Has anyone here got experience of doing a soil / earth resistance survey for the design of a large-ish site? We might be looking at a fenced area of 150 x 40m or so with possible need for lightning protection and/or input to the decision to have the substation within the site or far enough out that hot/cold separation of LV/HV earths is possible.
I was thinking of getting the Megger DET4TCR2 and their ETK100 probe kit (though a bit galling how much they charge for a few reels of wire and some spikes!) if this is likely to happen as we would need it at a few stages: design, initial testing, and then on-going checks on earth electrode impedance, so longer term its probably better than hiring. But have no experience of those 4-electrode testers to know the good, the bad, and the ugly.
TL;DR any helpful suggestions on measuring soil impedance profiles?
I was thinking of getting the Megger DET4TCR2 and their ETK100 probe kit (though a bit galling how much they charge for a few reels of wire and some spikes!) if this is likely to happen as we would need it at a few stages: design, initial testing, and then on-going checks on earth electrode impedance, so longer term its probably better than hiring. But have no experience of those 4-electrode testers to know the good, the bad, and the ugly.
TL;DR any helpful suggestions on measuring soil impedance profiles?