0.13M ohm between CPC and Neutral!?

[eveares]

Hi all, woke up this morning to a buzzing and crackling sound coming from one of the sockets in my bedroom when I turned it on, which also caused the lights to flicker at the same time, what is the 2nd socket inline on the 20A radial socket circuit. Stuff was not working/powering up on this socket, but was on the 3rd socket in line.

Decided to test the 1st socket fed directly from the DB, and my all in one socket tester failed the test and then a moment later tripped the RCD. Then isolated the circuit at the DB and removed the first socket, IR reading between L and CPC was 0.13MΩ Other two downstream cables from this first socket were fine from a IR perspective.

Obviously this cable from the DB to the first socket on the 20A radial circuit is damaged (and is going to be a pita to fix), but would this low IR reading between N and CPC cause the crackling and buzzing sound on the socket and the lights to flicker?

Regards: Elliott.

 

[chivers67]

IR reading between L and CPC was 0.13MΩ

I thought from reading that your test was on L to E not Live to Neutral? Or are they both too low?

Did you remove the cable completely from from the Socket terminals and DB? It isn't fed via a FCU with a Neon is it?

 

[eveares]

It's ok, I sorted the issue.

The socket what I thought was fed from the DB, was in fact the 2nd or 3rd socket inline and the socket what I thought was second in line by my computer, was in fact fed directly from the DB. I made the wrong assumption initially based on the socket being closest to the DB physically - It's been 10 years since the extension was built and I saw how the cables were run during the first fix stage.

The low IR reading was caused by a submersible sump pump that was plugged into the outside socket, that is fed through the wall from the first socket in my bedroom (that is fed from the DB), what was the one that was buzzing. I replaced this socket in my bedroom by my computer and when I did, it had burnt neutral conductors inside.