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Paul_K

Hi all,

I'm still learning this stuff so go easy!

I've just carried out a ring final circuit test. Having identified both legs of the ring I began testing between both ends of the line conductor, which has given me an infinite reading on the meter. I also got the same result on the cpc. When testing the neutral I get 0.56 ohm..

The answer to me suggests I have an open cpc and neutral on the circuit. Am I on the right path here, or have I missed something?

Thanks in advance!

The tester is a Fluke 1653B
 
open circuit on L and cpc. rN is 0.56 ohms so you would expect r1 to be the same. if it's T/E cable, 2.5mm, then expect the cpc ( r2 ) to read about 0.9 ohms.
 
Thanks Telectrix, it is T+E, just needed to confirm that as I'm not well experienced in the testing yet, even though it appears obvious! :-/
 
Hi ifindoubtdont,

Yep, the ring is on the one breaker (32amp).. Both lines removed from the same breaker, and traced right back to the mechanical insulation where their neutrals and cps were confirmed, which were also together in their respective slots in the board! :-/
 
so it looks like you have bad/broken connections in a socket, JB, or a damaged cable.
 
not necessarily. look at the socket circuit as a whole. estimate an approx. mid point. then use a wander lead to find which leg has the fault/s. then split that leg and repeat untill you have tracked it down.
 
Good advice Telectrix, a wander lead is next on the shopping list.. I just got my Fluke T5-600 through the door this morning. I'm thinking I should maybe have got a wander lead first, considering I've got a Fluke i410 clamp & T140 already! :-/
 
in the absence of a wander lead. just buy a roll of 1.5mm single cable. use that. and deduct the resistance ( about 1.5 ohms or thereabouts) from your readings.
 
I'm going to buy one anyway. I need one for testing bonding etc...

I'll put a 20amp breaker in it for now and look at it when I get the chance!

Thanks for your advice, much appreciated! :)
 
Just because they are in the same mcb doesn't mean they are the right legs, been to numerous where the ring has been mixed with the immersion. Can you see the cables are he right ones if not I would try the lives to the other mcb's and the Cpcs to the bar and see if this sheds any light on it.
 
Biff55,

It has been tampered with at some point that's for sure. There's many a tell tale sign at various points in the installation. Metal boxes that are unearthed with metal socket faces!! Broken bonding conductors, unsheathed cpc's at various points..

I even came across a socket outlet hanging next to the outside vent!! ... I'm beginning to suspect the ring has butchered! :-/
 
If it's been tampered with assume the worst and 100% test. As onions1066 says while your at the db just quickly test for continuity with the other circuits, you'll be surprised what you find. "Heinz Canned Worms"
 
That about sums it up, yeah!

We've only been in the house a year and finding all sorts...

Took down a door standard a few months ago and a mass of wiring came down (grouped), and judging by the shoddy connectors and absence of sheathing on the cpc it would clearly suggest someone had be screwing around with it! .. So much for rating factors when people just pull things apart and shove them together anyway!! :-/
 
That about sums it up, yeah!

We've only been in the house a year and finding all sorts...

Took down a door standard a few months ago and a mass of wiring came down (grouped), and judging by the shoddy connectors and absence of sheathing on the cpc it would clearly suggest someone had be screwing around with it! .. So much for rating factors when people just pull things apart and shove them together anyway!! :-/

Yes I'm saying you need to check you've got the correct lives and earths just because they are together it doesn't mean they are correct
 
Hi Onions1066,

You'll need to bear with me on this, like I said I'm not that experienced yet!

The conductors were all traced back to their respective mechanical insulation,
where the two neutrals were clearly identified from their respective legs, and were followed from that point to the board where they become joined. The same was done with the line and cpc's, which are seen following their line and cpc conductor to their point on the board. All were then disconnected from the board, isolating them completely from all other circuits. This tells me I'm testing between the two disconnected legs, two disconnected legs where there's continuity between the neutrals!! There's no evidence looking at the conductors (as they can clearly be seen coming from the mechanical insulation in which they originate) that they're mixed up!

Hope this makes sense? :-/
 
walk around with your Loop meter find the higest reading, remove socket, find broken conection, reconect it,, jobs done :)
 

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