Seperate Cooker And Hob

[HIGH]

Hello All,
I am replacing my old combined cooker and hob for an up to date seperate cooker and electric hob. The cooker is rated at 1.8kw and the hob is rated at 5.8kw. At present i have a cooker control unit and a cooker connection unit with 6mm wire protected by a 32A fuse, I was going to connect the hob to this. I have a double socket on the ring main close by above the worktops, I was going to connect a FCU to this so this is on the ring and then spur a socket from the FCU down under the worktops and connect the oven to this socket. Am I correct in doing this as I am a stickler for doing things properly. I have seen occasions lately where the hob and oven are both connected into the connection unit? Awaiting your replies
Cheers

 

[ZenStalinist]

I would say your existing plan is fine... But why bother with a socket, when you could just use an FCU on its own, and have the oven supplied by that?

If you connect them both up to the cooker switch, you will need to upgrade to a 40 amp MCB.

I am not sure how you go about wiring two into one switch, however.

 

[BR]

I have seen occasions lately where the hob and oven are both connected into the connection unit? Awaiting your replies
Cheers

This is not strictly speaking correct, but not a huge issue.
The set-up you describe sounds fine, may I advise against having a new socket or switched fused connection unit behind the oven. In an adjoining press etc. might be more appropriate.

Personally I would spur of the cooker circuit to a switched FCU so as to have the one MCB protecting both appliances. This is certainly permitted in Ireland but perhaps somebody can advise on British regs.

 

[BR]

If you connect them both up to the cooker switch, you will need to upgrade the fuse or MCB to 40 or 45 amps.

I am not sure how you go about wiring two into one switch, but I would assume you use a couple of cooker connection plates wired radially:

There is no need to up the breaker to 40A. The absolute maxloading here is 33A, this is well within the overload parameters of the MCB an is not an issue. As for upgrading to 45A this should under no circumstances be done as it is exceeding the rating of the cable. Absolutely pointless anyway. Note my comments on wiring both into one switch.
The oven is designed for connection to a 13A socket outlet or FCU and will have a suitably rated flex for same.

 

[ZenStalinist]

I noticed that and edited the post accordingly.

I apologize for any brief few minutes anyone may have been influenced by it, and rushed off to wire their ovens like that without thinking to ask anyone else or wait for more replies

As for the 33 A thing, I would consider it bad to be overloading... even if it is within the design characteristics... It leaves no headroom at all for the power consumption that would occur when the supply voltage is towards the higher end of the tolerance limit.

 

[HIGH]

Thanks for the replies, the new oven in question has a flex but no plug so I was going to put an FCU above the worktops and then a flex outlet under the worktops the same as connecting a cooker hood. The reason I was putting an FCU above the worktop was so that the oven could be easily isolated, the same as a cooker control/connection unit and like you do for a washing machine or dishwasher.....any replies greatly appreciated.

 

[ZenStalinist]

Yeah, I'd say that's a good method.

 

[Scoby_Beasley]

[/quote]
Does anyone else have problems with these terminal types. i.e. instead of clamping the cable, the split threads spread and then the brass grub screw just spins ??

 

[dingbat]

Does anyone else have problems with these terminal types. i.e. instead of clamping the cable, the split threads spread and then the brass grub screw just spins ??

Yup. Not on cooker units, but certainly on lower rated junction boxes. I never use JB's with a rating below 20A for that very reason.

 

[HIGH]

Can anyone advise on the British Regs for spurring off of the cooker circuit as BR suggested in an earlier reply. If this is okay do you spur off of the cooker switch or from the cooker connection unit and i take it you use 6mm cable.......Cheers

 

[BR]

I would also point out that these are two seperate pieces of fixed equipment and as such should be on their own circuits.

The Hob should definitly be on a circuit of it's own due to it's rating. The oven can go onto a radial circuit or even a fused spur off the ring..own circuit is far better though.

Should you choose to run the two off the one circuit, I would strongly urge you to run the oven via a fused spur on the cooker circuit.

This is a quote from another topic. I'll take his word for it.
Two separate circuit's although ideal are not required here. You can, if you wish upgrade the breaker to a 40A. Yes, 6mmsq cable to feed FCU. As for where to spur from, wherever is easiest, CCU (switch) is probably best.

 

[HIGH]

Hello All,
Having read "The which book of lighting & wiring" By Mike Lawrence on the subject of wiring electric cookers he speaks about wiring a separate oven and hob using a cooker control unit for each or using just one to supply oven and hob, I know on previous threads there seems to be a lot of replies against the idea of using just one control unit and either spur off of the ring for the oven (depending on output) as i described in my first post or putting oven and hob on their own separate circuit any comments on this. Cheers

 

[securespark]

Does anyone else have problems with these terminal types. i.e. instead of clamping the cable, the split threads spread and then the brass grub screw just spins ??

Yup. Not on cooker units, but certainly on lower rated junction boxes. I never use JB's with a rating below 20A for that very reason.

I don't have a problem, but then I don't buy cheap c*appy jb's (not having a go!!) which usually are white, made in China and have nipples on the end of the screws (I shall leave myself open to whatever you lot want to chuck at me!!)

BG are good enough for me.