Three ovens! Yes three....

[Benway]

Hi.

Myself and my wife have managed to come up with a three oven solution to a problem that never existed She wanted two separate ovens, i wanted a warming draw, but could actually buy another oven for half the money, so went for that.

So we now have three ovens to connect, doing the maths, it's theoretically possible to wire these all back to the existing 6mm oven point. But is it physically possible/best practice. Oven details below.

Cheers.

 

[EFLImpudence]

So we now have three ovens to connect, doing the maths, it's theoretically possible to wire these all back to the existing 6mm oven point. But is it physically possible/best practice.

Well, it does depend on what rating the other two are but generally, yes, it will be fine.

You can connect 15kW to a 32A, 6mm² circuit - possibly more.

2350W is around 10A; not 13 - so could be on a plug.

 

[Benway]

All three ovens are the same. So looks like our maths matches. Sweet.

 

[ban-all-sheds]

But is it physically possible/best practice.

If it were not best practice, what would people do who bought one of those large range cookers with 3 ovens and a multi-zone hob?

As for physically possible, you will struggle to get 3 x 6mm² cables into the terminals of a cooker outlet plate, and possibly 2 x. Might be a good idea to put a dual one behind each oven so that you can daisy chain from one to the other and never need more than one cable per terminal.

 

[Benway]

Oooo, never seen ones of those before. Would it need to be 3 x 6mm though, the oven uses 10A max. So would it not be possible to use some heat resistant flex like https://www.tlc-direct.co.uk/Products/CA1dot5HR3.html ?

 

[John D v2.0]

Deleted

 

[ban-all-sheds]

Are you struggling to keep track of the context of the 5 posts so far?

 

[JohnW2]

Just a heads up, I guess that's atypo, should be 7.5kw, unless you are meaning 15kw of total cooking load or including diversity?

I presume that he means a total 'maximum load' before applying diversity, although the answer is (in the absence of any sockets) nearer to 19kW than 15kW.

In terms of rough maths ... 19kW at 230V is ~83A which, after diversity, is about 32A.

Kind Regards, John

 

[EFLImpudence]

Hence my "possibly more" - I do not know if there is a socket on the switch; and neither do you.

Well, it does depend on what rating the other two are but generally, yes, it will be fine.
You can connect 15kW to a 32A, 6mm² circuit - possibly more.
2350W is around 10A; not 13 - so could be on a plug.

I cannot see anything wrong with what I wrote or what would be a typo.

I presume that he means a total 'maximum load' before applying diversity, although the answer is (in the absence of any sockets) nearer to 19kW than 15kW.

How can 15kW be after diversity?

So, (in the absence of any sockets[sic] or not) I got it right, then - 15kW, possibly more.


I think you are too good at figuring out what people actually mean when they write things wrongly, that you have trouble with things that are written correctly.

 

[ban-all-sheds]

I once read somewhere that the (fl-10)*0.3+10 guidance only applies to cooking appliances ≤ 15kW.

 

[John D v2.0]

Sorry, didn't realise it was a sensitive topic

 

[JohnW2]

How can 15kW be after diversity?

It can't - and that's what I was explaining to JohnD

So, (in the absence of any sockets[sic] or not) I got it right, then - 15kW, possibly more.

Indeed - you got it right, and I would not expect otherwise.

I think you are too good at figuring out what people actually mean when they write things wrongly, that you have trouble with things that are written correctly.

I think you're being too sensitive. I understood and agreed with what you had written and, since you had not responded yourself, explained the reasoning to JohnD - adding that it could be as much as 19kW before diversity in the absence of any sockets.

In passing, I was interested to see that you put "[sic]" after my "sockets". Does this mean that you thought that I used the plural in error and that you interpret the standard diversity calculation as meaning that one has to allow 5A for each and every socket on the circuit? - e.g. if, say, three ovens were each supplied via a 'cooker control unit' with a socket, that one would have to allow 15A for those sockets - so that the maximum before diversity cooker load would be about 33.3A / 7.67kW?

Kind Regards, John

 

[EFLImpudence]

I may have confused the two Johns - apologies.

 

[ban-all-sheds]

if, say, three ovens were each supplied via a 'cooker control unit' with a socket, that one would have to allow 15A for those sockets

That is up to the designer to decide when he exercises his reasonable skill and care....

- so that the maximum before diversity cooker load would be about 33.3A / 7.67kW?

How about 53.3A/12.27kW?

Now there's an interesting exercise for the reader....

 

[Benway]

No Sockets. Just need to find a triple appliance outlet plate and we're mustard! I know these don't exist unfortunately