Thanks for the reply ericmark - just to elaborate the RCD is 80A 30ms. Main switch is 100A and supply fuse is 100A. I need to replace the cable between main switch and RCD as I can see the bare conductor and the cable is too short to re-adapt. The existing cable looks to be 10mm and has the words 'Live Supply 80A max'. I thought about replacing with a 10mm core of twin & earth but this is not as flexible as the existing cable - so is there a different spec of cable used for this function?
Yes special cable is used with double insulation. In general a wire is used where there is protection as inside conduit or trunking and where there is no protection than some form of double insulation is used. Twin and earth has the grey outer and this should not be removed unless it is inside some protective device like a socket box or consumer unit. 6181Y 25mm Cable 5m Brown/Grey and 6181Y 25mm Cable 5m Blue/Grey cost around £13.12 each so would not think £26.24 is really going to break the bank? (Screwfix price) they are listed as Meter Tails
PVC insulated single core Meter Tails (6181Y). For connecting CUs (Consumer Units) and switch fuses. Harmonised colours. So can't really make any mistakes getting right stuff.
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