Thx dpc for your reply. I did check it and find it in IEEE 80-2000. Another question, If the customer does not have the drawing of the ground grid layout, what do I advise him to do so I can pursue with the study?
Hi - You can't do a grounding study without a drawing of a ground grid - Every ground grid can be different. You need to at least get a drawing of the station area from the customer, including everything to be within and adjacent to the ground grid area, then lay out a ground grid, then take into account soil resistivity and required step and touch potentials based on maximum available fault levels, THEN do the study to see if your design meets requirements noted ..... Once the ground grid is constructed, you should also measure the total grid resistance to confirm that it meets the design resistance...
Hi Veman,
Can I ask the customer to get one of his technicians to track the ground grid rods and bare conductors and provide me with the following:
1. The Rods (material, length, and size)
2. Ground grid conductors (material and size) connected, and the spacing between their connections.
3. The size and depth of the mesh relative to the grade level.
4. Detailed drawing/ sketch with all the distances between ground rods, with exact run of the bare conductors to the substation
You can ask, but if there are no drawings, the customer will have to do a lot of work to get useful data. It is probably not practicable to excavate to locate the ground grid conductors and rods. You can use cable location techniques with test signal injections into the grid.
A paper was presented at the CDEGS 2003 User's Conference on this subject, Assessment of Earthing Systems at Existing Substations. You might be able to get a copy from SES
My company is a customer of SES and gets the proceeds of the user's conferences for our use. It is copyrighted, and obviously, from their response to you, SES would object to it being copied and distributed.
Give it a rest. Try doing some independent research. It's not like some deity appointed SES as the keeper of all grounding knowledge. They are just one company.
I'd try searching IEEE Power Engineering society papers. You can purchase those if you find one that looks helpful.