Faulty socket, strange voltage reading on socket

[rockomuir]

Evening all,

Been to look at a fault today! Customer said a socket was not working. Plugged my tester in and instead of reading saying 230v on phase and 230 on earth I got a 230 on phase, 187 on Earth and 33 on neutral. I took socket face off to check it was not a faulty socket(which it was not). Only one cable in back box and could see that it went under floor . All other sockets on circuit work and readings are fine. The circuit is 32 amp 60898 and split load board. All sockets on circuit only have one cable so must be jbsunder floor. Informed customer I would be back in morning to investigate properly. 

Has any one had any experience of this type of problem before. Just wanted a few pointers before breaking circuit down ?

 

[ProDave]

What are your voltage readings with respect to?

Socket is obviously a spur so find out where it spurs from and check there for a loose wire(s) Sounds like lots of hidden junction boxes, good luck with that.  Did you do any end to end continuity testing of the ring?

 

 

[rapparee]

I'd say you have a broken neutral. When you say 230v on phase what do you mean by that. 230v between phase and what. 187v between earth and what etc.

 

[Murdoch]

Did you retest the voltages at the cables once the socket was removed?

 

[rockomuir]

Hi thanks for the replys.

With regards to testing and between what and what. I just popped my head in on way home from work. I just plugged in my  metrel on voltage setting to to see if it was totally dead. Instead of the display saying 230 L 230 Earth and 0v neutral as it would do normally do it showed the voltages I mentioned earlier. I will be back to do continuity etc in morning when house is empty. Not a lot of detailed info I know ! Just wanted to pick peoples brain ready for the morning.

 

[Murdoch]

What is normally plugged in the socket in question? Seen many with burnt out "insides"

 

[steptoe]

not having a metrel,

What were you measuring the voltages across,?

L-?

N-?

E-?

And were you getting a voltage on E or in reference to,?

The numbers you have are meaningless without a reference point, or polarity to.

 

[Evans Electric]

Interesting to see how its all connected under the floor Rockomuir .

If its just gone like that it could be rodent damage ,  loose connections , if he earth is not connected it'll show all sorts of voltages. Best of luck with it anyway , let us know how it goes. 

As said above , check the actual wiring with the socket off  before ploughing on . 

 

[ProDave]

Hi thanks for the replys.

With regards to testing and between what and what. I just popped my head in on way home from work. I just plugged in my  metrel on voltage setting to to see if it was totally dead. Instead of the display saying 230 L 230 Earth and 0v neutral as it would do normally do it showed the voltages I mentioned earlier. I will be back to do continuity etc in morning when house is empty. Not a lot of detailed info I know ! Just wanted to pick peoples brain ready for the morning.

I certainly hope it would NOT normally say 230 Earth.

Start with R1, R2 and Rn that should tell you everything.
 

 

[Lurch]

I would suggest that you actually learn how to use your tester properly before returning and maybe look up what the voltages should be between conductors, and maybe actual learn basic electrical things liek an electrician would.

Why the hell would anyone turn up at a job, shove a tester in the wall and then leave?

Have you actually had any training?

 

[Andy™]

Have you actually had any training?

yes, plug it in, if it says OK its good. end of lesson