Current ratings for cable sizes

[John.Stitch]

Can someone point me in the right direction for the max current rating for cables.

I've done a search with limited success.

I am going to install a ceramic hob and built under oven.

I think the circuit has 6mm cable but will check.

Max draw of hob is 25A.
2x 1.7kW + 2x 1.2 KW= 5.8kW

5800/240=25A

Oven max draw is 12.29A

total is 37.29A

Diversity rule applies I believe.

10A plus 5A for socket plus 30% of remainder ( (37-10=27)*0.30=8.1A))

So 10+5+8.1=23A

Is that right?

 

[plugwash]

6mm should be ok on a 40A breaker provided thermal insulation is not involved

i would consider the cooker diversity guidelines as "if you need to" that is if installing from scratch you install a cuircuit that can take the full rating of the cooking equipment

finally its not absoloutely a requirement but with seperate cooking equipment some would prefer to put in a small CU (like the ones sold for garages) after the cooker control unit so each poart is protected by a suitable breaker. this has the added advantage of giign you an easy place to connect in feeds to things like cooker hoods if they aren't already availible from other cuircuits.

 

[John.Stitch]

Thanks, common sense in the main.
I think its a 30 or 32 A MCB in an RCD, but I can chenge it with the receipt.
BIt late to add wiring under the tiles, should have thought of it earlier.

 

[ban-all-sheds]

Can someone point me in the right direction for the max current rating for cables.

A Cable Selection Guide: here

A Cable Calculator: here

and also:

http://www.amazon.co.uk/exec/obidos/ASIN/0863413749

http://www.amazon.co.uk/exec/obidos/ASIN/0953788539

http://www.iee.org/Publish/Books/WireAssoc/index.cfm?book=WR 234

http://www.iee.org/Publish/Books/WireAssoc/index.cfm?book=WR 239

http://www.amazon.co.uk/exec/obidos/ASIN/0852962371[/quote]

 

[plugwash]

A Cable Selection Guide: here

it should be noted that that guide has a rather pesimistic interpretation of the regs

from what i have heared (i don't have the reference) a guidence note states that burried in a non insulating wall counts the same as clipped direct

 

[ban-all-sheds]

Well - better to err in that direction than the other.

Reference Method 1 is cables clipped direct or embedded in plaster. IMHO that means that anything deeper than immediately below the surface, or with capping, needs correction factors applied.