In article ,
Hzatph wrote:
We have a newly installed RCD that trips in a very puzzling way. Let me
explain.

We have two separate consumer units. One has a split load RCD and
supplies the back of the house - it has never tripped. The other is an
older "fuse wire" consumer unit with 16 circuits supplying the front of
the house. It is protected by an RCD on its incoming feed and it is
this RCD that trips several times per day.

There is no single cause that trips it - sometimes it is a light,
sometimes the computer, etc. What is really puzzling is that the TV can
trip it. The TV is in the back of the house fed from the other consumer
unit and therefore is not even supplied through the troublesome RCD.

Is there any equipment which could cause the earth from one CU at some
point to to be shared with the earth for the other somewhere else? I
realise both CUs will share an earthing point.

Perhaps an aerial lead from a DA? Hi-Fi equipment interconnection?

--
*Nothing is foolproof to a sufficiently talented fool.

Dave Plowman London SW
To e-mail, change noise into sound.