2.8kw Electric oven and 5.8kw electric hob install

[DaveEJ20]

I am looking to run a 5.8KW hob and 2.8KW oven on a 40amp circuit, over about 6 metres, with the cable in plastic conduit recessed into a concrete floor.

Will voltage drop and the way the cable is covered affect its ability ?

I work it out at 37amp (@ 230V)

does this sound OK?

Kind regards

Dave


Reply:

"given your oven is less than 3kw, install a socket for it, so its protected by a 13 amp fuse. This can be on the cooker circuit, so it also goes off when you turn off the cooker isolator switch above the 'top.

Make it a 32 amp circuit, with at least 6mm cable

Steve"

 

[DaveEJ20]

Thanks for the reply,

So are you saying i only need a 32amp circuit to run the hob AND the oven with the oven on a 13amp socket?

regards

Dave

 

[Steve]

Yes. Using discrimination the circuit can handle that load. Its unlikely the elements on the oven and hob will all be running at once, as they cycle on and off on thermostats.

 

[DaveEJ20]

Ok thats good news then as it currently has a 32amp circuit in place, I thought i would have to up it to 40 when working it out for the new oven!

So I can use one of these DP switches above the work top:

http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A431905&ts=43423&id=55609

with two outputs, one to the connection box of the hob, and one to a 13amp socket, both below the worktop?

thanks for your help.

Dave

 

[Steve]

Yes that switch is right, use this to feed a socket, and one of these:
http://www.screwfix.com/app/sfd/cat/pro.jsp?cId=A431906&ts=50873&id=16686
This is a cooker outlet plate. This is where you connect the fixed circuit wiring from the switch, to the cable to the hob.

I know its a bit more expensive, but use this switch, MK is a better brand.

 

[Steve]

By the way you cannot bury twin and earth in plastic conduit, unless its 5cm below the surface.

You must afford the cable an earthed metal sheath, by using an armoured cable, or earthed metal conduit.

Such armoured cables include:
Steel wire armoured
Split concentric
Mineral Insulated Copper Clad



Alternatively run the cable elsewhere.

 

[DaveEJ20]

great thanks for the info, i think the easiest run will be across the concrete floor, (its a right pain having concrete floors).

Where can i get some earthed conduit?

cheers again for the info.

cheers

Dave

 

[DaveEJ20]

Ah Ha!

http://www.tlc-direct.co.uk/Products/SW6slash2.html

this should be ok then?

Dave

 

[Steve]

Ah Ha!

http://www.tlc-direct.co.uk/Products/SW6slash2.html

this should be ok then?

Dave

Perfect, however get 3 core, and dont forget the glands and the right boxes to terminate it.

split concentric is much easier to do, it doesnt need glands or boxes, but harder to get hold of.

 

[DaveEJ20]

Didn't realise i selected 2 core, i see the 3 core now, and these glands:

http://www.tlc-direct.co.uk/Products/TLB20.html

do they allow the SWA cable to be connected to ordinary 6mm cable?

Cheers

Dave

 

[DaveEJ20]

Useful link:

http://www.ultimatehandyman.co.uk/armoured1.htm

Cheers

Dave

 

[Steve3948]

Better to put a 25mm Conduit in the floor and earthed.
At least you can then pull the cable out should it get damaged.