Live - Neutral reverse from plug in tester

Sparkingchip: 
 

The answer is to drop the circuit out of the consumer unit and test it starting with end to end continuity tests and go from there.

Fault finding with a plug in tester and a multimeter is not impossible, but it’s a bit of a nightmare.

If you are going to do that drop one end of the ring out a make it a radial for testing as it’s a lot easier to test a radial, then reassemble the ring after clearing the faults.

Note that some multimeters have a “LoZ” setting or similar, which measures voltages while providing a (relatively) low impedance to the load. On my fluke it's enabled by holding down a certain button while switching on.

Finally sorted fault. found on the ring one socket had very loose cpc wires so not forming the ring it does not help when electricians don't twist them together, if they did but not terminated at least the ring would e maintained to other outlets.  Then at i expect an adjoining socket but on other side of room one of the cpc ring earths was left at back of box, looks like it was never put into the terminal, again if they were twisted together first then its unlikely to be forgotten.

In my 50 years of sparking and notably more in the past 15 years its my  educated guess from what I've found that around 80% of houses have electrical faults, that is shocking (not a pun). For all the regs etc in the UK things are getting worse and not better. The Industry needs to change dramatically to rectify this. The perceived protection from having Part P or even 16th;17th or even 18th regulations has proven to be useless in 80% of works i have experienced.    I think the IEE as it was, the government and through them councils have let the general population down very badly.  It may be said you cant go back to the old ways but this Anew way could be costing Lives, mostly children who can be inquisitive. Relying on modern RCD protection is Ok as long as earths and polarities are checked.   Even folks upgrading outlets or accessories need to do do a final plug in socket tester in case cables are left wronly or not connected as single core cables can break when being pushed back into box.

I hope the above gets to ears that care for our trade/profession. That it may help others understand why certain types of faults are detected and fixed.

Mikesparky: 
… it does not help when electricians don't twist them together …

Mikesparky, thank you for the feedback and the solution.

I take your point about twisting the CPCs together, but it does seem to be a practice which is deprecated nowadays.

it does not help when electricians don't twist them together, if they did but not terminated at least the ring would e maintained to other outlets. 

Twisting solid-core conductors is often considered poor practice these day - as it means damaging the conductors if they need to be separated for testing or fault-finding. On a ring a single fault won't loose Earth to other accessories since there'll still be continuity around the other side of the ring - but the fault would be easily detectable by a routine end-end test from the CU.

   - Andy.

AJJewsbury: 
 

it does not help when electricians don't twist them together, if they did but not terminated at least the ring would e maintained to other outlets. 

Twisting solid-core conductors is often considered poor practice these day - as it means damaging the conductors if they need to be separated for testing or fault-finding. On a ring a single fault won't loose Earth to other accessories since there'll still be continuity around the other side of the ring - but the fault would be easily detectable by a routine end-end test from the CU.

   - Andy.

I always twist the C.P.C.s of 1.0mm2 and 1.5mm2 together. It makes a good joint. If sufficient spare wire is left and the wires are damaged if untwisted, it is easy to re-terminate the wires if needs be. Single small solid copper conductors terminated into terminals without doubling the end over or twisting more than one together can come loose or indeed not be held in the terminal securely.

I always trim back any copper solid conductor that has been deformed by a screw, as if not, the wire can snap/break when moved about whilst refitting an accessory. This applies to untwisted single wires as well.

Z.

Sadly there are some truly dire installations out there, and unless I am unlucky in the ones I see, I would agree that things like part P and a ‘do not touch leave it to the experts’ advice is working against us - having customers who have enough knowledge to spot poor work is actually useful in preventing standards slipping too far at the shallow end. There is an unhealthy obsession with paper trails, registrations  and risk assessments, and not enough practical instruction of the basic levels e.g.  “give it a good pull, and if it falls out it's a failure so go back and re-do it so it does not” sort of level.

As a PS when the ring was first mooted in the 1940s some of the early advice suggested that the conductors of the ring should be unbroken. Now I presume this advice was not written by anyone with much practical nouse, as threading conduits or indeed just about anything, and stripping cores part way along at each fitting is a non-starter, but a solid twist became the way to ensure ring integrity. Only with the rise of testing in a way that requires unpicking the ring at regular intervals has the advice changed to wires side by side.  Maybe we will go all USA at some point in the future and start having a 1 wire one terminal rule, and thinner wires and radials.

Mike.

As a PS when the ring was first mooted in the 1940s some of the early advice suggested that the condutors of the ring shoult be unbroken. Now I presume this advice was not written by anyone with much practical nouse, as threading conduits or indeed just about anything, and s stripping cores part way along at each fitting is a non-starter

+1 for that - and the idea hasn't entirely gone away - certainly quite recently MK still produced a rectangular 30A JB specifically designed so that the main cable could be run through uncut. (Although that did beg the question of how to sleeve the c.p.c. to meet BS 7671 requirements)

   - Andy.

I like Blencathra's mention elsewhere of a sparks who meticulously soldered the ring at each accessory. I don't think that it would have taken very long to do.

However, if you do up the screws properly, and you do your proper ring tests before initial energisation, I don't quite see the need for twisting the ends.

Chris Pearson: 
 

I like Blencathra's mention elsewhere of a sparks who meticulously soldered the ring at each accessory. I don't think that it would have taken very long to do.

I don’t see why anyone would think that is a proper job.

526.9 states some definitive prohibitions.

I would go as far as saying that soldering conductors that will be terminated in socket circuit accessories is just plain stupid.