Intermittent sockets, wiring and fuses fine

[Lorzor]

I had a quick job yesterday where the customer said he lost power to some kitchen sockets, I went round and he had an old wilex board with rewireable fuses. All the sockets in the house were on two 30A fuse wires. Most sockets in the kitchen were in a ring on 1 and the rest of the house must have been on the other (oddly there were some sockets in the kitchen on the other too). I didn't do any testing on the other circuits and the fuses were fine.

Basically all I did was remove the 5 affected sockets and check the wiring in them, they were all fine apart from one where some of the cables were loose, I reconnected it and did an IR and all was fine. I replaced the fuse and all the sockets were working. Even though the wires came out they only came out when I removed the socket from the pattress but I thought that must have been the fault.

Except they rang me this morning to say it has happened again and it was when the dryer was on, they also said it happened last time when the dryer was on.

How can they have a complete loss of power (less than 1v measured) on these sockets if the wiring is good and the supply is good? Bearing in mind I managed to remake the circuit just by removing some sockets and removing a fuse then replacing them. I just want some ideas of where to start when I go back tomorrow. All I can think of IF the wiring is definitely good is some kind of thermal cutoff switch hidden away somewhere. I think that's pretty unlikely - could there be some connection issues in the old board?

 

[SJD]

If it were a lose connection on a ring final I would not expect several sockets to be non functional unless they are a radial.

Well perhaps there are several loose connections, and what is supposed to be an RFC has already one or more breaks, possibly intermittent ones. When at least two connections go open circuit on L or N, the power is lost?

 

[Richard Burns]

I would suggest that end to end testing of the ring to start with would be a good idea.
Losing power on a ring is not common without something else wrong.
I would suspect there was a joint overheating somewhere on loading the circuit and that the ring had been broken at some point, or it is a lollipop ring,but that is not so from your description of the circuit.

 

[Dave OCD]

Have a look inside the Wylex too, check the integrity of the connections and make sure nothing is overheating in there.

 

[Octopus]

Back to basics is the place to start...

Just done an EICR where a few sockets worked on and off - rocking my tester in the socket confirmed, in each case, that the sockets were knackered.....

 

[Pete999]

Back to basics is the place to start...

Just done an EICR where a few sockets worked on and off - rocking my tester in the socket confirmed, in each case, that the sockets were knackered.....

"Rocking my tester in the socket" what does that mean?

 

[Octopus]

Plug the tester in.... Notice it's loose, and watch the readings of the volts change as you change the position of the plug in the socket....

 

[Pete999]

Plug the tester in.... Notice it's loose, and watch the readings of the volts change as you change the position of the plug in the socket....

Right thanks.

 

[FatAlan]

Pete. Haven't you heard of a shake, rock it, socket and see tester? Almost as good as Megger

 

[telectrix]

almost as good as my hammer method. if it works when you hit it, it's loose.

 

[Pete999]

Pete. Haven't you heard of a shake, rock it, socket and see tester? Almost as good as Megger

Heard of a socket tester, and I knew what the OP meant, I thought it was street talk for putting his socket tester in, nearly went to my post box to see if the postie had rocked some letters in for me

 

[GREEBO]

"Rocking my tester in the socket" what does that mean?

Its a technical term.

 

[Pete999]

Its a technical term.

Dumbest technical term Ive heard of.

 

[telectrix]

here's a nice technical explanation related to fault finding. it concerns the conversion of kinetic energy and Newton's Law which states that for any action, there is a corresponding equal reaction. basically put into layman's terms, this means to hit it with a hammer and see if it works.