Ask a Tradesman
Will 6mm cable be ok. Double oven and electric gridle with cable run of 20meters, on 32 amp braker. Oven make smeg A4BL-8
To be able to do a full cable design calculation, you need to know max Kw rating of the cooker and the particular installation method to be used (i.e. whether the cable will be run on the surface of the wall in conduit or mini-trunking or buried below the finished plaster depth). If the cable is to be run through loft/wall insulation then it will be derated by up to 50%.
As a rough guide 6mm is good for 40 - 42amps. So provided the oven is below 9kw, you will be ok for the current carrying capacity of 6mm on a 20m run if its a standard under the foor and cable chased into the wall installation. You would get a volt drop of about 5.7 volts on 20m at a full load current of 40amps (9.2kw).
A BSEN60898 type B 40amp MCb could be used instead of a 32amp.
Please note that all electrical work in the kitchen is subject to part P of the building regulations, so you will need to notify your local building control to get consent to carry out the work and pay their fee. - google part P of the building regulations for more information. - (breaching part P of the building regulations can result in a fine of up to £5000)
Hop this helps.
Answered 24th Oct 2012