RCD tripping, can't identify the appliance

kimwp

Gosh, did they have a theory as to why the power outage precipitated the issue, or was it just coincidence! Glad it's diagnosed and thank you the update, always nice to know the outcome!

ThisIsWeird

Thanks for the update.
Blimey, so easy to assume a cause!

battenburg88

They didn't have a clear reason, no. The socket in question used an older piece of cable coming off the junction box and apparently this wasn't in very good condition. They think that perhaps the power cut, and the chance of there having been a slight power surge immediately beforehand, could have just tipped it over the edge. But no definitive answer so it will remain a bit of an expensive mystery.

It makes some historic work fit together a little bit though. When I moved in I had a safety test done and that identified that this circuit had an issue. As far as I understand it the electrician fixed this by cutting off the old circuit and rerouting a whole new cable to the back of the house. Apparently this cable newer cable looked ok and hadn't been chewed by anything, but seemingly they didn't change the older bits of cable that were just 'spurs'. 

I'm planning to get some renovation work done in this room on a relatively limited budget. This has made me realise that it might be better to use that limited budget and get the basics done properly. I can go without fancy kitchen units and nice tiles, but i'd prefer not to have to get fault finding done on the old electrics every few years!