These posts on lightning protection served to get me considering my shack, etc. I had solar panels installed last summer, and on the side of the house opposite the electrical entrance panel the installers ran a wire from the PV panels, inverters, etc., down to a ground rod they put in. So I asked them yesterday if there was any bonding of that rod to the ground on the entrance panel side of the house. The response was "They are not bonded. That ground rod is not a system ground and does not need to be bonded to the existing grounding system. It is purely for lightning protection."
--Dave, W8OV On 3/29/2011 8:23 AM, Don Wilhelm wrote: > Phil, > > Despite disconnecting your antennas, you still have to consider that the > coax shields enter the house. > > Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC > Electrical Entry ground rod. > > I am not sure why that is counterintuitive to you. Yes, there is a very > real possibility that a lightning surge will be induced in the house > wiring with or without the connection between the grounds. But if there > is a lightning surge on either the antennas or the house wiring, you > want to keep both at the same potential. > > Keeping everything at the same potential during a lightning surge event > is what the bonding is all about. > > A lightning surge traveling through the earth can create a very large > difference in potential between ground rods that are not connected > together, and that potential difference can cause fires and damage. The > soil has more resistance than a wire between the ground rods. > > Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact > that ALL ground rods should be connected together is clearly stated. > > One other point on disconnecting your antennas - consider what happens > when you re-connect them. The PL-259 center conductor is connected > first, and then the shell is attached. If there is a charge on the coax > center conductor, you can zap your equipment by the simple act of > re-connecting it. Short the center conductor to the grounded shell > before connecting it to your equipment. It is better to disconnect the > antennas with a switch in the coax line and provide a DC path to ground > across the common coax connector at that switch. > > 73, > Don W3FPR > > On 3/29/2011 1:12 AM, Phil Townsend wrote: >> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the >> outside coax switch >> and have installed a Poly Phasor on the output coax that goes into the shack >> and poly phasors on each of the coax cables from the antennas. >> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly >> phasor has its own wire going to ground rod #2) >> >> This remote coax switch and ground rod #2 are about 12 feet from the AC >> mains. >> >> If I understand correctly, I should also bond this ground rod #2 to the the >> AC mains ground rod as well???? >> >> But if I do that then those antennas will be connected to the grounds in the >> house via the AC mains ground rod????? >> This seems counterintuitive? I mean... now there will be the very real >> possibility of lightning in the house wiring??? >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
