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Old 21-Oct-2010, 12:10 AM   #6
GroundUrMast
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Join Date: Oct 2010
Location: Greater Seattle Area
Posts: 4,758
(Please note, I agree with your statement "Ground fault does not mean there is a faulty ground in electric circuits." However I am not referring to ground fault interrupters or faulty grounds. I have added a citation to my opening post that provides an explanation of the term as I am using it.)

John, I am sorry that you think I am trying to scare anyone. "The only recommendation I am making here is that you comply with the codes governing your lo-cal." I make the suggestion sincerely and in good faith.

In day to day operation, grounding will keep static charges from building up - that will reduce the possibility of electrostatic discharge damage to equipment. If that were the only thing to protect against, a light gauge grounding wire would be quite adequate.

If an energized conductor (a black wire for example) comes in contact with the antenna system (during a storm or failure of power pole due to some accident or even a faulty extension cord used near the antenna [Christmas lights for example]), then the current in the antenna system ground wire could be very high until the source of power is disconnected. The codes require relatively heavy gauge ground wire, apparently so the ground wire can carry enough current, long enough, to trip a breaker or blow a fuse. I presume that the code limits the distance an antenna ground wire may penetrate a building because, during an extreme fault condition (like the service drop wire in direct contact with the antenna system), even a 10 or 8 AWG wire could be heated to the point of failure (if that happens outside the building - bad, inside - really bad, a risk of fire in either case, but a strong reason not to run the antenna system ground inside the building if it can be avoided).

A direct hit by lighting is also an extreme situation were I would expect a code compliant installation to suffer significant damage. Still, I will sleep better if I know I have taken reasonable steps to reduce the possibility of equipment damage, electrical shock and/or fire.

Last edited by GroundUrMast; 11-Apr-2013 at 2:43 AM. Reason: Ponting out added citation re. definition of ground fault.
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