Live neutral wire in socket

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Hi,

This is going to be sorted by an electrician tomorrow but is puzzling me tonight!

Started fitting a new kitchen today, part of job running cables in for 2 new sockets in existing ring.

Took one of the T+E from existing socket and connected to a JB, T+E from JB to new socket 1, T+E from new socket 1 to new socket 2 then T+E back to the original existing socket to rejoin the ring.

Issue I ended up with was that when the ring was split (e.g. at the JB) I had a 'live' neutral and phase wire at the original existing socket and it no longer worked - sockets on other side of the ring were still working though. Reconnecting the ring caused the 'live' neutral to go away and all sockets worked again.

Spark says it may be borrowed neutral? Can someone explain how the neutral wire becomes live in this scenario?

Cheers
 
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What were you using to test it to be live? Live compared to what?
What flyingsparks asked ...

... t sounds as if the neutral of the JB side of the risk has probably got a loose connection somewhere, hence is not connected to neutral at the CU. If there is any load connected to the part of the ring (and the L is connected at CU), then you would get line voltage appearing on the neutral at the JB (via load from L). When you complete the ring, that faulty part of the ring would then get a path to neutral at th CU via the intact part of the ring. It should be easy for an electrician to diagnose with a few tests.

Kind Regards, John
 
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Took one of the T+E from existing socket and connected to a JB
Why?

Why not? I have extended a ring to two new sockets, new cable from existing socket, in and out of the new sockets then back to the JB to reconnect to the ring. Are you suggesting this is wrong? Admittedly a new length of cable to the next existing socket on ring would have been 'better' but only one socket in room I'm working in so JB was a lot easier!

JohnW2 - spot on there was a loose N wire in a socket in another room which was causing the fault on that side of the ring.

Cheers for the help and look forward to finding out what i have done wrong above :)
 
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Be sure to use maintenance free junction boxes, if you are jointing where the joints cannot be accessed for inspection, test and maintenance.
Also be aware of the requirements for permitted safe routes and RCD protection.

The question I would be asking, is did you not discover the presence of a loose/disconnected neutral whilst dead testing the ring?
 
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Why not? ... Are you suggesting this is wrong? Admittedly a new length of cable to the next existing socket on ring would have been 'better' but only one socket in room I'm working in so JB was a lot easier!
Yes, I think that's probably what he was suggesting - what he would call 'good workmanship'. Mind you, most of us here would probably agree that, whenever possible, JBs should be avoided - since (as you've just discovered!!) loose joints/connections do arise - so the fewer the better! ... talking of which, is this JB going to be accssible for inspection, testing and maintenance? If not, it needs to be a 'Maintenance-Free' JB.
JohnW2 - spot on there was a loose N wire in a socket in another room which was causing the fault on that side of the ring.
Ah - it's nice to be right for once! It did seem to be by far the most likely explanation for what you were describing. Glad it's sorted!

Kind Regards, John
 
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Yes clearly not! Like I said sparky was coming to connect new sockets back up I just wanted to be able to put the power back on so the exiting sockets would still work (as 2 radials) which led to the issue with the neutral.

Can I just ask after looking up 'dead testing' would a spark carry out all of those tests to install one or two new sockets every time?

How long does this take on say avg 3 bed house, those tests say everything must be unplugged etc, no neons present etc etc?

I ask this seriously as I have a property maintenance business and have been thinking of doing some electrical training so I can do more electrical work myself instead of having to sub it out.

btw - the JB is accessible
 
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Can I just ask after looking up 'dead testing' would a spark carry out all of those tests to install one or two new sockets every time?
One would hope that (s)he would at least do continuity tests to make sure that 'the ring was a ring' (which yours obviously wasn't, whilst the neutral fault was there - so it would have picked up that fault) - which would probably only take a few minutes. Hopefully, they would also do all the other 'dead tests' - but, again, for just one circuit that would not take very long.

Kind Regards, John
 
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