Robert, At my installation the only one I am really concerned about is the ground for the DSL into my house (NOT installed by myself) that is a pipe, not a rod. I clamped a ground wire to a sanded portion of the pipe, and bonded it to my station ground, but I think the pipe thing is a real bad idea. Given that it is an AT&T thing, do you have any suggestions other than what I have done? Ron Sent from Mail for Windows From: Robert Polinski via BVARC John, they do make thread together rods, when I did commercial communications I have used them at comm sites. Here, a 10ft ground rod is fine as are wet gumbo soil makes a pretty good ground. The NEC requires 2 ground rods or a ground rod and a ufer ground, which can be rebar in the slab, metal water line or metal bldg. if in contact with the earth via rebar or poles. I usually install 2 rods. Most 10 ft ground are easy to push in the ground with just your hands. I just a few weeks ago installed additional rods at a hams house in the Heights. I wired a home in Elgin, just outside of Austin. Had to install horizonal ground rods as the ground was solid rock 2 ft down. I always tie to an existing rod but always add an additional rod as you never know if the old ground rod is 10ft or 18” Here in the Houston area, testing is not necessary because of the soil, but as the video shows, it is a neat test. You are correct in your bends in the grounding conductor, they will act as a choke if made sharp, also, you should no run the ground wire in metal conduit for the same reason unless you bond the ground wire to the conduit at both ends. As far a lightning goes, remember, all the wiring the strike travels thru on the way to the earth has resistance & inductance, so by the time it gets in the circuit the voltage & current are greatly reduced, still high, but since the duration is short, a good grounding system will dissipate quickly. Robert From: BVARC <[email protected]> On Behalf Of john Parmalee via BVARC From what the great video says, if you are comfortable working with 120V the simplest way to check out a ground rod is to see how much current it will draw and do the math. Don't attempt this without experience working with a live circuit. I have been told by licensed electricians that when a new service is turned up if there is the stub of a ground rod sticking out of the ground it is good. No testing required. The thing I don't know is where to get the ground rod to ground rod connections and the ground rods with the blunt ends so they can match the previously driven rod. Lowes only carries the 8 or it 10-foot rods and the coupling to the flex wire to the service box. I checked Amazon and found nothing. I am told the local rental yard will rent a hammer drill and the ground rod driving adapter. Another comment regarding the ability of a ground to carry a lightning strike. All bends of the ground wire should have the gentlest bends possible. A strike of lightning is a very fast rise time having many harmonics. We know this because we can hear lightning almost to the VHF bands, A bend will look like an inductor and raise the instant ohmic value of a ground rod. On the other hand, a few turns on a coax or power source lead will increase the ohms to you rig.it will not protect against a direct hit but might fend off some induced current from a nearby strike. In south Florida it is common to tie several knots in your modem phone line. In Michigan they wrap a phone line around a ¼” bolt , some washers and a nut.. In a message dated 5/23/2022 7:54:42 PM Central Standard Time, [email protected] writes:
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