[udayanmontreal]

Hi,
I am installing a small antenna for an HDTV and I want to be sure it is adequately grounded. My understanding is that it needs to be grounded to both a separate rod and to the main service ground; my main issues have to do with logistics and equipment.

First, the rod. At the hardware store, I was told that copper plumbing pipe is sufficient, but I'd like to be sure. I was only able to get a 3/4" pipe 4' into the ground - I realize that by NEC standards that is not sufficient, but will it do in practice? Whatever rod I use, grounding the antenna mast and the cable grounding block to it seem pretty clear.

Grounding the assembly to the main service ground is where I'm not clear. My understanding is that I should run a ground wire from the rod to the main service ground. The antenna and the service box are on opposite ends of the house, and the house is attached on both sides, so I cannot run this wire around the outside of the house. Is it safe to run it into the house and through the basement? What type of wire do I use, and does it need to be covered? If I am to attach it to the main service entry box, does it have to run into the box?

Thanks for your patience; I'm new to this.

[donf]

Why is that your: "Understanding"

Is that what the instructions call for?

[udayanmontreal]

Well, you see, that's just the point. Instructions about this tend to be a) rather generalized and b) sometimes contradictory, at least to someone who isn't fluent in electrical work. They also usually assume the optimum conditions such as full accessibility to any location in the house and the ability to drive a rod 8' into the ground anywhere. I realize that these are codes and have to be formulated along definite guidelines. That is why the questions came up. If I feel I'm falling short of the codes, I lack the experience to know how much improvising is safely acceptable. I have called an electrician to look over the situation and advise me, but I thought I'd also see if anyone out there has some practical experience with this. I don't mean to seem obtuse; I just want to be safe.
Thanks
Udayan

[donf]

Okay, you might want to consider reviewing Article 810 of the 2008 NEC.

There is a sticky at the top of this forum that tells you how to link to the code book.

In summary, there several critical steps to take.

1) Do not mount or connect the antenna mast in any way to the electrical service mast, if you have an overhead service drop.

2) You should have two devices, the antenna mast and a discharge block. Both have to be grounded and bonded to the electrical grounding system on the home.

The "Lead In" cable, cannot swing any closer than 2' exposed electrical power conductors.

The grounding of the mast must meet the standards of Article 810.21. In that article, it states that the grounding electrode must terminate to:

1) Grounding Electrode System (Article 250.50)

2) Interior Metal Piping system within 5' from it's point of entry (Article 250.52(A)(1).

3) Accessible Bonding Means (Article 250.94)

4) Metallic Service Raceway.

5) Service Entrance enclosure

6) Grounding electrode conductor or metal enclosure enclosing the grounding electrode conductor.

Also required is that the grounding cable from the mast to the grounding connecting be not longer that 20' and as straight as possible.

If you do sink a ground rod, it be copper and cannot be any less than 5' long.

Don't use aluminium wire for the grounding conductor as you cannot place aluminum any closer than 18" from earth.

The main purpose in grounding the antenna, mast and discharge unit is to protect from static discharges and lighting.

[udayanmontreal]

Thanks, I talked to the electrician and got good advice. But every bit helps.
Udayan