Antenna Grounding - How to?
I want to install outdoor antenna (about 7 feet above the eaves or about 2 feet above the roof line). I have questions on the grounding, especially for the mast. I found that in NEC 810.21(F) (1), one of the places where the grounding conductor must terminate to is "Service equipment enclosure".
My questions are:
1. Does it mean that I can use the ground clamp (a small clamp attached to the panel/enclosure) on the service meter panel/enclosure (outside the house) to ground both the mast and the coax, with NO need for extra/separate grounding electrodes (grounding rod or plate)?
2. I am thinking of running the grounding conductor (AWG 8) from the mast to a grounding plate (2 feet below surface), then for the coax, I will use a grounding block, then run a AWG 10 from the block to the grounding plate. Now, I need to bond the plate to the house grounding with AWG 6. Again, the question is: can I bond the grounding plate to the ground clamp on the service meter panel/enclosure at the outside of the house? or should I bond it to the in-house electrical panel/enclosure (it's just on the other side of the wall of where the service meter panel is)?
- kg7orLv 71 decade agoFavorite Answer
Your question is marked as coming from Canada, which is governed by the CEC rather than the NEC. So I'm not sure if you really need to ground the mast to the service panel enclosure. From a practical standpoint, your suggestion about using a buried grounding plate is thoroughly adequate. I've erected several antennas with the ground cable soldered to a 6-foot copper-coated rod driven into the soil alongside the foundation, and that was fine. (If you do that, be very aware of what's underground beneath the rod.)
The point of attaching to the service panel cabinet is to get the connection to actual earth ground, which the grounding busbar in the cabinet provides. But you've done the same thing with a buried grounding plate or ground rod. If your mast is hit by lightning, the lightning will be just as happy with either grounding method. So I'd go with the buried plate or ground rod.
As you suggest, a lightning arrester in the downlead is also highly recommended if you're in an area susceptible to lightning strikes.