Hi 18” down in a swamp likely is plenty for conductivity. 18” down in a sandy desert (or on an ice sheet) may be way short in terms of conductivity :) The real answer to any of this is “that depends”. (Yes, the ice sheet grounding problem is from a real case that shows up in some class notes from way back ….).
Some locations get multiple hits on a weekly basis in the summer. Other locations get a close strike once every few decades. What makes economic sense for one probably does not make sense for the other…. A “full up” protection setup can easily run into hundreds of thousands of dollars. I’d much rather spend that kind of money on a Maser … or two …. or three :) …. this is TimeNuts after all …. Bob > On Jun 19, 2018, at 10:56 AM, Scott McGrath <[email protected]> wrote: > > The 18” inch requirement is partially for damage resistance and partially to > ensure adequate soil moisture for conductivity. > > Content by Scott > Typos by Siri > > On Jun 19, 2018, at 10:50 AM, jimlux <[email protected]> wrote: > > On 6/18/18 6:39 PM, Glenn Little WB4UIV wrote: > >> To do the grounding correctly, all connections exterior to the building are >> to be welded. >> The cable to ground rod welds are to be 18 inches below grade. >> The exterior cable is to be number 2 copper or larger. >> To bond numerous ground systems together, a number 2 copper cable is to be >> buried at 18 inches and welded to each ground system. >> If using eight foot ground rods, a ground rod is to be driven every 16 feet >> along the connecting cable and the cable welded to the rod. > > > It helps to know *why* some requirements exist - I suspect the 18" burial > requirement is to avoid accidentally digging it up or damaging it. I can't > think of an electrical reason for it. > > >> A lot of work, but, cheaper, in the long run, than continuing to >> repair/replace equipment. > > It depends > > Unless you're doing geodetic or precision timing work with a 2 or 3 band GPS, > replacement GPS antennas are cheap. > I'd worry about the receiver and related equipment, but the antenna itself > might be sacrificial. > > As always, there's a risk/budget tradeoff > > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://lists.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
