Join Radials at Consumer Unit?

[TomUk]

Hi, just swapping out an old rewirable type fuse box for a Dual RCB CCU. Bit of a nightmare as most of the incomers dont reach. Also its an old house which has had quite a few extra Radials, and lighting circuits added as new circuits.

My question is; rather than have 3 seperate Radials, 4 seperate lighting and 2 rings can i join a few of them in the MCB at the CCU. Ie, is it acceptable to run two radials from a 16amp MCB and likewise 2 lighting circuits from one 6a mcb. Actually one radial already had a spur straight out of the MCB to a socket. Obviosuly im not going to run 2 rings from one 32a! I cant see its any differnt to having one lighting/power circuit with many points.

Thanks guys

 

[Sherbertlion]

Consider safe isolation of individual circuits. What would you think was going on if you went to a job to fault find and found two 2.5 in the same breaker and then started testing e.t.c?

A spur from the board is okay but not anything more (please don't start the "what is a spur" debate again).

If you're changing the board why not just have the individual circuits. If they don't quite reach then extend the cables I reckon.

 

[industryspark]

Whilst i would recommend that you sort the circuits out properlly in a better fashion i would also say that there is nothing wrong with what you propose.

2 radials from a 16A mcb is fine, its not really classified as 2 circuits, it will be one 'branch' circuit. Make sure that the loading of the circuit will be okay though for the circumstances, 16A isnt a massive amount.

As for identifying then yes this could be an issue but you can resolve this by labbelling correctly and adequatlly. If i found two 2.5mm in a 16A mcb i would assume radial not ring so cant see the issue with that. As for safe isolation of circuits, if you dont prove dead after you think you have switched off then your not doing yourself any favours to start with.

 

[Sherbertlion]

Yep, fair enough. I don't assume anything anymore ... far too dangerous!

The other day found a ring with a third cable coming into it at the board. Initial thought that it was a spur... no. Then thought maybe someone had put it in the wrong breaker as next to it was another 30A 3036 with 1 x 2.5mm i it...no, that turned out to be a radial!

The electrician who worked on this property some years ago had extended the ring by adding another cable into the existing ring and breaking into it all over the place... blah blah. Right mess. Re-wired most of it.

 

[TomUk]

thanks for replies. Great forum that you can get 2 good replies at 10:30 within about 10 minutes!

Actually it was the same here, their was a ring off a 32a with a radial in the same breaker. Their was also 2 radials in a 16a breaker. I' am slowly rewiring it but it could be a months work! The house house was wired 40 years ago by a DIY guy and added to since then...

 

[ban-all-sheds]

My question is; rather than have 3 seperate Radials, 4 seperate lighting and 2 rings can i join a few of them in the MCB at the CCU.

Get a bigger CU.

 

[TomUk]

Get a bigger CU.[/quote]

Fair enough, but to be honest im not sure i like 6 or 7 power circuits and 4/5 lighting circuits in a one story house. It seems a bit OTT (each room having its own circuit breaker).

 

[TomUk]

Get a bigger CU.

Fair enough, but to be honest im not sure i like 6 or 7 power circuits and 4/5 lighting circuits in a one story house. It seems a bit OTT (each room having its own circuit breaker). But i'll take your advice, their are actually spare ways on the board.