TooLate said:
RISC777,
Your quote raises some interesting questions about my own set up.
Got a good freestanding tower with the first section planted 4 ft into ground inside a 4ft cube of concrete. No sooner got it up and operating (SuperScanner CB Antenna for commuting purposes to work) than a June thunderboomer took out the SC, and a bunch of stuff in the house. Got all fixed or replaced, replaced SC with new SC and added a discone scanner on standoff 3/4 up the tower. All I had and could find and afford at the time was RoMex left over from a recent remodel for the additional grounding. Ran one full insulated (other than connection points) run of Rom. from each of the antennas to copper rods pounded into the ground outside the concrete base...all 3 wires per run are connected to a rod. Called the wrecker to hoist the 60+ft assembly back up and voilla (sp)...within a couple of months... another strike on the SC. This time it only knocked out one of the elements on the SC CB.
Called the electrician that we had wire the addition to the house and his as well as a couple of second opinions is that the tower is now grounded TOO WELL and has become an easy target...a lightening rod if you will.
We're in the MidWest in Tornado Alley so thunder and lightening are commonplace. Is there anything I can do now and from the ground (since it's a couple hundred $ for the wrecker each time (2) for a takedown and put up) that will help divert lightening? All we do now is leave the CB disconnected (don't use it anyway) and pull plugs etc on the scanner/ant at the first distant rumble.
Do you think it is the grounding setup or might it be that the SC model has an electric "selection box" both up on the antenna and in the house that is live with low voltage anytime the radio and antenna are on...could this be the "attraction" or was it truly the "over grounded" setup?
I've wondered this for over 10 years... All well read and experienced levels input is encouraged.
tl
First, I don't hold a Master ticket as an electrician. (That's why I stole another member's words before.
)
Lightning as I understand is the attraction of positive to negative, or negative to positive, whichever "direction" it goes. Lightning does go up. So there's a difference at ground, in earth, to what is in the air / atmosphere. Such as static electricity in your house, like, when you're in your socks, it's going to "go somewhere."
Did the electrician or the other second opinions look at if the mast's ground is tied to the house's electric service neutral bus?
How many total rods are connected to the mast, and how long / deep are they? (Three rods?)
One thing I do differently, be it by code or not, is I ground my masts, versus running the ground line(s) to antenna(s). Anything attached to the masts are grounded. All masts are connected, the ground run goes to an 8' rod with #6 bare solid copper and is connected to the buildings service ground.
To answer what you can do from the ground is get some #6 copper and ground the mast (to the ground rods). If in fact you've created or ended up with a lightning rod, doing that won't make the problem worse. But by doing that you've got a larger path for any future lightning strikes to get to earth ground.
To get an answer to the question, "Is it grounded too well?" That's out of my scope. It's possible that it's an attractor now, a lightning rod in effect. My own thought if it were my situation would be - do I invest in setting up a true lightning rod that would be designed to "attract" lightning more than my mast?
Lightning is lightning. I've seen it blow a driveway up, run into the house on TV coax and phone line, run out a power line to a shed and blow it up, but damaged nothing internal to the house (other than the two crisped wires).
*maybe kb2vxa or someone else with more knowledge and experience will respond also*
