OP
SimpleSimon
A fault downstream of the two RCDs will trip either or both.
A fault in between the two would only trip the upstream one. (This is why we place the RCD at the origin of the circuit in special locations.)
I would suggest that the next time the RCD/s trip, they switch off all the MCBs in the caravan, then reset the first RCD, then the second RCD, and if both reset, switch on each MCB untill the fault returns.
If they are able to identify the MCB where the fault occurs, then they should attempt to identify whether it is an appliance or a fault in the circuit causing the fault.
Disconnect or turn off each appliance, reset the MCB etc.
This is what i was telling them.to.do over the phone. Told him turn off all MCBs turn on all RCDs and turn it on one by one. He said he did that and there was no power at all, nothing tripped but no power. RCD in caravan blown? Doubt it, think its just him. But when he turned caravan sockets on after a couple of seconds outhouse RCD went. There i think is the answer.
They think the fault is in between the RCDs but im telling them its not, its in the caravan.
Sent from my GT-I9100 using Tapatalk