Splitting a ring into 2 radials

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bhamoggy

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Im proposing to split a downstairs ring into two radials. Basically, a door has been put in the rear wall and the cable running along the skirts will be interfered with. Concrete floor makes going down a non starter and I don't really want to run new cable up an down the walls.

My proposition is to remove the section and turn them into two radials and putting the legs into individual 20A breakers.

Problem is, there may not be a pace for another breaker in the c/u.

A friend reckons I may be able to put both feeds into one 16A breaker if there is a problem.

I'm not sure, hence I thought someone e on here will know

 
So why not place a NEW socket either side of the door then from each of these sockets go vertically up and then across the top of the door within 150mm of the ceiling. Then you still have your ring and the cabling is within the safe zones. Just a thought!

 
So why not place a NEW socket either side of the door then from each of these sockets go vertically up and then across the top of the door within 150mm of the ceiling. Then you still have your ring and the cabling is within the safe zones. Just a thought!
Steel lintel across top of the door frame and he dont really want me chasing the wall out, the socket to the right of the door is on a plaster boarded wall and he don't want the wallpaper damaged so splitting is only real option

 
Was going to suggest butting a socket either side of the door with architrave trunking. BUT the bit over the top of the door wouldn't be in an obvious zone...........

 
No problem with splitting the ring, no problem with putting both sides into one OCPD except for possible overload and therefor tripping. Why do you suggest using 2 x 20a MCB's if separate or 1 x16a if together? Can all go on 1 x 20a. As I say though you will have to give some thought as to what possible loading there will be. It's downstairs, does that mean it also covers the kitchen?

 
In the c/u there is upstairs ring and downstairs ring but there is also an mcb with "sockets" written on it. I'm hoping that the kitchen may be on that circuit but I've not checked to see what circuits are doing what. Quickly looked at the job yesterday and going to do it this Thursday .

If the kitchen is on the downstairs ring, is it inadvisable to put both radials into one mcb even allowing for diversity ?

 
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In the c/u there is upstairs ring and downstairs ring but there is also an mcb with "sockets" written on it. I'm hoping that the kitchen may be on that circuit but I've not checked to see what circuits are doing what. Quickly looked at the job yesterday and going to do it this Thursday .If the kitchen is on the downstairs ring, is it inadvisable to put both radials into one mcb even allowing for diversity ?
Without seeing what is in the kitchen I would still say yes, inadvisable. Nuisance tripping is a nuisance for you too. It's you they'll be ringing to sort out their problems.

 
you could always put an adjacent cu in ????

6mm from existing mcb to a 2 way board with 2x20amp mcbs

upgrade the original mcb to a 40 amp...........job done

 
In the c/u there is upstairs ring and downstairs ring but there is also an mcb with "sockets" written on it. I'm hoping that the kitchen may be on that circuit but I've not checked to see what circuits are doing what. Quickly looked at the job yesterday and going to do it this Thursday .If the kitchen is on the downstairs ring, is it inadvisable to put both radials into one mcb even allowing for diversity ?
I would suggests you do not start any work until you have established that the existing installation is satisfactory for the amended circuit arrangements. e.g. balancing of loads around circuits, earthing arrangements etc. I fail to see how you can even consider breaking or splitting any circuit without first identifying exactly what that circuit feeds and what size cables are on that circuit. There is a regulation about it not doing any amendments temporary or permanent.

Doc H.

 
Other considerations aside (see Docs post), if it's a Hager board, you could put your 2 radials on a 25A breaker (or put in a small 2 module enclosure and make each radial 25A fed from a 40A in the original way). Many ways to skin a cat and all that.................

 
I would suggests you do not start any work until you have established that the existing installation is satisfactory for the amended circuit arrangements. e.g. balancing of loads around circuits, earthing arrangements etc. I fail to see how you can even consider breaking or splitting any circuit without first identifying exactly what that circuit feeds and what size cables are on that circuit. There is a regulation about it not doing any amendments temporary or permanent.Doc H.
How does the earthing arrangement affect it? It's TNS by the way. I just done the 2382-12 on the BGB last week and didn't see the regulation you mention.

P.s. I've been working at this for 6 months only so need all the help possible.

Been to college and got all the qualifications but they don't teach you how to get past day to day problems

 
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so, let me think about this,

this guy is cutting a big-ish hole in his wall to put a new door in, and doesnt want you cutting a few small tracks in his walls cause it will make a mess?!

the thing puzzling me is this, if you havent actually looked at this job much what makes you think putting a door in will affect your ring?

very very seldom have I come across sockets that are wired horizontally, have you actually confirmed the cable routes?

the socket you are talking about may well be a spur.

 
The door is already in, it's just under the door left to brick up and that's where the able is running. Walls have already been made good. The return wall is plasterboard.

One wall brick 90 degs to theplasterboarded wall

---------- Post Auto-Merged at 19:42 ---------- Previous post was made at 19:38 ----------

Unlikely to be a spur cause the socket left to the door has conduit running along the wall to the right of the door and buried into the wall fixed just above the skirting board

 
I love the way that everyone else's problems become ours when they rush ahead into things and leave it to us to sort it out without and damage to the building fabric or decoration..

Just like, could you add some sockets, but we've just laid laminate flooring and decorated the walls???

 
I love the way that everyone else's problems become ours when they rush ahead into things and leave it to us to sort it out without and damage to the building fabric or decoration..Just like, could you add some sockets, but we've just laid laminate flooring and decorated the walls???
Lol

And there is laminate on the concrete floor

 
What's the other side of the wall with the door in? Could you go through the wall from the socket one side of the door frame into another socket then up over the door frame that side, back down to a second new socket then through the wall to connect to the other side of the ring? Hope that makes sense!

 
Sometime the problem with splitting the ring into 2 radials is that you end up with 1 very short radial and 1 rather long 1. The short radial isn't a problem but a long radial with a lot of sockets can cause many problems like over loading or high zs reading, you normally get away with it but worth checking before you choose which size Mcb to fit

 
What's the other side of the wall with the door in? Could you go through the wall from the socket one side of the door frame into another socket then up over the door frame that side, back down to a second new socket then through the wall to connect to the other side of the ring? Hope that makes sense!
Think I get you but it's a rear wall, the door now sited leads into back garden

 
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