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Station Grounding

Oct 27th 2011, 19:56

NA9DS

Joined: Nov 19th 2001, 00:00
Total Topics: 0
Total Posts: 0
I am looking to improve my station and antenna grounds. I have been reading that I need to bond them all to the house electrical system ground. Does it matter if my house is grounded to a cold water pipe? My concern is if someone is in the shower and I take a lightening hit, can this cause a danger to the person in the shower? Also, my station and antenna are a significant distance from the main panel. The wire needed to go from the antenna mast to the house main panel would be about 75 feet. Looks like I would have to bring the bonding wire into my basement to connect to the water pipe at the same location as the electrical box.
Do I have any reasonable alternatives? I have found some great info. for this but not much on how to do it if your house is grounded to a water pipe and not a ground rod.
Thanks for any thoughts.
Doug
KC9AYS
Oct 27th 2011, 23:03

KG4MAV

Joined: Jan 11th 1999, 00:00
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Total Posts: 0
Well, this is from experience here, so I'll tell you how my electrician and I did this. I was working on rewiring this old house we bought a long while ago now. :) I went to find the ground rod and panicked when I couldn't find it. We had had the house upgraded to 200 amp from 60 am service a few years ago now. I found the ground, on a water pipe which is copper. However, the water pipe changed into PVC before it went out to the well. I called my EX-electrician and he wouldn't fix it so I got another one who happens to live about a half mile from me. He stated that it was against the code to do a ground like that any more. So we put a ground rod in outside and redid the house ground. (It also cured a lot of problems I had had.) So to answer you questions here. Put a ground rod in and call an electrician to put the ground wire out to it. Yes, you have to ground everything to the house ground. It is 175 feet from my tower to the house and I had to put in a ground rod every 8 feet to the house so it would pass the inspection. Then I got to bury it all about 6 inches under the dirt. By the way, there is 3 ground rods for the tower surrounded by a halo of copper which is in turn surrounded by another halo 8 feet out from the tower. Over kill? Maybe, but at least I don't have to worry about the static charges that build up. I also have Poly Phayser's on every coax and hard line coming into this place.
73
Russ Abbey
KG4MAV
Oct 28th 2011, 19:33

NA9DS

Joined: Nov 19th 2001, 00:00
Total Topics: 0
Total Posts: 0
I am starting to wonder if having an electrician put in a ground rod for the house and do away with the cold water pipe connection may be the way to go. Can't imagine what that will cost but we will see. I just was not comfortable with having a lightening ground attached to a water pipe that feeds showers etc. I may be a little paranoid but with static electricity being very unpredictable, I don't want to take any chances. Thanks for the input and I will see if anyone else chimes in.
Take care... 73
Jan 25th 2012, 22:07

KA0DKY

Joined: Aug 24th 2009, 08:18
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Total Posts: 0
Growing up as a kid I remember being warned never to use the telephone or the shower during a storm because of the hazard of lightning strikes. I still here the same warning on the Weather Channel. We had our electrical service panel upgraded to a 200 amp service and even though the house already had one ground rod the electrician said that due to the soil conditions we needed another ground rod. We live in hot sunny dry Arizona.
Jan 26th 2012, 03:46

WA0CBW

Joined: Apr 4th 1998, 00:00
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Total Posts: 0
You might want to re-think this. The basic premise of good grounding practices (and concurrence with the NEC) is single point grounding. The theory behind this is during a lightning event a surge voltage is induced and as it moves through your house you want EVERYTHING to go up to a bazillion volts together. Most lightning damage is caused by flash over. One piece of equipment is at a very high voltage while the piece next to it is at a different potential. A flash over then occurs between these objects causing the damage.

To prevent this you designate a single point for your ground system and connect all grounds to this point using home runs. All grounds including your copper pipe, radio equipment, large metal objects, tower, RF ground, etc. should connect to your designated single point ground (some kind of ground bus). Your single point ground bus should then connect to your external ground as well as the electrical ground. Don't forget that along with good grounding is the use of AC and RF surge suppression devices.

I spent 20 years installing commercial cellular and public safety sites. A good reference for grounding is the Motorola R-56 grounding and installation manual. The ARRL also has some good information on grounding. Remember that all of the grounding efforts are designed to reduce the likelihood of a lightning strike. NO amount of grounding will prevent damage from a direct lightning strike.

Bill - WA0CBW
ARRL Technical Coordinator - Kansas Section

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