Existing installation has voltage operated RCD mounted adjacent to meter before terminating into local consumer unit. A new plastic enclsure consumer unit with RCD's is to be installed that will be positioned approx 7 meters from meter. Looking at 531.4.1 it seemes to suggest that an RCD at origin is required unless class 2 equipment is used? In any event I will use an 80A double pole fused isolation to protect the tails and was going to use a plastic enclosed unit with no external metallic parts. Question is can I just use the 80A DP fused isolation unit or will I need to add an RCD say 80A/100ma after the isolator? (the consumer unit will have 30ma RCD's fitted to cover the various circuits).