View Full Version : Grounding & Mounting questions
gossamer
20-Jun-2011, 4:53 PM
Hi all,
I've identified the antenna I'd like to purchase, and would like to mount it using a Y wall-mount bracket, like this:
http://www.3starinc.com/ez30-24_deluxe_y_wall_mount_antenna_bracket_24_inch_.html
Whether I use a 5' or 10' mast, there will still be interference because of trees. Should I instead choose just a 5' because it will be less likely to be impacted by the wind, or doesn't it make a difference either way? I plan to use the 18 gauge galvanized masts for this:
http://www.3starinc.com/ez5-16_galvanized_antenna_mast_5_foot_by_1_25_inch_od_16_awg.html
Grounding in my house is done by connecting the electric service to the main water line inside the house with a regular water pipe ground clamp. To ground the antenna, am I supposed to run a ground wire from the antenna mast into the house and connect it using a ground clamp on the water pipe?
Or is it sufficient (or correct) to use a coax ground block once the wire is inside the house, like this?
http://www.3starinc.com/holland_grb-1_single_ground_block.html
The cable would come into the house with the rest of the cable wires, where the water service is also located.
Sure appreciate any ideas.
Thanks,
Dave
GroundUrMast
20-Jun-2011, 5:28 PM
http://forum.tvfool.com/showthread.php?t=901
If you are interested in what the NEC calls for, it allows you to bring the grounding conductors for an antenna system into the building as far as five feet. That is an allowance for situations such as yours, where there is no ground rod outside the building.
Ideally, you would run a #10 or larger copper wire from the mast, to the electrical service ground... in as direct a path as possible, avoiding sharp bends. All outside the building.
Ideally, you would run the antenna lead/coax to a block such as the one you linked to. That block would be located as close to the electrical service ground as is practical. The ground block would be connected to the electrical service ground with a #14 or larger copper wire, as directly as possible and with no sharp bends. All outside the building.
Best practice would keep the mast and coax ground separate until they come together at the electrical service ground.
You can add a ground rod... if you choose to, it must be bonded to the existing electrical service ground with a #6 or larger copper wire. I chose to do this because my mast is some distance from my electrical service.
A beer or two invested in a local electrician friend may pay dividends... in advise or help.
gossamer
20-Jun-2011, 5:52 PM
http://forum.tvfool.com/showthread.php?t=901
If you are interested in what the NEC calls for, it allows you to bring the grounding conductors for an antenna system into the building as far as five feet. That is an allowance for situations such as yours, where there is no ground rod outside the building.
Ideally, you would run a #10 or larger copper wire from the mast, to the electrical service ground... in as direct a path as possible, avoiding sharp bends. All outside the building.
The electric service and the water meter are within two feet of each other in the house. I believe the electrical service ground is simply a copper wire from the electric service to the main water pipe. There is no grounding rod outside, as far as I can tell.
Ideally, you would run the antenna lead/coax to a block such as the one you linked to. That block would be located as close to the electrical service ground as is practical. The ground block would be connected to the electrical service ground with a #14 or larger copper wire, as directly as possible and with no sharp bends. All outside the building.
Okay, so in my case, where there is no external ground, the coax would be grounded inside using one copper wire, and the antenna would be grounded with a wire from the roof, into the house, and terminated as well at the water main, correct?
What kind of connector do I need to provide ground at the antenna itself? Perhaps it's already supplied with the eave mounting kit?
Best practice would keep the mast and coax ground separate until they come together at the electrical service ground.
Basically you're saying that there should be a ground run for the antenna as well as the coax terminated inside, correct?
You can add a ground rod... if you choose to, it must be bonded to the existing electrical service ground with a #6 or larger copper wire. I chose to do this because my mast is some distance from my electrical service.
A beer or two invested in a local electrician friend may pay dividends... in advise or help.
I can get in contact with someone who has the tools to drive the grounding rod into the ground, but that would probably be a long process and have other difficulties. The electrician that upgraded our service some time ago is a great guy, but I'm sure a service call to the house to evaluate our existing system again would be necessary...
Don't imply that I'm trying to cut corners; I'd just like to better understand the imperatives.
Too bad you weren't in the NYC area; I'd like to buy you a beer :-)
Thanks again,
Dave
GroundUrMast
20-Jun-2011, 10:54 PM
The electric service and the water meter are within two feet of each other in the house. I believe the electrical service ground is simply a copper wire from the electric service to the main water pipe. There is no grounding rod outside, as far as I can tell.Which makes one consider verifying that the water service line is metallic and does not have insulating connectors.
Okay, so in my case, where there is no external ground, the coax would be grounded inside using one copper wire, and the antenna would be grounded with a wire from the roof, into the house, and terminated as well at the water main, correct? Correct, unless you elect to add a ground rod outside, bonded to the ground point inside the house.
What kind of connector do I need to provide ground at the antenna itself? Perhaps it's already supplied with the eave mounting kit?The big box home centers stock ground clamps... Ex. Home Depot bronze clamp (http://www.homedepot.com/Electrical-Electrical-Boxes-Conduit-Fittings-Conduit-Fittings/h_d1/N-5yc1vZbohk/R-100149923/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053) or, same or similar at 3starinc (http://www.3starinc.com/tower_base_copper_ground_clamp.html)
Basically you're saying that there should be a ground run for the antenna as well as the coax terminated inside, correct? I'm saying that there should be two connections to the electrical service ground. 1 - The mast ground (which will include the antenna boom and mounting hardware). 2 - The coax ground block (most matching transformers will insulate the coax from the antenna elements from DC up to about 5 MHz). The two connections complement one another and ideally do not merge anywhere but the electrical service ground.
vBulletin® v3.8.11, Copyright ©2000-2025, vBulletin Solutions Inc.