Wiring new ceramic hob and oven

[funkwars]

Hi all - I'm replacing an existing freestanding electric oven with separate electric hob and oven.

The hob is rated 6.0Kw -- and the oven is has a max output rating of 3.65Kw.

It's on a 30A circuit that uses 6mm t+e to the cooker control unit and then on to the cooker connection point using the same 6mm2.

I want to supply both appliances from the same isolator - hence my questions:

Can the supply/cable handle both appliances?

Can I supply the oven using a switched fused spur next to the cooker - if so what cable should be used between the isolator and spur, the which fuse and cable between the spur and oven?

Also, I'm considering changing the existing cooker isolator switch to one that has a plug socket included - will this have any implications?

Thanks in advance
Ken

 

[Chri5]

6.0 kW + 3.6 kW = 9600w / 230v = 41.7 amps then your intending to use a kitchen plate with socket so add 13 amps.

So will a 30 amp fuse handle a potential load of 54.7 amps, well maybe.

Diversity applies.

Cooking appliances should have the 1st 10 amps + 30% of the remainder of rated current + 5 amps for the socket.

So 6.0 kw / 230v = 26 amps---> 10 amps + 30% (8 amps) = 18 amps
So 3.6kw / 230v = 16 amos----> 10 amps + 30% (2 amps) = 12 amps
Socket 5 amps.

So with socket in cooker outlet NO, without socket in outlet just about okay.

I could add in that the 6mm cable if run with other cables, in insulation, buried in plaster, is aged could all have an impact on it's ability to run both hob and oven at full tilt.

Personally I'd run a new 10mm, but then that wouldn't cost me (other than time)

 

[ericmark]

It is likely that you can feed your new stuff from old supply even though it needs more than 30A with everything switched on.

However it is likely to cost less than £100 (Fee to LABC for Part P) to have a registered electrician connect this up so it is uneconomic to DIY.

With so many other items like RCD protection likely to have a bearing then seems easiest is to ask the electrician you have selected to do the work.

 

[ColJack]

you have a peculiar way of doing diversity there chri5..

if it was all in one box you'd only do the calc once..
doing it your way your up to 25A straight off anyway..

I make it 24.5A

 

[Chri5]

you have a peculiar way of doing diversity there chri5..

I make it 24.5A

I know I do, and I know it's a bit OTT- but ceramic hobs v ovens- I treat them as BOTH being main cooking appliances and both working to 10a + 30%.

What would you do / do do Easy when the hob is gas, but we both know the hob will have all 4 rings used and should diversity be applied to it ?

Pub beckons- catch up later

 

[ColJack]

but how is it any different to an all in one cooker..

all 4 rings can be used on that at the same time as the oven, but you only allow 10A + %30 for diversity there..

 

[Chri5]

Show me an all in one cooker that takes 9.6 kW

All in ones don't tend to have ceramic + double ovens do they

 

[ColJack]

Show me an all in one cooker that takes 9.6 kW

All in ones don't tend to have ceramic + double ovens do they

what world do you live in?
of course they do cookers with ceramic hob and double oven..

and if you add the spec up on this, the nyou get...
2.0 + 1.5 + 1.5 + 1.0 = 6KW for the hob..
now.. top oven is 1.5KW ( or 2.0KW for the grill ), and the main oven is 1.8KW.. which is 3.3KW...

so 6.0 + 3.3 = 9.3KW.. ok so that's 300w short.. but if you put the grill on instead of the top oven then you get 9.8KW.. and there's the fan and light to add to that yet..

 

[ban-all-sheds]

Show me an all in one cooker that takes 9.6 kW

All in ones don't tend to have ceramic + double ovens do they

what world do you live in?
of course they do cookers with ceramic hob and double oven..

And even if they didn't, what difference would it make? A hob is a hob - you can't significantly reduce the power of the rings or it'll be nbg...

 

[ban-all-sheds]

I know I do, and I know it's a bit OTT- but ceramic hobs v ovens- I treat them as BOTH being main cooking appliances and both working to 10a + 30%.

What would you do with those modular hobs?

If there were two of these:

would you do 2 lots of 10A + 30% of remainder?

 

[funkwars]

Thanks for the replys - and interesting diversity issues!

To be on the safe side I will omit the socket on the cooker plate.

I'm chasing out for the boxes and trunking in advance of my electrician hard wiring the appliances. So trying to buy some time.

The hob will obviously be wired directly to the plate -- will a 13 amp FCU spured from the cooker plate suffice for the oven then (using 6mm2)?

Thanks