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Cross sectional area of a protective conductors

MS01
Can someone give me a some advice on if we have a earth electrode system made up of the structural rebar when using the adiabatic equation to size of the bonding conductor comes out at 300mm. MY questions is does each bond need to be this size or can it be made up via a series of smaller bonds that are equal or exceed the 300mm requirement? My opinion is each bond needs to be this size to deal with the fault current as the direction it will flow is unknown. What are peoples thoughts? I cannot see anything in the regs on this.

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    Well 1.39 ohms, (by the way, a surprisingly precise number,  is that a test result or calculation ?) will pass less than 200A  into earth, assuming we are talking about the bit of cable that only goes to the electrode. As such, even if the fault was never cleared, in practice a piece of 50 or 70 mmsq would probably do. The stuff that does carry the full fault current is going from the supply neutral to the CPC that goes to the enclosures for the live parts. I presume the 90kA fault current does not go very far before the impedance of the cables themselves reduce the prospective fault current quite a bit.
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    Well 1.39 ohms, (by the way, a surprisingly precise number,  is that a test result or calculation ?) will pass less than 200A  into earth, assuming we are talking about the bit of cable that only goes to the electrode. As such, even if the fault was never cleared, in practice a piece of 50 or 70 mmsq would probably do. The stuff that does carry the full fault current is going from the supply neutral to the CPC that goes to the enclosures for the live parts. I presume the 90kA fault current does not go very far before the impedance of the cables themselves reduce the prospective fault current quite a bit.
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