Grounding an antenna

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VE2XWA

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Asking for friend, really!!

The power meter and the electrical panel are connected to the main water pipe. His antenna support is connected to the same ground wire going from the meter to the main water pipe. He want to move his antenna at the opposite of the house. At that place there’s an external water pipe, copper one of course. Will it be ok to connect the antenna support to that water pipe since reaching the power meter or the electrical panel is out of question.



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VE2XWA

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It would be best to run a separate 9' or 12' copper rod in the ground closest to the antenna.

Yes that will be done too. Sorry should have said that too. But everything needs to be bonded together right?


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KB4MSZ

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I would suggest a separate ground system as Jacob mentioned above. Having an antenna grounded to a path that leads into (and throughout) a home is really not the best practice, especially in the case of lightning. Living in Tampa will teach you that for sure. Rigid copper refrigeration tubing makes a really good ground rod. The 1/2" size can slide into a hose and be water jetted into the ground. A 10 foot length is easy to sink. Wrap the ground strap (preferably copper) tightly around the pre-tinned copper tube and torch it with solder. The tower or mast side will need cleaning and re-attaching from time to time as the metals will react to each other.
 

prcguy

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One thing that causes extra damage in a lightning strike is an antenna system that is grounded separate from the house ground. Equipment that might otherwise survive can be killed off by huge differences in potential between grounds when you don't bond them together. If the lightning strike can be mitigated between hot and neutral, many thousands of volts can still be generated between the coax shield connected to the antenna grounded far away and the radio grounded at the house. This can affect everything plugged into AC power inside the home.

Look up NEC article 810 for grounding antennas for guidance.

I would suggest a separate ground system as Jacob mentioned above. Having an antenna grounded to a path that leads into (and throughout) a home is really not the best practice, especially in the case of lightning. Living in Tampa will teach you that for sure. Rigid copper refrigeration tubing makes a really good ground rod. The 1/2" size can slide into a hose and be water jetted into the ground. A 10 foot length is easy to sink. Wrap the ground strap (preferably copper) tightly around the pre-tinned copper tube and torch it with solder. The tower or mast side will need cleaning and re-attaching from time to time as the metals will react to each other.
 

VE2XWA

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One thing that causes extra damage in a lightning strike is an antenna system that is grounded separate from the house ground. Equipment that might otherwise survive can be killed off by huge differences in potential between grounds when you don't bond them together. If the lightning strike can be mitigated between hot and neutral, many thousands of volts can still be generated between the coax shield connected to the antenna grounded far away and the radio grounded at the house. This can affect everything plugged into AC power inside the home.

Look up NEC article 810 for grounding antennas for guidance.

So what would you suggest? Water pipe or a large buried cable? Like 75’


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prcguy

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I can't suggest anything to survive a direct hit except for a professional to design a system specific for your location. Its difficult and expensive to retrofit an existing house and antenna system to survive a direct hit. If someone was building a new house it would be easier but still expensive.

I think its much worse to do grounding and install lightning protectors yourself and assume you are protected from a direct hit, which you are not.


So what would you suggest? Water pipe or a large buried cable? Like 75’


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rja1

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One thing that causes extra damage in a lightning strike is an antenna system that is grounded separate from the house ground. Equipment that might otherwise survive can be killed off by huge differences in potential between grounds when you don't bond them together.

Absolutely 100% correct! You MUST bond all grounds together. Think of the earth as a big resistor......The potential difference between two grounds, say 30 feet apart, can rise to TENS of thousands of volts, or more. You want everything to rise & fall AT THE SAME TIME.

Bob
 
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W5lz

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Think about it... all electrical grounding is, or should be tied together. That's per NEC.
 

trx680

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So this IS a tower that is NOT connected to the house? It is in the yard itself?

I'm researching what it takes to properly ground a tower that would be in my back yard. A short tower..20' or so. It will just be an antenna on the tower, no antenna motor. So the only thing connecting the tower to the house is coax.

Could I ground the tower and the coax at the base of the tower? Or would I still have to tie in to the main ground rod thats at my meter?
 

trx680

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All ground rods should be tied together.
Just thought of something.
I have DirecTV. The installer mounted a dish in my yard on the opposite end of the house from the meter.
He ran the coax under the house and up to the TVs. I don't have home phone so he didn't tap into my phone system.
I don't recall him grounding anything.
This is an antenna. Should it have been grounded by code?
 

mmckenna

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This is an antenna. Should it have been grounded by code?

Yes. Some satellite TV installers are sloppy and will do the least amount of work possible.

I'm researching what it takes to properly ground a tower that would be in my back yard. A short tower..20' or so. It will just be an antenna on the tower, no antenna motor. So the only thing connecting the tower to the house is coax.

Could I ground the tower and the coax at the base of the tower? Or would I still have to tie in to the main ground rod thats at my meter?

Your tower needs to be grounded at the base to at least one ground rod, maybe more depending on soil conductivity.
That ground rod should also be bonded to the house electrical entrance ground rod.
Your coaxial cable should be grounded to the tower at the top and then again at the base.
Where your coaxial cable enters your home, you should have a lightning protector that is grounded to a ground rod that is also bonded to your house ground.

Things like soil conductivity, ground conductor size, rod length, number of rods, etc. are things that should be properly designed by a qualified person. National Electric Code requires the grounding that I mentioned above. If you chose not to follow the NEC, that's your choice, but understand that electric codes exist for a good reason.
 

prcguy

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When a DIrecTV installer first goes on your roof he is looking for two things, a good path to the satellites and a ground wire run to your electrical panel not to exceed about 30ft. If either of those cannot be met he is not supposed to do the install. I was a certified trainer for DirecTV installers so I'm a little familiar with this.

Just thought of something.
I have DirecTV. The installer mounted a dish in my yard on the opposite end of the house from the meter.
He ran the coax under the house and up to the TVs. I don't have home phone so he didn't tap into my phone system.
I don't recall him grounding anything.
This is an antenna. Should it have been grounded by code?
 
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