I have a standard 4 bed house with an outbuilding which has power fed to it. The electrics are in "generally good shape" (i.e. no rubber wire etc) and I have had a new split load consumer unit fitted with each side on an RCCB main switch, with the lights not on a RCCB and the fridge / freezer on its own RCCB, so that another circuit tripping does not take them out with it.
Occasionally, like two or three times a year, one of the circuit trips out - it might do this two or three times (re-setting in between) over a period of a couple of hours then be fine again for another few months.
The problem is that it this occurs so infrequently that I can't build up a sample of tests to narrow down where the problem is occurring. If I had a selection of specialist test equipment I guess I could measure each circuit and item to test for earth leakage, but only have "basics" like a multimeter, scope (and a working but basic old uncalibrated PAT tester).
Can anyone suggest a course of actions and tests to help identify the problem with what I have got, or can I hire the necessary piece of kit ?
Thanks
Nick