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Author Topic: lightning protection  (Read 8177 times)
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WA1GFZ
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« on: June 27, 2005, 11:48:57 AM »

I had an eyeball with my building inspector and he suggested I run a ground lead from the breaker panel to the water main on both sides of the water meter. I brought him over to the meter and showed him the handful of #8 wires coming through the wall with the main and told him I suffered from ham radio disease. He had a number of radio stories where
rigs were between grounds and got fried. He told me to make sure the antenna system ground system didn't get power ground through the rig chassis. The key is a heavy ground connction back to the breaker panel ground to avoid offset voltages. 200 amp service requires #4 solid copper
to 2 ground rods at least 5 feet apart.
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Pete, WA2CWA
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« Reply #1 on: June 27, 2005, 12:44:49 PM »

Quote from: WA1GFZ
I had an eyeball with my building inspector and he suggested I run a ground lead from the breaker panel to the water main on both sides of the water meter. I brought him over to the meter and showed him the handful of #8 wires coming through the wall with the main and told him I suffered from ham radio disease. He had a number of radio stories where
rigs were between grounds and got fried. He told me to make sure the antenna system ground system didn't get power ground through the rig chassis. The key is a heavy ground connction back to the breaker panel ground to avoid offset voltages. 200 amp service requires #4 solid copper
to 2 ground rods at least 5 feet apart.



When I had 200 amp service put in several years ago (house had only 100 amp service), the chief electrician/owner, who is also ham, also did the same thing.  He also used #4 solid copper wire from the main to both sides of the water meter. Also added a #4 jumper between the hot and cold water pipes of the water heater. He also added a clamp from the main side, with some extra #4 wire to connect to my ground system at the equipment.
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Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
WA1GFZ
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« Reply #2 on: June 27, 2005, 12:51:38 PM »

Pete,
The antenna tuner will sit near the breaker panel so that should take care of loops. I was surprised by the building inspector being so sharp.
I heard he was a pain but disagree, he is actually very helpful. fc
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w3jn
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« Reply #3 on: June 27, 2005, 01:12:00 PM »

That's in the NEC.   All auxiliary grounds must be bonded to the service entrance ground.  I.E., they must have a dedicated wire run to them.

You can have a considerable voltage potential between the service entrance ground and your station ground, especially in the presence of lightning, if this isn't done.

73 John
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Pete, WA2CWA
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« Reply #4 on: June 27, 2005, 01:32:18 PM »

I just went down to the basement to check the size of the ground wire from the breaker box to the water meter and it's #2. The run from the breaker box to the water meter is about 35 to 40 feet. The wire from the clamp on this wire to the equipment is also #2. However, when lightening comes, I always disconnect all the coax cables and rotor cables and drop them on the basement floor. When severe summer storms come along, I also disconnect the AC mains from the operating area.
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Pete, WA2CWA - "A Cluttered Desk is a Sign of Genius"
WA1GFZ
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« Reply #5 on: June 27, 2005, 01:39:45 PM »

The antenna tuner is the place to generate a loop since the tuner needs a good RF ground and safety ground. I suppose the tuner should get both.
Then the shack gets both so it will be a trick to avoid an offset. I'm putting the tuner near the panel to avoid a big loop. Another problem is coax into the rig. I suppose one should run a safety ground off the shield back to the single point ground so it isn't made through the chassis.
I disconnect everything when out of the shack
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K1JJ
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« Reply #6 on: June 27, 2005, 02:00:28 PM »

Good subject for the summer storms!

I went thru the trouble of running an underground #6 wire
from the power line pole ground [at the street pole]
back to the underground cable that runs up to the towers and
ties into their ground systems. Also tied in the telephone line
ground to this same cable at the telephone entrance to the
house as well as the cable TV ground.  All cad welded.

And finally a ground wire comes out of the shack and taps to this
system.  Like Frank, it has an alligator clamp that I disconnect
with antennas during T-storms.

In the past I lost lots of hardware - telephones, computer cards,
etc. due to lightning. Nothing damaged since this ground installation
back in '98.

T
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Todd, KA1KAQ
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« Reply #7 on: June 27, 2005, 02:01:09 PM »

I always enjoy reading these grounding posts because I always learn more. Separating the myths from the actual facts can be confusing, though. Latest thing I read for station equipment said not to ground each piece individually, instead run them all to the tuner as a common point and ground the tuner. But what if you have multiple stations and tuners? Run each station's associated equipment to its tuner and ground it separately from the others, to the same common (entrance?) ground?

And if you're doing it this way, how do you keep the equipment grounds from running into the antenna ground? Wouldn't hooking all of your equipment to the tuner immediately put you into the antenna ground path?

*scratches noggin... :?
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Steve - WB3HUZ
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« Reply #8 on: June 28, 2005, 12:45:50 AM »

Read, learn, do.


Grounding for Amateur Radio Stations by Bob, K4TAX
http://www.amwindow.org/tech/htm/grounding.htm

Lightning Protection by Bob, K4TAX
http://www.amwindow.org/tech/htm/lightning.htm
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Tom W2ILA
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« Reply #9 on: July 01, 2005, 05:21:05 PM »

I have been using Polyphaser stuff at work and they have a decent website with tutorial papers in the technical info section.
Here is one on ham radio grounding:   http://www.polyphaser.com/ppc_TD1016.aspx  

73
Tom W2ILA
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