Fault Find - advice please!

[DPG]

Happy hunting! Keep us posted with what you find.

 

[Richard Burns]

Thanks Richard, just to answer your question, I did test with the earths connected. I took the neutrals out, but the earths were connected.

I thought the fault might be a component in an appliance that isn't running constantly like a fridge compressor or a heating element in the washing machine etc.

Really appreciate the feedback - thanks

OK then it might be worth testing IR: line on your side to the other neutral bar, or if there are too many loads just between neutral bars with the RCDs out of circuit and MCBs On, main switch off, to see if there is a connection across circuits. This would allow some current to flow down a different path and trip the RCD, however if the circuits are all well separated and the other RCD is not tripping then this is less likely.
If the RCD is tripping with any load then it is likely to be a circuit issue rather than an appliance.