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-   -   How would you ground in this setup? (pics included) (http://forum.tvfool.com/showthread.php?t=14680)

billydee 25-Jul-2014 3:59 PM

How would you ground in this setup? (pics included)
 
8 Attachment(s)
So a couple weeks back we rigged up a mast using two 10ft sections of 2 inch threaded EMT conduit. This might be a bit of overkill so I may switch it out to 1 1/4 or 1 1/2 inch. Then we set an HDB8X antenna up and am getting all the channels I'm supposed to.

Now we need to ground it properly. There's quite a bit of lightning certain times of year here in SW Colorado so I'm concerned and want to get it right.

As you can see from the pictures the mast is about 10 feet away from the roof of the house and is secured onto a 4x6 vertical wooden beam which is part of the decks roof. This is somewhat temporary for now until I make a final decision on which size conduit to use but the mast location where you see it is pretty much final. I used this location as it has the cable running into the house already there from a previous dish installation and I wouldn't need to deal with mounting on the roof.

For grounding I'm assuming an 8ft connected copper rod beat into the ground directly under and next to the mast will be adequate? That said I'm still a little unclear about what the grounding will actually look like (wires, clamps etc...) so that's why I'm asking for help. I want to keep my cost to a minimum but not scrimp on safety.

Thanks in advance for your advice/thoughts. :)

ADTech 25-Jul-2014 8:41 PM

How far is your new mast from the main electrical service entry to the home?

billydee 25-Jul-2014 8:48 PM

Quote:

Originally Posted by ADTech (Post 45140)
How far is your new mast from the main electrical service entry to the home?

Great question, I'll need to measure it and get back to you.
And just to clarify you don't mean the location of the electrical panel but where the main from the road meets the house (which I know is underground)?

ADTech 26-Jul-2014 1:45 AM

Under your servicemeter base should be a heavy ground wire (typical home ground) that disappears into the ground, presumably to ground rods that are out of view under the ground. your ultimate requirement is to have one combined ground, all bonded together. The distance from your mast is too great (check if local codes apply), then you'll need a separate ground rod that is also bonded to the main ground. If the mast is close enough, you can run the mast and coax grounds directly to the main ground and dispense with the additional ground rod. This should be considered the minimum grounding exercise, you're always welcome to exceed the minimum.

Grey Hair 74 20-Jan-2015 12:16 AM

What gauge is common for ground.. solid or stranded ? And grounding for coax ?

GroundUrMast 20-Jan-2015 1:10 AM

Article 810 or the NEC calls for #10 AWG copper as the smallest diameter conductor to be used to connect the mast to your existing electrical service ground. The connection between your coax grounding block and electrical service ground is a separate connection and is also to be at least #10 AWG copper. (The NEC does provide for some alternates to copper, but copper is going to be corrosion resistant and easier to obtain for most folks.)

The conductor can be solid or stranded, insulated or bare.

If you add a ground rod, the minimum conductor for bonding it to your existing electrical service ground system is #6AWG (which is larger in diameter than #10).

Connections to ground rods should be done with a connector that is rated for 'Direct Burial'. These are usually bronze, very corrosion resistant, and have strength similar to many grades of steel. The big box home centers are usually stocked with such parts and materials.

See: http://forum.tvfool.com/showthread.php?t=901 (post #20 is a summary)

Grey Hair 74 20-Jan-2015 4:43 AM

Thanks...for the information ... is the ground block for coax a fusible link..? is that ground block placed at the antenna mast.. or any were with in the run of coax ?

GroundUrMast 20-Jan-2015 8:33 AM

Here is an example of a common coax grounding block: http://www.amazon.com/F-pin-Coaxial-.../dp/B001I5610E It does not contain any fuse. It simply provides a reliable connection to the outer shield of the coax so that it can be solidly connected (bonded) to an appropriate protective ground point such as the electrical service grounding rod.

The ideal location for a ground block is near the electrical service ground rod (or equivalent if your electrical service uses another method to connect to earth) such that no more than 10' of wire is needed to make the connection between the ground block and electrical service ground. Also, it's best practice to run the coax from the antenna to the ground block without penetrating the structure (keep it outside) until it passes through the ground block, then it can enter the structure. This directs fault current that is from an outside source to stay outside the structure.

There are premium options, for example: http://www.amazon.com/TII-Broadband-...ywords=tii+212 In addition to a solid connection to the shield, this type of protector does include over voltage protection for the center conductor of the coax.

Grey Hair 74 20-Jan-2015 5:40 PM

Quote:

Originally Posted by GroundUrMast (Post 48869)
Here is an example of a common coax grounding block: http://www.amazon.com/F-pin-Coaxial-.../dp/B001I5610E It does not contain any fuse. It simply provides a reliable connection to the outer shield of the coax so that it can be solidly connected (bonded) to an appropriate protective ground point such as the electrical service grounding rod.

The ideal location for a ground block is near the electrical service ground rod (or equivalent if your electrical service uses another method to connect to earth) such that no more than 10' of wire is needed to make the connection between the ground block and electrical service ground. Also, it's best practice to run the coax from the antenna to the ground block without penetrating the structure (keep it outside) until it passes through the ground block, then it can enter the structure. This directs fault current that is from an outside source to stay outside the structure.

There are premium options, for example: http://www.amazon.com/TII-Broadband-...ywords=tii+212 In addition to a solid connection to the shield, this type of protector does include over voltage protection for the center conductor of the coax.

Thanks... I was not sure if the ground blocked just melted after a strike or not.. good information


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