RCD "Supply Tripping" ?

Guys
Yes its that same ol topic once again...RCD tripping
The owner of the house tells me the 30 ma rcd started tripping daily ever since a storm 2 weeks ago and Western Power came out to repair a damaged overhead line feeding the premises

The combined insulation reading of the house with vereything connected is 0.2Megohms...Not good I know but too high to knock the trip off
Impedance is 35 ohms .I found that the RCD is tripping out at 20 milliamps
Ok so I changed the RCD and put a new Wylex one in
I tested this before installation in my own home and all ok

Damn when I got down to the property even this started tripping at 20 milliamps although it did "settle down and behave accordingly

I am wondering if anyone has any experience of the supply affecting RCD's cuz it seems strange that all this started after Western Power had done their stuff

I can understand that the above insulation test readings may not be helping but the original RCD had been put in about 10 years ago with minimal tripping and it seems a coincidence that all this has come about since the repair to the overhead supply

Cheers

Overhead supply... 35 ohms... = TT.

What else is on the 30mA RCD apart from sockets?

Also have a look for the reason for the low IR. Look for signs of water ingress too, lights etc. A figure below 2 meg isn't good.

ban-all-sheds said:

Overhead supply... 35 ohms... = TT.

What else is on the 30mA RCD apart from sockets?

Click to expand...

Everything is taken off the 30ma RCD The house does of course does need rewiring.
To be honest I have not done a full test on the place although most of the circuits are pretty low ...about 0.5 and two at 0.2 Mohms it is a major job just to get at the sockets to unplug them such is the clutter there

You know what people are like though ...they spend thousands on a patio and stables but wont spend on the wiring been thinking though of replacing the existing board and installing 8* RCCBO's....hehhe it would be cheaper to rewire the ****hole

Also guys I know this is dangerous but if I disconnect the main earth at full load and connect an ammeter in between the earth block and the main earth ..this should give me a reading of any earth leakage current? Add this to the 20ma that I am putting on to the circuit with the RCD tester and hopefully this would give me the reason why it trips out
Health and safety would have a fit
I am open to suggestions of testing earth leakage
Cheers