! Although saying that, my thoughts are to wire using 6mm T+E just in case future appliances vary! 

does this seem logical or should I just keep it as a 2.5mm circuit on a 20amp MCB.


any advice would be greatly appreciated. Let me know your thoughts?
Parents
  • The hob may well leak up to 10mA or so, and a '30mA' RCD fires anywhere between 15mA and 30mA,  so it does not leave much allowance for other electronic devices plugged into the ring - computers and monitors etc can clock up  a few mA of earth leakage each, as can the lots of the little switch mode units that supply LED lights instead of traditional transformers and so on.

    You may be all right on a shared RCD, but I know a couple of colleagues, admittedly in larger more IT heavy houses, where a dedicated RCBO for the hob was eventually needed as the solution to random tripping.

    The RCD may be nearer the upper limit, or it may not, and I cannot see the set-up and how much electronics there is in the house already.


    M.
Reply
  • The hob may well leak up to 10mA or so, and a '30mA' RCD fires anywhere between 15mA and 30mA,  so it does not leave much allowance for other electronic devices plugged into the ring - computers and monitors etc can clock up  a few mA of earth leakage each, as can the lots of the little switch mode units that supply LED lights instead of traditional transformers and so on.

    You may be all right on a shared RCD, but I know a couple of colleagues, admittedly in larger more IT heavy houses, where a dedicated RCBO for the hob was eventually needed as the solution to random tripping.

    The RCD may be nearer the upper limit, or it may not, and I cannot see the set-up and how much electronics there is in the house already.


    M.
Children
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