cable rating in kitchen

[Ian Atkinson]

Hi,

My kitchen is currently empty and I'm re-wiring it before I have a new one fitted. I have added in a few bits of extra cabling (spurs for cooker hood etc.) and replaced some sections with longer pieces in order to allow me to move sockets about. I've been using 2.5mm^2 cabling as this is what was recommended in the shop, I believe this this fairly standard.

All the sockets are on a ring and they are on a 32A MCB in the consumer unit. However, I have noticed on the packet for the cable that it says 'maximum load 27A' (the cable is made by Pirelli and is from B+Q).

Does this mean that I need to change the MCB for one of 27A or less? Or would that be the maximum load on a radial rather than a ring?

Thanks,

Ian.

[Andrew Gabriel]

It's the max radial load, although the actual maximum is really a complex function of ambient temperature, and how the cable is installed.

[David Hansen]

On 1 Oct 2006 05:00:10 -0700 someone who may be "Ian Atkinson" wrote this:-

No, as the sockets are on a ring there are two cables to carry the current.

It is a figure the shop or manufacturer have put on the cable to give people some sort of idea. However, the maximum load it can safely carry depends on things like how and where it is installed, the temperature of the surroundings and the characteristics of the protective device. A piece of cable embedded in insulation is allowed to carry less current than the same cable embedded in plaster.

[Christian McArdle]

No. To be suitable for a 32A ring circuit, the cable must be rated at 20A or above. 2.5mm complies, unless several derating factors apply, usually involving burying in insulation.

Christian.

[Ian Atkinson]

Thanks all for you help, I can plaster it in now without worrying about it!

Ian.