Cooker and Hob Coming off same 40a circuit

[sl1210]

Hi guys,

Went to fit a new oven for a friend of mine where the old one was connected to a cooker connection unit which also supplied to induction electric hob. This is fed by a cooker switch in 6mm on a 40a mcb.

Now the oven is supplied with a kettle lead and says its 1.5mm on the cable, i don't feel comfortable leaving this on a 40a circuit as the cable surely isn't capable of taking 40amps in fault conditions. Now normally i would have just wired the cooker in 6mm t+e but as its a kettle connection this isn't an option.

Even then theres a chance the breaker would overload anyway with everything on as the hob is 32a on full load and the new oven is 13a. Although i don't think this was a problem before.

I never had any materials on me to finish the job on saturday, but all i can think to do when i go back is come of the connection unit with a 13a spur to supply the oven.

Is this the best option??

Cheers

 

[sl1210]

I have temporarily connected the oven to a connection unit supplied by a 13a switch spur, which was supplying the washing machine. But advised him that using the washing machine and oven at the same time will blow the cartridge fuse. So use one or the other ;0))

 

[GLENNSPARK]

Zs will verefy disconnection times....
the cable that feeds the cooker will be adequate for the job (it came with it)....so..
the cable is enough for the current demand....dont confuse demand with fault (disconnection times)...

 

[sl1210]

yes but wasn't that cable intended to be protected by a 13a plug top or spur???

 

[ses]

But the oven is a fixed load

 

[GLENNSPARK]

yes but wasn't that cable intended to be protected by a 13a plug top or spur???

yes...sorry...
drop your MCB down to 16A...

 

[jaydee81]

check manufacturers instructions have always done as you say and come off cooker outlet with fused spur of single socket

 

[GLENNSPARK]

is the hob still runnin of ov this?..
if so then keep MCB at 40A....use an FCU for the cooker spurred of ov the hob (existing supply)...

 

[sl1210]

yes the hob is still running so the 40a mcb will have to stay. could i come off the cooker outlet with 2.5mm twin and earth to the spur for simplicity. As the load would be protected by a 13a fuse???

 

[SYKRAPS]

I would be spurring off in 6mm as 2.5mm is not suitable for a 40 amp mcb

 

[sl1210]

yeah i thought so. i'm just being lazy trying to fit all the cables in. haha

 

[GLENNSPARK]

I would be spurring off in 6mm as 2.5mm is not suitable for a 40 amp mcb

no...its max demand will be dictated by the fuse`s max let through....13A in this case....
a 1.5/1.0 would do....but use a 2.5/1.5 to feed the FCU...

 

[sl1210]

ok great that will make life easier. yes thats what i was thinking, that 2.5mm cable would never draw more than 13amps

 

[MDJ]

agree with glen, I would just add a 2.5 to the connection plate and connect to a spur as well, or a single socket if the oven is under 3kw

 

[SYKRAPS]

So why can't we spur from a 32a ring using 1.5 t+e unless it is fused down to 13a?

 

[GLENNSPARK]

agree with glen, I would just add a 2.5 to the connection plate and connect to a spur as well, or a single socket if the oven is under 3kw

the `3KW` you refer to is for cookers fed from a ring final.....
its 2KW by the way

APP 15 fig 15A (iii)....

 

[i=p/u]

Glens parks I see you still don't have a clue

 

[sl1210]

can't come off the ring as the sockets are high level behind a splashback. all the sockets low level are for the appliances and fed from fcu's in the cupboard

 

[GLENNSPARK]

you don`t need to....you`v got a supply there already thats adequate......use that....

 

[sl1210]

yeah i am going to use the connection unit to spur off. just explaining to sykraps why i can't come of the ring