I have noticed my C/U does not have a D/P isolator in the board and everything is covered by the RCD which is being used as a isolator. I know the dangers of this if somebody was to get shocked and turn out all the lights. leaving us in darkness in a time where we need light the most. But is the board actually done wrong. do I have to have a split load board?? also could these lead to nuisance tripping? look forward to hearing your advice