Hello,
I have been searching IEEE 80-2000 and 142-2007 for references about construction metallic parts treatment as grounding electrodes and the information is few.
I am assuming that every metallic part must be joined to the grounding electrode grid (in bare copper) and so it becomes part of the electrode. But, if you have rebars in concrete, as they form a very dense grid (separated about 20 cm or less), do you still need to bury a copper electrode below the concrete? I am considering and external copper ring and connections to rebars, footings, piles, from that ring.
Returning to the rebar topic, one could determine that at such dense grids, you will not have any problems with touch and step voltages at all. I would only bury a copper conductor if I needed to connect some equipment grounding to it and I am very far from the outer copper ring.
And last, I have a question about concrete resistance. I have read in previous threads about it. I read it also in the above standards but they are not consistent with regulations in Spain, where concrete resistivity is given a unique value of 3000 ohms*m, and asphalt for example, 10000 ohms*m (this one coherent with ieee std 80 and 142). Has any of you any explanation for this?
Thanks.
I have been searching IEEE 80-2000 and 142-2007 for references about construction metallic parts treatment as grounding electrodes and the information is few.
I am assuming that every metallic part must be joined to the grounding electrode grid (in bare copper) and so it becomes part of the electrode. But, if you have rebars in concrete, as they form a very dense grid (separated about 20 cm or less), do you still need to bury a copper electrode below the concrete? I am considering and external copper ring and connections to rebars, footings, piles, from that ring.
Returning to the rebar topic, one could determine that at such dense grids, you will not have any problems with touch and step voltages at all. I would only bury a copper conductor if I needed to connect some equipment grounding to it and I am very far from the outer copper ring.
And last, I have a question about concrete resistance. I have read in previous threads about it. I read it also in the above standards but they are not consistent with regulations in Spain, where concrete resistivity is given a unique value of 3000 ohms*m, and asphalt for example, 10000 ohms*m (this one coherent with ieee std 80 and 142). Has any of you any explanation for this?
Thanks.