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Hi I need to provide power to 3 external buildings - a small flat and 2 barns - without the need for 3 separate SWA cables. In the main house, I already have a 100A 2 pole isolator switch between the meter and a Henley block. From the Henley block tails supply the power to the CU for the main house. I plan to have a 16mm2 SWA also from the same Henley block to feed power to the flat. In the flat, the SWA will enter a Henley block. From this Henley block, I will then have a feed to the CU of the flat and the other feed to the first barn. Same in the first barn where it has a Henly block and again 2 exits from it to the CU in the barn and the other providing a feed to the second barn. In the 2nd barn, the SWA simply goes directly to its CU. So, there is a "continuous" 16mm2 SWA cable that provides power to all 3 buildings with a feed into each CU per building from a Henley block (I have estimated the expected total load to be lower than 75A, which is the operating limit for 16mm2 underground). I would like to know if this sounds acceptable? I may even add an additional 2 pole isolator switch in each building to isolate each without affecting any other building downstream. The other query I have is earthing. The main house is a TN-C-S system. The flat is brick and the barns are wood (all on concrete bases). There is a water supply to the buildings and therefore 10mm2 bonding will be used. I assume it is fine to use an "exported PME" - to use the earth provided by the supplier (the earth in the house), rather than using a TT earth local to the buildings. Sorry if not clear, I can provide a drawing if required. Thanks Dave