Just thinking very long-term maintenance with no current problems or readings, in a small 1970s 4-storey block of flats, TN-S, with locked riser cupboards on each floor...
Would it be wise or completely unnecessary to run an earth cable up inside the 1970s steel trunking, and connect it to the trunking at each level?
The trunking is in perfect condition visually, and provides earthing to the flats on each floor via visible trunking and some hidden steel conduit concreted in.
Would a cable be considered "earthing", so could have separate pieces of cable, one floor high with cable lugs at each end, daisy-chained up the building?
Or would it be considered a sort of '"bonding", so the cable could not be cut at each floor, but could be stripped, and maybe fixed to the trucking with split screws? (That might be just as easy anyway.)
What calculation for csa applies, or isn't there one, so use 16mm?
Maybe in the future there could be cables also added through to each flat.
Would it be wise or completely unnecessary to run an earth cable up inside the 1970s steel trunking, and connect it to the trunking at each level?
The trunking is in perfect condition visually, and provides earthing to the flats on each floor via visible trunking and some hidden steel conduit concreted in.
Would a cable be considered "earthing", so could have separate pieces of cable, one floor high with cable lugs at each end, daisy-chained up the building?
Or would it be considered a sort of '"bonding", so the cable could not be cut at each floor, but could be stripped, and maybe fixed to the trucking with split screws? (That might be just as easy anyway.)
What calculation for csa applies, or isn't there one, so use 16mm?
Maybe in the future there could be cables also added through to each flat.
