oven supplies 4mm or 6mm???

[A032701]

I am often installing two 3.5kw ovens in one kitchen which amounts to 30amps.
I cant see that there are any problems with supplying them both with a single 4mm on 32mcb, (installation method c)
i have normally supplied it in 6mm but just wondering really. is it just bad practice, in case they uprate the ovens?

 

[Octopus]

Whats the installation method of the 4mm cable?

 

[A032701]

c.. i have edited the op.

 

[Charlie_]

If they update the ovens then they need to uprate the mcb too..
If your calcs are all ok then stick to 4mm

Must be short runs though, with no insulation, etc?

 

[Pete999]

I am often installing two 3.5kw ovens in one kitchen which amounts to 30amps.
I cant see that there are any problems with supplying them both with a single 4mm on 32mcb, (installation method c)
i have normally supplied it in 6mm but just wondering really. is it just bad practice, in case they uprate the ovens?

Will depend on what the cable sizing calculations turn up, doesn't it???????????

 

[Andy78]

I always use 4mm where I can.

 

[Dustydazzler]

Much prefer 4mm for terminating in tight spaces , single boxes etc...so much neater and easier to fold back in.

 

[Pete999]

Much prefer 4mm for terminating in tight spaces , single boxes etc...so much neater and easier to fold back in.

Agree but if 4mm doesn't meet VD etc requirements, installation methods, it's irrelevant.

 

[Rpa07]

So bizarre when you run a 6mm then from the cooker outlet plate you use their cable that is a 1.5 or 2.5mm flex - I sometimes shake my fist at technological improvements!
I’m deffo one for 4mm runs if cable length and load don’t scupper the idea.
More people are having duel fuel so it’s a piddly oven that will never get over 9 amps with the wind behind it!

 

[l4urence]

Good thread, I've had this discussion before. Simply put do the calcs on the cable / installation method and fit the right cable - if that's 4mm then so be it. However, a look at the manufacturers data sheet will advise the size they recommend (this has little regard to the installation method of course)! I do wonder how many ovens were fitted (with installation calcs) and then loft / void was filled with insulation maybe years later negating the installation!

 

[l4urence]

Remember - if the oven is delivered and fitted by the supplier, they will simply not install it if they deem the cable the wrong size and they are told the 'minimum' size it should be. Your calcs may be correct but the oven / hob doesn't get fitted and you get called back - not good.

 

[Midwest]

I'd run 6mm.

When the electric ovens are replaced with new fangled Fusion energy ovens, the cooker circuit could be used as an electric charger for one of these

You should always plan for contingencies

 

[l4urence]

I'd run 6mm.

You should always plan for contingencies

I would certainly agree with this.

 

[A032701]

thanks for that everyone
might as well just run them in 6mm's to be future proof

 

[Rpa07]

I think that, in this instance, future proofing seems to be a smaller CSA cable - I’m kidding but does seem to be the case!

 

[A032701]

I think that, in this instance, future proofing seems to be a smaller CSA cable - I’m kidding but does seem to be the case!

Yeah but better to have too large csa than re running because its too small.

 

[l4urence]

I think that, in this instance, future proofing seems to be a smaller CSA cable - I’m kidding but does seem to be the case!

Interesting! Reading recently that as we move to more energy efficiency the csa will go UP so the cables run cooler for such loads. I think we'll see the regs pushing more for this in the 19th... 20th? I wonder how much influence the cable manufacturers have on the IET?

 

[telectrix]

use 1.5mm strung in free air. dry the dishcloths on it. 2 uses for the price of 1.

 

[MG201]

I have seen many a kitchen fitter using 2.5mm cable and spur off the kitchen ring . This is used for a cooker and hob, absolutely shocking and when I ask I get the attitude , just wait till Xmas when they have the oven on and all the rings maybe even the grill , if I'm right they won't be cooking any Xmas dinner as that cable will be melting ( am I right )

 

[Deleted member 26818]

I am often installing two 3.5kw ovens in one kitchen which amounts to 30amps.
I cant see that there are any problems with supplying them both with a single 4mm on 32mcb, (installation method c)
i have normally supplied it in 6mm but just wondering really. is it just bad practice, in case they uprate the ovens?

Though 4mm2 can be acceptable, I would prefer to use 6mm2.
As you say they may uprate the ovens.
Then again, I have no idea in the difference in price between 4mm2 and 6mm2.