I have just recently put a 3.5kw inverter a/c in the bedroom. It has been wired back to the the switch board on its own circuit. It is on a RCD with 2x 20amp pwr cb, 10amp light cb, 1 x 20amp a/c cb. It runs fine on the RCD but it trips like every morning while it has been on all nighT and there is no load on it at all. When it is not put on rcd and we turn the main switch back on the RCD trips straight away. Does anyone have any ideas
Cheers

Ryan, November 2009

if you have a split load board and the air con has been taken off the protected side then the problem is in one of the other curcuits as it cannot trip if it is not connected to the rcd but a point to remember with a split load board is if you are moving you live cable to the unprotected side of the board the neutral cable also must be moved to the other neutral bar in the consumer unit if you have not done this then that is why the rcd still trips hope this helps

ritch, January 2010

"When it is not put on rcd and we turn the main switch back on the RCD trips straight away"

If it is not put on the RCD I don't see why the RCD would trip, assuming it is the air conditioner that is tripping the RCD.

Which country are you in?

Do you have a split load consumer unit or is the rcd incorporated in the main switch?

Do you know what supply type you have, ie do you have your own earth electrode in the garden?

Adam, November 2009