Incoming Earthing

Steve1968 · Jul 1, 2013

Hi I live in the Highlands of Scotland and I am doing a EICR. The main supply is a 2 core cable supplying phase and neutral and a seperate bare earth wire. I cannot tell if this earth wire goes to an earth rod or to the distributors earth system. How can I check this. Thanks

trev · Jul 1, 2013

PEFC and PSCC, if they're the same (give or take) then it's TN-C-S. If Ze is above TN-C-S limit but below TN-S then it's possibly TN-S. If it's way over then think TT.
Given that it's out in the sticks I'd be expecting TT

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Just re read the question, does the bare earth go to a clamp on the incoming cable?

Engineer54 · Jul 1, 2013

Steve1968 said:
Hi I live in the Highlands of Scotland and I am doing a EICR. The main supply is a 2 core cable supplying phase and neutral and a seperate bare earth wire. I cannot tell if this earth wire goes to an earth rod or to the distributors earth system. How can I check this. Thanks

Well, ....if the earth conductor doesn't originate at the service head or from the incoming DNO cable sheath then it must be coming from an earth rod or other form of earth electrode!!