I've got an ongoing problem with a randomly tripping RCD.
It started 3 months ago, lost power in the middle of the night. 3 circuits (sockets/cooker/shower) fed by the one RCD.
Initial thoughts were to faulty appliances. But, the trip has been random, apart from it is usually late at night/early morning.
The trip is usually sometime between midnight and 2am. It cannot be pinned down any closer as the flatowner is in bed!
Once reset, it stays on for a week or more.
So far: All fixed wiring has been tested, and all OK. RCD (old Crabtree, plug in type, 15-20yo) has been changed and
ramp/time tested, 27mA ramp, 18/43 time. Earth leakage with my basic meter gave a 6mA reading.
It went again last night after a month of non-tripping.
I think I've covered all bases, and will now be changing the CU for a metal clad all rcbo board.
So, what do you reckon? I'm stumped now, and thoughts have turned to radio interference causing the RCD to trip.
It's a long shot, but I cant think of anything else that may cause it.
Any thoughts?
