A qualified electrician will understand the Adiabatic is the last part of any electrical calculation. After that test & inspect. The distributor may require a minimum size of earth conductor at the origin of the supply of 16mm² copper or greater for TN-S and TN-C-S supplies. b) Bonding connections to incoming metal services should be made as near as practicable to the point of entry of the services into the premises, but on the consumer’s side of any insulating section. c) Where practicable, the connection to the gas, water, oil, etc service should be within 600mm of the service meter, or a point of entry to the building if the service meter is external and must be on the consumer’s side before and branch pipework and after any insulating section in the service. The connection must be made to hard pipework, not to soft or flexible meter connections. Would I consider sizing it to half of the combined area of the 3 (240mm2) size as in half of 720 mm2 or half of each 240mm2 .

Time 6491X Green/Yellow 1-Core 16mm² Conduit Cable 25m Drum

For your convenience, we cut to the length you require. Simply select the number of metres you require. The main protective bonding conductors shall have a cross-sectional area of not less than half that required for the earthing conductor and not less than 6mm².Yesterday I commented that there was almost no detail in the question and the answer referred to a 2.5mm2 earth. Now there is more detail in the question, and the answer doesn't refer to 2.5mm2 - but some of the earlier comments do which suggests the answer has been edited again. It almost looks as though the answer is to a different question. probably best to delete it and start again? Hi As an old timer I take the view in this case that if you have a demand 1200 amps plus a possible fault currant, then the earth conductor should be able to assume the same load & potential fault. If all else failes then the cables becomes the fuse? I have an install involving 3 four core SWA of 240 mm2 feeding an MDP from a generator.The load is 1200 amps.

Earth Bonding Cable Size Selection | Eland Cables Earth Bonding Cable Size Selection | Eland Cables

This 16mm² Single Core Earth Cable is suitable for power and lighting circuits, building wiring, use in conduits and closed installation ducts and internal appliance wiring. The 6491X cable comes in a 50m drum. When calculating the size of the protective conductor do I use Table 54.7 or the Aidabatic equation?

The whole point of an Adiabatic equation is to save money over hundreds of cable runs ! THAT'S IT. If your doing one or two runs and the cost isn't important then fair enough, use the standard size in the wiring regs as a guide. Protective conductors (including earth and bonding conductors) of 10mm² cross-sectional area or less shall be of copper.

Earth Cable 16mm 6491X Per Metre · Quickbit Electrical UK

is a non standard size protective conductor size, so the next size up is 10mm2 is acceptable, which saves money installing a 16mm2. The most typical method chosen is selection, in accordance with table 54.7 and the size selected is based on the cross-sectional area of the line conductor. For 25mm tails this results in a 16mm main earth. Using regulation 543.1.3 and the calculation method, the size of the protective conductor chosen is typically smaller than through selection. In the situation, you describe the calculation would need to be completed to determine whether the earthing conductor is adequate. If you use 54.7 the earthing conductor would be 1/2 of the line conductor ie 120mm. Its based on one line conductor as it is fault current to earth we are looking at. The size of an earthing conductor shall be in compliance with regulation 543.1.1. This requires either:Guidance on earth conductor and protective bonding conductor cross-sectional areas is given in the guide to the wiring regulations BS7671.