Wire spec for cooker, full MCB to outlet details attached

[visordown]

Hi all,

Just joined up and was hoping an electrician could confirm if the following is correct.

We have been advised to use 6mm twin and earth for the installation of the following (cooker to outlet), is this correct?

Belling 668 double oven maximum load 10450W
The NICEIC Domestic Electrical Installatiopn Certificate details the the following spec for the cooker wiring already installed
Type of wiring =A
No of points served =1
Live: 6mm2
Earth: 4mm2

60898MCB
Rating 40A
Capacity 10kA
RCD operating current 30mA

THe cooker manual recommends the above cable as does a local spark, just want to confirm this will all be ok.
Should a heat resistant cable be used?


Thanks in advance for any help you can offer

 

[333rocky333]

Do they make 6mm with a 4mm earth?

 

[visordown]

pass, only going by the cert, rest of the circuits are 1.5/1 or 2.5/1.5, the cooker circuit definately shows 6/4 though

 

[SparkyNinja]

A maximum load of 10450w would exceed the 40A MCB, and I doubt the CPC is 4.0mm




You from VD?

 

[visordown]

hi, no used to be but on 4 wheels now.

I am confused then, will it need a 45A MCB put in, will the 6mm twin and earth then be ok for the outlet to cooker. THe NICEIC cert must be misprinted re the cpc then

 

[333rocky333]

Usually 6mm/2.5mm
Maybe a seperate 4mm earth has been run with it to supplementary bond it. for some reason.

 

[SparkyNinja]

I am confused then, will it need a 45A RCD put in. THe NICEIC cert must be misprinted re the cpc then

It would be the Over-current protection device (MCB)

How long ago was the Cert issued? Is it all nicely typed up?

 

[visordown]

hi, thanks realised and edited my post but it re-posted it!

it was issued July this year (new build), yes it is all typed up

I am at a loss why the developer would put a 40A MCB in if 45A required, or is this cooker at the higher end of maximum loads?

 

[VanSolo]

Do the NICEIC domestic certs have a column for installation reference method?

 

[BS3036]

Why tease the guy? There is no problem running a 45A oven on a 40A MCB. You know, diversity?

 

[visordown]

yes, the installation reference method is 100.

Thanks, so i am ok using 6mm twin and earth and the 40A MCB?

You lot have succeeded i will just get a spark in at this rate!!! lol! Only want to get some food cooked!

 

[VanSolo]

I was genuinely interested whether that column was on the form as you did not mention it. Thanks.

 

[ColJack]

Why tease the guy? There is no problem running a 45A oven on a 40A MCB. You know, diversity?

I keep saying it but no one listens to me..

Diversity is for the TOTAL DEMAND of an installation.. based on that not everything in the entire installation is going to be on at maximum capacity all the time..
it is NOT for determining the cable or CPD size of a SINGLE CIRCUIT..
if it says 45A then you need to fit 45A cable and 45A breakers etc MINIMUM..
it may very well never use the whole 45A but it can do..

after all, with diversity applied I can get a 9.5KW cooker on a 20A breaker fed with 1.5mm² T+E ( REF method C )... but that's just not right..

EDIT: REF method added for the sticklers..

 

[SparkyNinja]

^^^^^^^^^^^^^^^^^
I agree with what he says

 

[ColJack]

yes, the installation reference method is 100.

Thanks, so i am ok using 6mm twin and earth and the 40A MCB?

You lot have succeeded i will just get a spark in at this rate!!! lol! Only want to get some food cooked!

ref method 100 you should have 10mm² installed in the wall.. as 6mm² is only rated at 34A for that method..