11.4kw cooker

[mcm]

been asked to connect up a cooker and found out it was 11.4kw 49amps, the supply cable only being 6mm 32amps.

using diversity what would this come to.

16 meters run
under floor boards and then in the wall.

 

[Geoffsd]

6mm and 32A MCB will be fine.

 

[davethsparky]

Assuming no other factors come in to play affecting cable selection.

Out of interest why not 4.0mm twin on a 32A? it's a standard circuit defined in the regs.

 

[Gasmeter65]

Fair comment on Kw. Forgot to say the run is approx 15 mtrs. I was thinking more along the lines of the Method of Installation ie; route of cable and being enclosed in plastic conduit/trunking B* 11.4kw max loading 49.5amps. 6mm in Method B* is 38amps. My main concern was running it behind the coving

 

[Gasmeter65]

aswell

 

[Geoffsd]

Assuming no other factors come in to play affecting cable selection.

But they do.

Out of interest why not 4.0mm twin on a 32A? it's a standard circuit defined in the regs.

Because it's in conduit.

 

[robsparky1975]

Who has ever undone a cooker switch to find a 10mm crunched into a standard deptch box,a cable calc will more often than not negate the upgrade to 10mm.

 

[Engineer54]

If the 6mm cable and 30/32A MCB is existing what the hell are you worrying about?? This 11.4KW cooker is well within the present circuits capabilities!!

 

[davethsparky]

But they do.


Because it's in conduit.

Apologies my post was not as clear as it should have been.

My question about the 4mm was more of a general why is 4mm not used for 32A cooker supplies when it is used for 32A socket radials?

 

[Geoffsd]

It's a remnant (if that's the right word) of 30A BS3036s when 4mm didn't comply because of the 0.725 derating factor.

The same for 3kW immersions and 2.5mm.

 

[davethsparky]

I had wondered if it was born out of tradition more than anything else.

 

[Engineer54]

I had wondered if it was born out of tradition more than anything else.

Been the same for 60+ years for domestic cooker supplies up to 15KW. Before metric cables it would have been 7/044 T&E. For immersions it was 7/036 T&E i believe...

 

[bigbud]

diversity = 21.87 Amps
fine as it is (6mm 32 amps)