rcd tripping for no apparant reason i have checked all ccts ok the supply is a TT sysyem and so are the neighbours. earth rod fitted. measured tripping current using ramp test, tripped at 21mA. checked at 1/2 tripping current no trip untill pc plugged in. however rcd has tripped with pc disconnected. could a fault on the neighbours ccts affect my rcd through the common earth. the problem is much more apparant in the wet weather.