Is this oven wired correctly?

[Lost Shed]

Just had a new kitchen fitted with a halogen hob, (4 hob- total of 6.5kw) and single fan oven (2.18kw) fitted directly below the hob.
There is a cooker isolating switch on the wall (type with associated switched socket), not sure of cable size but def bigger then
2.5mm ring main cable.

I was suprised to find that switching off the cooker isolating switch only the power to the hob was cut and not the oven. Further
investigation, by pulling fuses at the consumer unit, confirmed the oven was on the ring main circuit. Don't know how the oven is
connected to the ring main (ie plug and socket) or if it's fused but wherever it's connected it's definitely not accessible. The only way I can isolate the oven from the supply is to pull the ring main fuse.

So my questions are :-

1. Could/Should the oven have been connected to the cooker supply circuit, and what size cable should be used taking into account the power of the hob.?

2. If the oven can be connected to the ring main should it be separately fused (ie plug & sckt) and should this isolating point be easily accessible?

 

[felix]

The oven will be 3kW or less and so it can go on the ring main. Possible connection methods are a standard three pin plug in a socket or a fused connection unit. Yours must be hidden behind the oven or maybe in an adjacent cupboard.

There is nothing wrong with this arrangement, though an isolating switch above bench level would have been nice. There is actually a minor disadvantage to putting a readily accessible switch on an electric oven. You only realize this when you get home late, having set your oven timer, and find that all you have for supper is raw meat - because some plonker switched the oven off by mistake!

 

[brumylad]

I am having the same dilema.

Oven instructions say it should be capable of being isolated by means of a double pole switch.

6.5 kw Hob instructions say it should be on a 30 amp fuse, 230v x 30a =6.9 Kw.

Oven is 2.5 Kw, so ok to spur off ring main but it seems 2 separate double pole switches are needed by rights ????

 

[shaggy]

Ok the oven can be connected to the ring if load is no more than 3kW, but is that the kitchen ring or downstairs house ring? Look at all the other kitchen stuff also on the ring such as combi micro-wave oven, deep-fat fryer, kettle, washing machine, tumble-dryer. It adds up a bit doesn't it?

 

[plugwash]

I am having the same dilema.

Oven instructions say it should be capable of being isolated by means of a double pole switch.

6.5 kw Hob instructions say it should be on a 30 amp fuse, 230v x 30a =6.9 Kw.

Oven is 2.5 Kw, so ok to spur off ring main but it seems 2 separate double pole switches are needed by rights ????

thats one way

another way is to fit a 45A cooker control unit above worktop and then feed from there to a small CU http://www.tlc-direct.co.uk/Products/CMP2N.html in one of the cupboards

then just fit a 32A breaker for the hob and a 16A breaker for the oven.

 

[brumylad]

Been reading through a few old posts on here and reading my "electric wiring domestic" book by Brian Scadden.

It seems that it is acceptable to attach the hob and the oven to a single double pole switch and a single cooker outlet on a single 32 amp radial circuit. This is because of something called the diversity factor.

However there is no getting round the fact that although this way of doing things lies within the regs, if you were a very keen cook and the hob and oven were working at max. output, the 32 amp fuse would not be adequate.

 

[breezer]

This is because of something called the diversity factor.

at its most basic, diversity assumes that not everthing will be on at the same time.

even with an electric cooker the rings are operated by thermostats, so they will keep switching on and off

 

[Scoby_Beasley]

.....if you were a very keen cook and the hob and oven were working at max. output, the 32 amp fuse would not be adequate.

If you were a very keen cook you wouldnt have everything on max power as the "burnt saucepan" experience does not add to the tastebud tittilations.

 

[mick8332]

Hello
I have a similar problem . I have a low wattage oven to fit which according to the instructions must be fitted via a double pole fused switch. My problem is how to wire the cooker in to it neatly. I dont want to just run the wire into the wall and up some conduit, so would it be acceptable to wire a 13a plug socket in after the d/p switch and just plug the cooker into this , or does anyone have any better ideas.

 

[ban-all-sheds]

Yup -just have a socket - why bother with a switch? For isolation purposes you can either switch off at the socket, or pull the plug out, and the plugtop has the fuse....

 

[mick8332]

thanks