cooker and hob install

[sparky71]

I have been called to do the electrics for a couple who want a induced as well keeping their existing electric oven, here's the details oven 5.2kw induced hob 7.2kw a toal of 12.4kw, after working the design current and diversity out I have 29amps, at the moment it has a 6mm cable with socket outlet incorporated cooker isolator, the board is downstairs in the basement and all the walls have been tanked and sealed with bubble wrap, normal case fog a basement, what i am asking is with not knowing how much of the cable in the wall is insulated, do I stick with the 6mm or upgrade to 10mm, in which the customer wants in trunking on the surface of the sealed wall, all suggestions welcome

 

[Technician]

Without the books to hand, and maybe more than 0.5 m

inside insulation, you could be looking at 10 mm at least.

 

[sparky71]

I have been called to do the electrics for a couple who want a induced as well keeping their existing electric oven, here's the details oven 5.2kw induced hob 7.2kw a toal of 12.4kw, after working the design current and diversity out I have 29amps, at the moment it has a 6mm cable with socket outlet incorporated cooker isolator, the board is downstairs in the basement and all the walls have been tanked and sealed with bubble wrap, normal case fog a basement, what i am asking is with not knowing how much of the cable in the wall is insulated, do I stick with the 6mm or upgrade to 10mm, in which the customer wants in trunking on the surface of the sealed wall, all suggestions welcome

 

[Theorysparky]

how long is the run ????

 

[ProDave]

If your borderline, get rid of the socket and replace it with just a cooker switch. That saves you 5 amps of allowance.

 

[Doc Hudson]

As you say it is a tanked and sealed basement does that mean it is an older property. If it is could you assume less insulation than if it were a new build. Also it may be worth considering if the existing cable has any signs of deterioration or is it still in good condition. low IR, high R1+R2, visible overheating signs of the insulation at the terminations..

Doc H.

 

[Theorysparky]

Good point

then it gives him almost 50% diversity for the cable

but if its a long run i would put 10mm in

not enough info at the mo

 

[m4tty]

Is this a duplicate thread I'm sure I read this yesterday ?

 

[Theorysparky]

dont know

 

[sparkytim]

On site guide pg 59 (current Green version) gives 49 mtrs max length for a 6mm 0n 32 A type B MCB with RCD protection TNS or TNCS.even if thermal insulation an issue (Installation method 102)

 

[Doc Hudson]

Is this a duplicate thread I'm sure I read this yesterday ?

It was, but they are now merged.

Doc H.

---------- Post Auto-Merged at 11:57 ---------- Previous post was made at 11:54 ----------

I have been called to do the electrics for a couple who want a induced as well keeping their existing electric oven, here's the details oven 5.2kw induced hob 7.2kw a toal of 12.4kw, after working the design current and diversity out I have 29amps, at the moment it has a 6mm cable with socket outlet incorporated cooker isolator, the board is downstairs in the basement and all the walls have been tanked and sealed with bubble wrap, normal case fog a basement, what i am asking is with not knowing how much of the cable in the wall is insulated, do I stick with the 6mm or upgrade to 10mm, in which the customer wants in trunking on the surface of the sealed wall, all suggestions welcome

I have been called to do the electrics for a couple who want a induced as well keeping their existing electric oven, here's the details oven 5.2kw induced hob 7.2kw a toal of 12.4kw, after working the design current and diversity out I have 29amps, at the moment it has a 6mm cable with socket outlet incorporated cooker isolator, the board is downstairs in the basement and all the walls have been tanked and sealed with bubble wrap, normal case fog a basement, what i am asking is with not knowing how much of the cable in the wall is insulated, do I stick with the 6mm or upgrade to 10mm, in which the customer wants in trunking on the surface of the sealed wall, all suggestions welcome

The two duplicate threads posted in different forums have both been merged into this single thread. Can member please ensure they only post one copy of a question. if you think you want it moved to another area, PM one of the Mods or Admin and we shall move it. Thank you.

Doc H.

 

[sparky71]

Sorry about duplicate thread, just getting used to the forum, anyway, by knocking the skt on the head would reduce it to 24amps, but then the customer wouldn't have a socket in that wall, the run is 10mtrs, approx, pme, I have discussed with a few other forrums. They are suggesting a circuit for both oven and hob, not sure if that is overkill, if I fit 10mm that's fine and will full fill all aspects regs wise, but it's size and inflexibility just want to cover all alternatives

 

[Theorysparky]

Sparky mate

how about this then....

existing cct use for the oven and socket 5.2kw gives you 19.2 amps sorted

new cct to feed hob 7.2 kw gives you 17.1 amps 4mm or 6mm if its all in trunking,,,,,,,i would go 6mm

job done

 

[hxsarge]

throw a 2.5 in and pretend its in a swirling vortex and burn your regs book? :Salute

or just always go on the larger size just in-case.... oh and still burn your regs!

 

[sparky71]

I think it's the safe option, 2 X 6mm ccts 1 X existing and 1 new one, one for the oven one for the hob

 

[ProDave]

Not like a customer that phoned me yesterday.

He wants to move his cooker, but doesn't know where to yet, as he's still planning his new kitchen.

so "could you come and disconnect it from the wall and just put it on a 13A plug please?" :slap