Hi, There's this double socket in the tack room of an old stables. It's fed individually direct from the CU in the workshop next door. There is nothing else on this circuit although another radial is wired into the same 16A breaker which feeds another double socket in the storeroom next to the tack room. The tack room socket started tripping the RCD whenever put under load. At first I though an appliance fault until I tried a lamp, a drill, and an angle grinder all of which tripped the RCD when plugged into the tack room socket and all of which work fine when plugged in elsewhere. So I powered down and took the socket apart finding no visible fault in the wiring or connections, everything tight, no insulation damage etc. So then I replaced the socket thinking well maybe that's faulty, but no, same thing happened. So what might be the possible causes of such a fault? Earth leakage across the whole system? Any suggestions as to what possible causes of this fault might be? Thanks in advance.