In my property I have a split load board with earth protection on both sides, one of the circuits is a 3 core swa to the garage about 5 metres away from the house in the garage there is a small garage consumer unit 2 way X1 6amp the other 16amp for a radial circuit, the consumer unit has a main RCBO switch, the question is does the earth protection need to be there as there is earth protection at the house consumer unit? Is it just convenience ?