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Hob spur for socket
I am having a new hob and oven put in to my kitchen. There is a hob hard wire point 32amp to an isolating switch on the wall and a normal double socket for the oven 13amp, but we won't be hooking it up to the isolating switch as well, but we don't want the wall touching. He says he can spur off the hob point and put in a single socket, so when we cut off the isolating switch, it cuts off both. Can he do this as it's a 32amp supply to a 13amp socket?
The oven has a plug on it that is why its going to a 13amp socket
To connect a 2.5mm standard socket cable directly to a 6mm 32amp cooker circuit without adequate fusing down is not permitted under BS7671:2008. As the 2.5mm cable to the socket is not adequately protected from overload current and has a maximum rating of around 23-25amps. Therefore such an approach can not be legally signed off under part P of the building regulations.
I would not disagree with Rockers, but the new spur can not be concealed behind the oven and so must be mounted above the worktop or in an adjacent cupboard such that it is readily accessible for isolation and switching purposes.
Either way, the alterations will need to be certified and notified to building control under part P of the building regulations. You need to be very careful as it's the householder that picks up the £5,000 fine if this is not done.
Answered 2nd May 2013
Actually this can be done if he uses a cable with current carrying capacity to supply the spur 4mm sq cable should be fine, but I would use 6mm sq to the supply the spur, then you can use 2.5 mm sq to come out the spur to your oven.
Answered 2nd May 2013
interpretaion counts for a lot. If its ok to run a sinle or double socket outlet on an unfused spur on a 32A protected ring/radial then this applies to the circuit described above so it ok to spur to a single socket in 2.5 T+E but as stated the socket needs to accessible (in adjoining cabinet/above worktop)
If spuring to multiple sockets then 4mm cable would be the requirement.
Above is as stated in BS 7671:2008(2011) Appendix H2.4
Just my interpretation of the regs as I read them.
P.S I would have run the above spur in 4mm T+E
Answered 6th May 2013
Not sure if I'm reading it right:
A) If the Hob isolator feeds the electric hob then ideally this should be kept dedicated to the electric hob.
B) The hob isnt connected (ie, gas hob) and you are using the isolator to feed a single or twin socket for the oven, then using 2.5mm cable would be fine on a 32A circuit as that single or twin socket is never likely to pull more than 13A or 26A (2.5mm is rated around 27A)
Answered 9th May 2013