Radial to conservatory

[SW1970]

Hi, newbie here. Friend has asked for opinion on quote from another sparky. Single radial to conservatory replacement. Proposal is 6mm2 feed for 4 socket outlets and 6 lighting points back to CU. No mention of RCD or fused units in conservatory. Cable run 20m, floor area 25m2.

I think solution should be separate feeds of 2.5mm2 and 1.5mm2 back to RCD protected MCBs of 20A and 6A. Cable run is straightforward.

Can you guide on whether sparks approach is ok (in particular it all being on one circuit) and if mine is more appropriate?

Many thanks
SW.

 

[cliffed]

Guds mornin if theres no probs gettin bac 2 DB then all circuits taken 2 that.If major concern gettin 2 DB then personally i wud --- offa local circuits ie ring/lights cheers ta ra bab

 

[malcolmsanford]

Is there a reason he chose 6mm, was he worried about going into insulation which could in certain circumstances derate a cable current carrying capacity (Iz) by 50%.

I've not done a conservatory for several years now but have to admit the favourite method was to spur off a local ring final circuit in a FCU with a 13amp fuse to feed 3 or 4 sockets, and at any of the sockets take another FCU off with a 3amp fuse for the lights. It was mostly done like this to save cost really. Also by doing this you kept disruption to the main house to a minimum.

But every installation is different and perhaps they are going to use larger loads in this one, perhaps a portable AC unit. or some electric heaters, so you would have to judge what is the most cost effective really.

Certainly nothing wrong with your method, it will depend really on loads, disruption to the house etc

 

[Octopus]

Could be a struggle getting 2 x 6mm cores into each socket!

 

[Engineer54]

Yep!!, ....Seeing as the standard cable terminal connections on socket outlets and the like are suitable for a max 10mm2. So a bit of strand chopping required me thinks!!!...lol!!!