Oven & Hob

[hoppy]

Hi guys

installing a new hob and oven for my dad tomorrow, exisitng one is outdated to say the least.

Induction hob is 6200W and oven is 2500W.

so calculated 38A for both.

Existing cable is 6mm, so think that is fine.

current set up a bit of a mess!

So from cooker switch I am going to run 6mm to a cooker connection unit for the hob.

For the oven I am going to install a fused connection unit (13 amp) and run 2.5 from it to the oven.

My question is would you spur off the cooker switch or the ccu for the fcu to feed the oven and would you feed the fcu in 2.5mm or 6mm?

Is this acceptable the way I am planning on doing it?

I currently only work commercial so have very ltd domestic experience.

Thanks Guys

Craig

 

[revjames]

I dont see a problem in supplying the FCU in 2.5 and then 2.5 to the oven as its only 2500w. You could either run a separate circuit from the CU on a 16A or even spur from ther ring circuit. The hob being 6200W better off in 6mm and 45A circuit. If they were together on same circuit I'm pretty sure you could apply diversity (ie 10a + 30% of remainder) but running 6mm to the oven would be a bit of an overkill.

 

[tom1]

almost 24 amps with a socket so 32 amp mcb

i would prob run 6mm to cooker switch, 6mm to conection plate then 2.5 for the oven,

 

[Badger]

id take the oven side off the socket circuit as im not a fan of taking it from a 32 amp circuit, and id incorporate into ring main not spur it too....

 

[bengie]

id take the oven side off the socket circuit as im not a fan of taking it from a 32 amp circuit, and id incorporate into ring main not spur it too....

same as really but i'm not fussy about the fcu being on the ring or a spur, i'd rather it on the ring but it depends on how difficult that is.

 

[bengie]

almost 24 amps with a socket so 32 amp mcbi would prob run 6mm to cooker switch, 6mm to conection plate then 2.5 for the oven,

i'm confused, whats 24A?

 

[revjames]

I'm guessing but think he has applied the diversity rule to the total load of your cooker. (10a plus 30% of remainder and add 5a if theres a socket outlet on the cooker switch)

10A + 30% of remainder (28A) is near enough 19A + 5A for the socket = 24A

 

[hoppy]

Thanks guys great advice as always.

So i can go either way, will see what is easiest, but i guess safest to take the oven off the ring if possible.

Thanks again

Craig

 

[ianmacd]

I guess this would also be notifiable work as its fixed wiring in a kitchen .

Ian.

 

[hoppy]

Sorry should have mentioned that, i understand it is notifiable and has to be RCD protected, i am still a trainee but I have passed my 17th edition.

Thanks

Craig

 

[tom1]

I'm guessing but think he has applied the diversity rule to the total load of your cooker. (10a plus 30% of remainder and add 5a if theres a socket outlet on the cooker switch)10A + 30% of remainder (28A) is near enough 19A + 5A for the socket = 24A

yer sorry, thanks for filling in the blanks i can be a bit vague but it had been mentioned in earlier post.

 

[BS3036]

Be aware that the design of induction hobs can be such that diversity cannot be allowed. This results from the 'boost' function. It all depends on the particular design but in general diversity should not be allowed. The manufacturer's instructions should be followed.

 

[PC Electrics]

Sorry should have mentioned that, i understand it is notifiable and has to be RCD protected, i am still a trainee but I have passed my 17th edition.Thanks

Craig

Re-aquaint yourself with appendix 15, item 1.(iii) on page 362 of the BRB.

 

[hoppy]

Thanks PC, I forgot about that little rule.

So I am better to spur off the ccu then or run a 16A radial for the oven?

Thanks again

Craig

 

[PC Electrics]

http://www.scolmore.com/login/product_finder_entry.aspx

search for PRW217 - it's a dual outlet adaptor for cookers. There's also a patress to go with it (PRW218?) if you haven't got a 2G box in the wall. Then use 4mm H07RN-F (http://www.tlc-direct.co.uk/Products/CA4TQ3slash50.html) for the hob and either the same (if the connections will take 4mm) or 2.5mm for the oven. The 2.5 is okay on a 32A MCB just the same as it is for a spur on a ring, only in this case the appliance max load is fixed. No need for the complication of a fused spur.

 

[hoppy]

Thanks PC, great advice and help.

Really appreciate your help.

Craig

 

[Theorysparky]

Be aware that the design of induction hobs can be such that diversity cannot be allowed. This results from the 'boost' function. It all depends on the particular design but in general diversity should not be allowed. The manufacturer's instructions should be followed.

totally agree

but sometimes you need to use common sense

 

[BS3036]

totally agreebut sometimes you need to use common sense

OK, as long as you realise that I said that because only the manufacturer knows whether the design of the hob allows for diversity or not. If they say it doesn't, because they divert every last amp into one ring or other for potentially long periods, then it would be sensible to take them at their word.

In practice, I haven't noticed manufacturer's instructions being good enough to be sure anyway. But there you go...