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Hi, I am a first time DIY poster - hoping to navigate the tricky line between getting a bit of a steer in the right direction and not requesting step by step instruction.

I am hoping to DIY the electrics on my extension, and in advance of the project I am trying to map the order of outlets on the existing ring mains. I am aware of the area of work R1 + R2 / 4 etc etc testing for faults and reckon this is DIYable (once a professional has repaced my old fuses with a CU, and added a big off switch just past the meter). My question is can anyone point me in the right direction for establishing in which order the outlets on the ring main run. I can think of a painstaking route of disconnecting two at a time so that anything else dead is then known to be inbetween the two, and if nothing else is dead then they must be adjacent, always keeping a look out for extra wiring suggesting a spur - am I on the right lines or is there a better method, perhaps with a multi-meter?

Incidently I am undertaking 20 days City and Guilds training in May (yes, am aware of the limitations and that this might make me an enhanced DIYer, but certainly not a sparks). I am super cautious on all isolaton matters - hence new isolation switch for whole house.

Sincere thanks to all the eperienced posters who are willing to share their expertise.
 
If you are planning on doing your extension wiring, best you discuss this with your local building control if you want them to issue a completion certificate .....
 
Duplicate thread from earlier this week?
 
Yes, but was on wrong forum earlier today, so have made my farewells there and moved this to DIY forum
 
Yes, but was on wrong forum earlier today, so have made my farewells there and moved this to DIY forum

You won't get step by step guides in here either
 
No, and that is a fair enough rule. I did not think that is what I am asking for - (I was hoping for a couple of sentences to point in the right direction)... but apologies if that is clearly what I am doing and I am sure I will get the hang of what is acceptable by keeping quiet and reading others' posts for a bit.
 
Well you are the King of your castle. Nothing wrong with wanting to find out out what lurks beneath the surface.

I would invest in a bosch wall scanner. Very handy in locating live cables in the wall. Lift floors if necessary. With a bit of common sense it's not that difficult to find out.
 
@OP.a bit late, but.... you could ( if competent) , after isolation take readings R1+R2 from each socket. as you move from CU round rfc, readings will increase.
 
Thanks for the replies - penny has dropped. Christ that was simple and am feeling a bit foolish now! I was focussed on R1 + R2 remaining constant as proof of connections, and forgetting the fact that one will increase and the other decrease, as you work your way around - this is what comes of reading, but not yet physically doing it. Will crack on now - thanks again.
 
Hi, I am a first time DIY poster - hoping to navigate the tricky line between getting a bit of a steer in the right direction and not requesting step by step instruction.

I am hoping to DIY the electrics on my extension, and in advance of the project I am trying to map the order of outlets on the existing ring mains. I am aware of the area of work R1 + R2 / 4 etc etc testing for faults and reckon this is DIYable (once a professional has repaced my old fuses with a CU, and added a big off switch just past the meter). My question is can anyone point me in the right direction for establishing in which order the outlets on the ring main run. I can think of a painstaking route of disconnecting two at a time so that anything else dead is then known to be inbetween the two, and if nothing else is dead then they must be adjacent, always keeping a look out for extra wiring suggesting a spur - am I on the right lines or is there a better method, perhaps with a multi-meter?

Incidently I am undertaking 20 days City and Guilds training in May (yes, am aware of the limitations and that this might make me an enhanced DIYer, but certainly not a sparks). I am super cautious on all isolaton matters - hence new isolation switch for whole house.

Sincere thanks to all the eperienced posters who are willing to share their expertise.

Go way amd get an electrician
 
@OP.a bit late, but.... you could ( if competent) , after isolation take readings R1+R2 from each socket. as you move from CU round rfc, readings will increase.

I thought it was a ring circuit!
R1+R2 should be the same wherever its is measured on the ring, not increase or decrease!
 
As a rfc the readings should remain constant. However if you link out l&e on one of the legs and make it into a radial, the readings will adjust according to circuit length
 
Of course but didn't think we were supposed to give step by step instructions!
The OP doesn't really say why he needs to know?
 
OP here - What I want to do is DIY electrics on my house extension, this will be some connecting into existing ring circuits, plus a couple of new ones. I am undertaking some basic training in a few weeks time, but I want to try and get ahead with my own project, so I want to map the exiting installation so I can see which circuits I can join into, how and where, whilst maintaining the integrity of the existing circuit. I am undertaking some training shortly, 20 days C&G - will not make me a sparks by any stretch, but will hopefully expand my DIY range and keep me safe.

Chris Gray - thanks for the tip to make it into a radial - again all too obvious once you know - I hope that is where I would have ended up anyway - but it might have taken a while.

DefyG - thanks for the alert - I never took Telectrix post to mean that R1 + R2 should deviate on a ring main, because I was certain myself that it shouldn't, but I rated it highly because it set me onto the thinking which I outline below, even though I then wrote wrongly about R1 going up as R2 went down. What I was thinking is that when step 3 testing at outlets, there are two loops of resistance from live terminal to earth terminal as per the need to divide by 4 rather than by 2. So resistance of one loop would increase as you progress from outlet to outlet whilst the other decreases, as per the increasing / decreasing proportion respectively of the 2 loops that is formed by the earth cables different cross section. So, I was trying to figure out how to disaggregate the resistance contribution of the two loops at each outlet which is overly complex compared to the simple (and no doubt correct) method suggested by Chris Gray.

So, perhaps I was too absorbed with the Stage testing, and needed to take a step back to something more obvious. However I think the Step 2 / Step 3 testing should be useful to me for identifying a spur, if there are any, rather than simply a position on the ring.

Kind regards, and thanks again to all.
 

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