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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?
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  • 0
    Bear in mind that a flex's cpc is the same CSA as its line conductors, while a 6mm T&E only has a 2.5mm cpc. So a L-E short will have roughly the same heating effect on a 2.5 flex's cpc as on the 6mm T&E's cpc.


    The overload situation is more complex, as the manufacturer gives no indication as to what the maximum current the electronics of the unit will allow it to sink. Will it allow all 4 rings on boost (54A for 4 mins, then 50A for a further 6 minutes), or will it limit it to 31A (7.35kW) at all times? Who knows? What's the min/max OCPD required by the device? Who knows?
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  • 0
    Bear in mind that a flex's cpc is the same CSA as its line conductors, while a 6mm T&E only has a 2.5mm cpc. So a L-E short will have roughly the same heating effect on a 2.5 flex's cpc as on the 6mm T&E's cpc.


    The overload situation is more complex, as the manufacturer gives no indication as to what the maximum current the electronics of the unit will allow it to sink. Will it allow all 4 rings on boost (54A for 4 mins, then 50A for a further 6 minutes), or will it limit it to 31A (7.35kW) at all times? Who knows? What's the min/max OCPD required by the device? Who knows?
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