32 amp circuit .. 2 ovens and induction hob

eggerb

I currently have an induction hob and a single oven on a 32 amp circuit. (Separately, I have a compact oven plugged into the kitchen sockets). I've never had any problems in eleven years.

I'm getting a new kitchen. Two 16 amp ovens and a 32 amp induction hob (max 7.2 kw) are planned. I haven't had the discussion with electrician yet. Can anybody shed some light on what he might/should propose? Will I need a separate circuit back to the board? I'm working on the basis that the existing circuit won't be able to take the proposed load.

Any advance insight much appreciated. Thanks.

eireyiddo

the cross diameter of the cable and the approx length of the cable run from your consumer unit is important. Also bare in mind, how often will ye have everything going at once? Maybe don't run the electric shower at same time!

eggerb

eireyiddo wrote: »

the cross diameter of the cable and the approx length of the cable run from your consumer unit is important. Also bare in mind, how often will ye have everything going at once? Maybe don't run the electric shower at same time!

Thanks for that. If the cable is over-spec'd does that mean I might be able to use the existing circuit and just replace the breaker on the board? The easiest option for the run back is probably from the ground floor to attic and back to the ground floor c. 20 metres. If that's problematic, a 10 metre run could be an option. No electric shower. Cheers.

eireyiddo

I've the same set up of double oven and hob running of 32a mcb 6mm cable, run of approx 10 meters. No issues. Christmas gives it it's best test. Wouldn't go near attic wit d cable. Shortest run best practice. Seek advice if ur unsure but I did the sums when I rewired two yrs ago. If it's a family home and your cables 6mm, d 32 amp breaker will be fine

eggerb

eireyiddo wrote: »

I've the same set up of double oven and hob running of 32a mcb 6mm cable, run of approx 10 meters. No issues. Christmas gives it it's best test. Wouldn't go near attic wit d cable. Shortest run best practice. Seek advice if ur unsure but I did the sums when I rewired two yrs ago. If it's a family home and your cables 6mm, d 32 amp breaker will be fine

Thanks eireyiddo. So, do you have two single ovens plus the induction hob? I'm not really sure about the cables. I'm sure the electrician will know what they are. If I have greater than the 6mm cables, might changing the 32A mcb be an option?

Here's some pics ...

eggerb

Pics

2011

eggerb wrote: »

I'm getting a new kitchen. Two 16 amp ovens and a 32 amp induction hob (max 7.2 kw) are planned. I haven't had the discussion with electrician yet. Can anybody shed some light on what he might/should propose? Will I need a separate circuit back to the board? I'm working on the basis that the existing circuit won't be able to take the proposed load.

I think that you may find that two circuits will be best, one for the hob and one for both ovens. However it is impossible to provide a definitive answer without knowing the rating of each appliance.

crossmolinalad

Never understood the way the English and Irish sparks works
I'm an electrician also and learned in Holland if a oven or a white goods say 220 v 16A your fuse must be 16 A and not 32 A
means that in our own country every thing white goods or ovens ect must have his own circuit breaker of 16 A
Induction hobs and other hobs a max fuse of 2x 16 A
Worked a while for Miele Germany they told me when I told them how it works here , we know that and they take ar big risk if something goes wrong in the electronics , the fuse of 32A wont go switch off and the machine will go on fire

Had a couple of years ago something similar in my rented house in the utility room
We always using the washing machine and the tumble drier together and had for a couple of days a weird smell in the house
Luckily for us the switch in the consumer unit tripped
what they had done both of the machines were plugged in in the same socked and was melted away aswel a part of the wiring
repaired it myself and have given them their own 16 A fuses

2011

crossmolinalad wrote: »

I'm an electrician also and learned in Holland if a oven or a white goods say 220 v 16A your fuse must be 16 A and not 32 A

In Ireland it s possible to protect "white goods" with a 16A fuse or MCB too. The load must draw no more than 16A and the cable must be sized appropriately.

eggerb

Thanks everybody for the input. I get the conversation about protecting each appliance. From a consumers perspective, being able to plug the appliance into a 16 amp socket, if such a thing exists, would make things a lot easier too.

Below is the rating of the appliances. So, by the looks of it, I probably need a new 32 amp run back to the board protected by another 32 mcb?

Any thoughts anybody (?) on what the existing wire might be based on the dimensions of the external pvc sheathing : 13.5mm x 8mm

Oven 1
Electrical connection rating (W) : 3600
Current (A) : 16
Voltage (V) : 220-240
Frequency (Hz) : 50; 60

Oven 2
Electrical connection rating (W) : 3600
Current (A) : 16
Voltage (V) : 220-240
Frequency (Hz) : 50; 60


Induction Hob
Electrical connection rating (W) : 7200
Voltage (V) : 220-240
Frequency (Hz) : 50; 60

eireyiddo

The size of the cable inside is printed along the external sheathing. If you have an electrician lined up for this job let him earn his money and run whatever cables and fit whatever mcb's are reqd. With regard to the issue with plugtop melting due to constant use of an appliance, that could not happen in this situation it the cables are the terminated correctly.
At a guess, you've got 6mm twin and earth there in the calipers and with a 32a. There won't b any issues running everything off this.

Risteard81

crossmolinalad wrote: »

Worked a while for Miele Germany they told me when I told them how it works here , we know that and they take ar big risk if something goes wrong in the electronics , the fuse of 32A wont go switch off and  the machine will go on fire

Well I can't entirely agree with them. We work on the principle that the protective device must protect the cable (from overload where applicable (and this can otherwise be omitted) and fault current (short circuit or earth fault). If their appliance needs protection for the internal components then that is their duty as the manufacturer to provide it - it is not the job of the National Wiring Rules.

Stoner

Risteard81 wrote:

Well I can't entirely agree with them. We work on the principle that the protective device must protect the cable (from overload where applicable (and this can otherwise be omitted) and fault current (short circuit or earth fault). If their appliance needs protection for the internal components then that is their duty as the manufacturer to provide it - it is not the job of the National Wiring Rules.

That's how I see it too.

There's a huge amount of commercial lighting jobs completed with 25 amp busbar trunking protected by 25Amp MCBs.

These often use 1.5.sq.mm cable in the ceiling zone via unfused tapoffs to feed lights. The length run being under 3M busbar to fitting

The busbar suppliers Schneider and the like will provide a risk analysis saying that this is ok as the cable is at high level so reduced risk for touch voltage , the run is so short that the 25 Amp MCB will see a short cct fault in time.


At the end of the line there's a light fitting that should be internally fused, but the route to it is protected.