Grounding a satellite dish

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Direct TV is coming out next Thursday to install a dish. I told them they could ground it properly or I would not subscribe. Here is an image I am going to send them tonight so the truck guy will know what to expect when he gets here.
Clear enough to follow?
http://i35.tinypic.com/2n031vk.jpg
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So uhhhhhh... Hallerb. What haven't you done? :-)

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I was a dish dealer for awhile and even attended as a VIP the launch of echostar 6. satellite tv has been a interest for over 12 years although i am not nearly into it as i once was.
I run my own office machine service business since 1984 when my former employeer went belly up. I have a wide variety of interests and the older you get the more info you pick up along the way
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On Wed, 3 Dec 2008 19:58:58 -0800 (PST), " snipped-for-privacy@aol.com"

What would be your estimate of how many satellite dishes are installed according to the NEC?
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Well below 50%. Your diagram has some problems as snipped-for-privacy@aol.com has noted. Coax entering a building must connect short to building ground 'before' entering the building - a less than 10 foot connection. Split bolt connection is best made as close to the earthing electrode as practical. A ground wire across an attic accomplishes little for all that work and cost.
Antenna must be earthed. Cable must be earthed where it enter the building. Code goes even farther - demands that dish earth ground connect to AC mains ground. In your case, best done with a buried bare copper wire (per code) routed underground. That buried wire enhances both earth grounds as well as meets code. Even many better installations don't bother.
However, at minimum, an entering coax uses a ground block to connect short to AC electric earth ground - routed so that the grounding wires remain separated from all other wires.
This earth requirement is one reason why dishes are often located nearby the AC electric meter. Of course, the disk must have a widely clear view of the satellite - ie trees can grow and still not obstruct the view ten years later.
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My point is the OP wanted to do it right, while his diagram is wrong.
as far as I know few dishes are grounded directly themselves, installers use the grounding block at home entrance, it appears to work fine.
grounding the dish might make it more attractive to lightning.'
plus low to the ground if you have line of site is far better than on roof
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Grounding a dish is required by NEC. It does not attract lightning. Lightning seeks a connection into earth. If the majority of lightning current conducts on that required ground, then less threatens dish electronics or the receiver. Grounding a dish is part of a system required so that direct lightning strikes cause no damage.
Having direct strikes to antenna systems without damage is routine. How the 'system' is earthed determines whether damage will occur.
Meanwhile, that cable must also be grounded to AC electric earth ground also for another reason - human safety.
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On Thu, 4 Dec 2008 16:52:12 -0800 (PST), snipped-for-privacy@gmail.com wrote:

Bonded is the better word, but thanks.
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On Dec 4, 7:52�pm, snipped-for-privacy@gmail.com wrote:

if lightning hits a dish that dish will be history.
lightning does strike antennas, and wiped channel 4 WTAE ofdf the air one time for over a day
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Those are the popular myths. Some see a rare exception, then assume that exception is the rule. Instead, we learn from experience and consult experts. For example, well over 95% of all lightning struck trees have no appreciable indication. Lightning is not the massive destroyer often promoted in myths. Properly earthing a dish mean no damage - just like earthing a lightning rod. Routine is to have antennas struck by lightning without damage. Antennas atop the Empire State Building suffer about 25 direct strike per year without all that damage.
Well, some station engineers out of ignorance compromise the earthing system. How routine is lightning with no damage? http://www.harvardrepeater.org/news/lightning.html

Low impedance is why a connection from coax ground block to building earth ground at the service entrance must be short - ie less than 10 feet. So that energy from a lightning strike to the dish does not cause building damage, that dish is earthed just like Ben Franklin did in 1752 to eliminate church steeple damage. Routine is to have direct lightning strikes with no appreciable damage.
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On Wed, 3 Dec 2008 13:51:03 -0800 (PST), " snipped-for-privacy@aol.com"

The wire in the attic is a bonding wire, not the ground line. A lightning strike should go to ground directly beneath the dish. That is why I bought the extra ground rod.

BTW I didn't mention in the original post that there has been one of each, Dish and Direct, already mounted in that spot. I originally bought a chimney bracket extra, and neither company has bonded it properly. It did have a very small ground rod there, but was never bonded to the house.
3rd time is a charm (I hope)
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i would run the bonding wire outside. no advantage to running a possibly energized linew inside your home.
get your chimney inspected yearly, by climbing up and looking down on the chimney cap.
your far better off having it low. is high up a security issue or the idea antennas always go on chimneys? a left over from days when everyone had a antenna on their home. chimney was highest spot, old antennas were thin spindly metal with near zero wind resistance
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snipped-for-privacy@aol.com wrote:

I remember having to drag the hose out of the cellar and blowing the snow off the dish with water so I could receive a signal. That wet sticky snow is a pain in the ass. I do not like climbing on a 2nd story roof full of snow. They had bolted it to the roof, I questioned about a leaky roof with lag screws into the shingles. I had 3 chimneys. It didn't leak though. He put rubbers between the mounting brackets and roof. I don't remember any grounds.
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metspitzer wrote:

You really need to let an expert handle this:
* The purpose of grounding a satellite TV dish is to dissipate static electricity generated by the dish being exposed to the wind. The shorter the run, the better the static drain-off will be. Excessive static electricity will interfere with reception. If you're mistakenly thinking there's some sort lightning protection via the ground, you're wrong. All lightning arrestors have a pointy end in order to work. There's nothing pointed about a satellite dish.
Ninety feet is ten times too much.
* The best place to mount a satellite dish is on a pole stuck in a pot of concrete or attached to a deck railing. The higher you mount the dish, the worse off you'll be. (Because you can't easily adjust the dish or remove the snow.)
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Something to think about: if you ground the sheath of the cable AND the dish to a common ground, you may find that you have "ground loop" noise in the sound and picture of your TV and/or receiver. While the dish should be grounded independently, you may have to isolate the grounding of the cable sheath so that it is only grounded at the TV and/or receiver. I tend to use a cable with an additional ground/carrier wire molded together.

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EXT wrote:

As several people have said, the NEC *requires* the dish cable sheath to be grounded at building entry to the same earthing electrode system as used by the power system (and cable and telephone).
While there is a maximum length for the interconnecting ground wire for cable and telephone, there isnt for dish. A likely reason is there is significant chance of surges produced by lightning coming in on cable and phone wires. A short wire is critical to minimizing the voltage between power and phone or cable wires. But if lightning hits your dish you are (to use the technical phrase) in deep doo doo. A short wire is, however, a good idea.
-------------------------- Cable systems have the cable entry earthed at each building. There has to be significant difference in potential between some buildings which should result in ground currents and ground loops in the shields. Why isnt that a problem for cable? (My guess is a high pass filter.)
--
bud--

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ALL GROUNDS MUST BE UNIFIED THAT IS CONNECTED TOGETHER FOR SAFETY. As long as they are unified, no ground loops can occur
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