RCD Trip

[marc8]

your old board saw all neutrals as common neutrals & your new consumer unit has 2 RCD's one neutral for each output of the RCD's installed although at the beginning they are common not on the outputs of each RCD, all as above really.

Thanks
I had initially discounted Neutral Earth as had not tripped on old RCD or the way I have Left it.

Had passed my brain as Neutral in wrong place. Which probably meant the initial installation ( some one else, before I bought the house) was wrongly labelled ( luxury) or they had crossed up a ring main. Neutral wrong place was my first thing to-
morrow. Thanks