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View Full Version : Grounding the Off-Air Antenna??


somguy
07-13-08, 02:07 AM
I may be able to obtain an AM-21 and therefore re-connect my off-air antenna back which I used to use to get my hi-def locals. Can you tell me if the antenna is also required to be grounded or if I should just do so anyways to place it safe or is there no need? When it was first installed several years ago it was never grounded. Is there a need to do so? If there is, what would happen if one did not ground the antenna? Has anyone experienced any issues by not grounding it? Any input whatsoever is appreciated and thank you for reading my thread!!

RobertE
07-13-08, 08:14 AM
Follow the local code.

BattleZone
07-13-08, 09:39 AM
NEC requires grounding ALL antennas. Always has.

houskamp
07-13-08, 09:43 AM
run mine thru same ground block as sat lines..

gfrang
07-13-08, 10:59 AM
I am not giving advise but i have not and never will ground an antenna.I have had no trouble and have put antennas up since i was a kid.But if you do ground it do it right don't rely on just a grounding block ground the mast.

arxaw
07-13-08, 11:16 AM
To meet national and most local codes, an outdoor (not attic) antenna must be grounded and also connected to your main power ground. Same for sat dish.

Grounding may reduce your odds of a lightning strike, but it will not protect anything from a direct hit.

randyk47
07-13-08, 11:24 AM
Since mine is tucked away in the attic it's not a concern...at least I'm not concerned.

harsh
07-13-08, 11:44 AM
Grounding isn't just about lightning. It is also about draining off static charges created by air passing by. This includes air moved by the wind as well as fans.

2dogz
07-13-08, 02:06 PM
There are two parts to antenna grounding. Part one is grounding the mast to drain static. Part two is grounding the signal cable at the entrance to the house to prevent the cable from getting energized by AC power in event of fire, tornado, pole with power lines falls on your house or whatever.

Ever watched the show Engineering Disasters on the History Channel? Usually the result of not following accepted engineering practice. Think of the NEC as a collection of knowledge on the practical and safe methods of using electricity accumulated since it replaced gas lights over a century ago.

EricJRW
07-14-08, 10:55 AM
Since mine is tucked away in the attic it's not a concern...at least I'm not concerned.
+1!

babzog
07-14-08, 11:48 AM
There are two parts to antenna grounding. Part one is grounding the mast to drain static. Part two is grounding the signal cable at the entrance to the house to prevent the cable from getting energized by AC power in event of fire, tornado, pole with power lines falls on your house or whatever.


Interesting. What then, of buried electrical service? No overhead wires anywhere nr the house. If I ground the mast (tower), is grounding the cable at the house still necessary?

2dogz
07-14-08, 02:39 PM
Interesting. What then, of buried electrical service? No overhead wires anywhere nr the house. If I ground the mast (tower), is grounding the cable at the house still necessary?

Buried service doesn't change anything. All comm lines still need gounding at enterance of dwelling by code. And code is the law in most locales in the US.

Think fire. Think insulation melting and wires touching. Think electrocution and death. Think grounding.

babzog
07-14-08, 02:54 PM
Buried service doesn't change anything. All comm lines still need gounding at enterance of dwelling by code. And code is the law in most locales in the US.

Think fire. Think insulation melting and wires touching. Think electrocution and death. Think grounding.

Oh, I'm not saying I wouldn't comply (given that I know less than the experts, I have no problem overengineering a solution to be safe, compliant, etc). Just asking the Q to get a better understanding of the "why", is all.

If the original purpose of the code was to prevent electrifying the coax due to the potential of overhead wires coming down... and there are no overhead wires to come down, then what purpose, other than complying with ink on a page, does grounding those wires serve (since there is nothing that could electrify them)?