RCD Tripping

[Ash1991]

Sorry for late reply I've been working all day.

So after looking again when I wasnt as tired I've realised the fault is with the kitchen ring main. If the kitchen ring main is connected to the fuse board whenever anything on any circuit is turned on (including the other side of the fuse board protected by a different RCD) the RCD protecting the kitchen circuit trips.

The cables go from the fuse board under the stairs up to the bathroom and back down into the kitchen. I've had work done in the bathroom and the kitchen was tiled yesterday so the sockets were disconnected for a few weeks waiting for the tiler (delayed in turning up) before being refit and power turned back on after tiling and that's when I've realised the problem.

Plug in tester shows no problem at any kitchen socket and inspected the back off all sockets and all the wiring is correct with no loose connections.
After disconnecting the cables to make sure it was defiantely what was causing the RCD to trip (it was). I connected just one cable to turn it into a radial to see if there was any sockets that were then dead to maybe narrow down the problem.

When it is connected as a radial all the sockets had power and the rcd is not tripping even when running multiple things on different circuits

 

[ericmark]

If the kitchen ring main is connected to the fuse board whenever anything on any circuit is turned on (including the other side of the fuse board protected by a different RCD) the RCD protecting the kitchen circuit trips.

That looks very much like a neutral to earth fault, it could be the 3.5 mm screws holding one socket pushing against a neutral wire, but if you can't see a fault, then it is a case of testing.

When my daughter had this problem it way a case of split in two and find which half had fault, then split that half in two and so on until found faulty socket, which turned out some one had be careless stripping cable an the holding down screw was touching the neutral cable.

I could not find my mega so bought new one it cost £35 but that was cheaper than hiring one, as to hire it needs to be calibrated after each hire, so actually cheaper to buy non calibrated than to hire a calibrated one. Note they use 250/500/1000 volt, so one does need to be careful using one.

 

[Murdochcat]

Tiled yesterday is probably a starting point

 

[ebee]

"When it is connected as a radial all the sockets had power and the rcd is not tripping even when running multiple things on different circuits"

Does this mean with kitchen sockets hanging loose? because connected as a ring or a radial would have two conductors touching or not so the same would be expected to happen unless one (or more) of the sockets back in position is actually causing the problem - usually in the box area behind the socket or near to the socket itself but it also be somewhere near to where the T & E sheathing is split just inside the box - it could also be slightly outside the box if the sheathing is split too far, all the changes in tension on conductors could effect whether they are just touching or just not touching.

It could actually be just inside a faulty socket , more so if a cheap make of socket, I`d not suspect that with a decent make.