Ring or Radial

[Pete]

With all the talk about radial circuits I was just trying remember from previous discussions that it was difficult to connect two 4mm cables in the back of a socket? 

If I use deep back boxes as suggested then is it the way forward. I have a lot of 4mm cable and would like to use this for the sockets but do it as a radial circuit instead of a ring. TIA 

[MikeSharp01]

You can move a lot of juice on 4mm cable it is more than you need as 2.5mm is all you should need for a noral ring. If you have loads of 4mm why not trade it in for even more 2.5mm.

 

 

[Onoff]

if it's old colours you could retire!

[Jeremy Harris]

You can normally run radial finals on 2.5mm² up to 20 A (subject to any derating that may need to be applied if the cables are running in insulation).  The limit (off the top of my head - I don't have the regs with me) is, I think, 50m² floor area per radial final, so most houses would probably need around three or four 2.5mm² radials, protected with 20 A (not 30 A or 32 A) MCBs or RCBOs.

 

My 24m² floor area workshop is pretty well flooded with outlets (currently there are 18 double gang sockets in there, so 36 outlets in total........), run on two radials, wired with 2.5mm² and each protected with a 20 A MCB. 

 

Edited August 30, 2017 by JSHarris