New Install: how long can the ground wire be

T

Tony S

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R-U-Q-R-U said:
Also, is correct that if I do NOT have a lighting arrest system they should NOT ground the dish, just the coax?Thanks.
Yes, that is true. Just ground the coax. The ground is there to dissipate static electricity build up.
 
SimpleSimon

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Tony S said:
Yes, that is true. Just ground the coax. The ground is there to dissipate static electricity build up.
Sorry, you're wrong. Both the Dish AND the LNBFs MUST be grounded. They are eleectrically isolated from each other due to the plastic "Y" arm.

If you don't do it, you risk a static build-up across the two that can discharge into the LNBF, frying it.

It has NOTHING to do with any lightning "arrest" system, which I can only assume is a static discharge setup (lightning rods).

As for grounding to the A/C breaker box - that depends. Can't say without seeing it -other than if the box's ground wire goxes to a GFCI breaker in the main box, it can NOT be used.
 
T

Tony S

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The information that I provided was originally given by Dan Collins (at DBSForums) in answer to questions that were asked in his forum. Dan is an expert in this field and I would give great credibility to what he advises. He advised not to ground the dish unless it was part of an overall whole house lightning protection system, especially if the dish was placed on a roof.
 
Foxbat

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It amazes me how often a well-regulated subject like this comes up and causes no end of arguements. Every piece of consumer electronics that could be connected to an external antenna comes with a reference to the NEC Article 820-40 Guidelines for proper grounding and includes a diagram like the one I've attached, which clearly shows that the antenna needs to be grounded as well as the coaxial cable(s) from the antenna at the point where they enter the premises.

Of course, there may be local, state, or federal requirements that supercede the NEC, but your installer should be well aware of those.
 

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R

R-U-Q-R-U

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Foxbat said:
It amazes me how often a well-regulated subject like this comes up and causes no end of arguements. Every piece of consumer electronics that could be connected to an external antenna comes with a reference to the NEC Article 820-40 Guidelines for proper grounding and includes a diagram like the one I've attached, which clearly shows that the antenna needs to be grounded as well as the coaxial cable(s) from the antenna at the point where they enter the premises.

Of course, there may be local, state, or federal requirements that supercede the NEC, but your installer should be well aware of those.

OK -- I went to www.dbsforums.com/reviews/tech1_5.html which says:

1. In the case of DBS systems, this issue of bonding the satellite downlead’s ground to the household ground is an area of great discussion. Some people feel that any ground on the coax is better than none (for the shielding and static prevention reasons discussed above). However, using an independent ground for the satellite coaxial cable is, in fact, very dangerous.

2. Grounding your dish structure alone (without a properly designed and installed lightning rod system) is worse than not grounding it at all. It will result in the ENTIRE lightning strike being dissipated through the dish, which is guaranteed to fry your LNB. Ideally, you should have a lightning rod mounted every 20 feet along the highest edge of your roof.

3. Whenever installing a new ground rod, it must be connected to all other ground rods connected to the residence or other building in question. Failure to do this can enable your lamp, air conditioner, satellite receiver and bathtub to all be at various potentials when referenced to each other. In other words, keeping everything at one potential prevents you from being able to touch two devices at the same time and getting shocked.

So please help me out here. I see very contradictory advice given here and at dbsforums. What do most people do? I live in FL, the lightning capital, and want to make this as safe as possible for my family, house and, secondarily, for the equipment.

As for bonding. My electical service meter and ground are on the opposite of the house from my dish installation. To bond a separate ground from the dish area to the service meter area would take a couple hundred feet of copper. What is the proper way to do this?

Thanks.
 
SimpleSimon

SimpleSimon

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Sigh. In practice, he is right and wrong at the same time.

Regarding item #1, the only reason for that statement falls to item #3.

Regarding item #2, if you take a direct hit, the LNBF is the least of your worries. $50 to replace it is nothing compared to the thousands you'll spend on everything else.

Regarding item #3, it's the most contentuous debate across the board. In practice, it's very rare for ground loops to be an issue, and it's usually due to some other fault in the electrical system.

I live in the #2 lightning county in the country, and am a former district fire chief here.
I've seen what ACTUALLY happens. A grounded dish - ANY ground - helps the lightning situation (besides static protection for the LNBF). Static drain is GOOD. Period.

If you take a direct strike, the best you can hope for is that it will follow the coax and stay outside the house. If the coax is grounded, this is a bit more likely than if it is not.

Note that the current will NOT be passing through the coax - not by a long shot. But "encouraging" the strike to stay outside is a good thing. And even at that, you're still likely to take interior damage to the house.

I've seen lots of installs where coax is run through a roof vent into the attic. BAD! :mad: It's a DUH - provide a direct conductive path from the outside of the house to the inside. Get a clue. I also dislike "high" roof mounts for similar reasons.

A million volts at a million amps is the same thing as trying to tell the 600 pound gorilla where to sit. If you stack bananas where you want him to go, he just might do it - but if he doesn't, there's not a dang thing you can do about it.
 
R

R-U-Q-R-U

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SimpleSimon said:
Sigh. In practice, he is right and wrong at the same time.
------
Regarding item #3, it's the most contentuous debate across the board. In practice, it's very rare for ground loops to be an issue, and it's usually due to some other fault in the electrical system.

Thanks for the update. So you are saying that if I cannot bind the dish/coax grounding rod to the meter ground the chance of a a ground loop is rare and should not be a concern?
 
T

Tony S

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I had a feeling that the issue of grounding the dish would generate controversy, however, I feel that in this case the dish itself should NOT be grounded. The original poster said that he was mounting the dish on the roof. If he grounds the dish, he is essentially making the dish into a lightning rod. Since the dish is grounded, and is also high up on the roof, it will give lightning an easy path to ground.

If the dish is grounded and lightning hits it, whether the dish is grounded or not will not matter much, everything connected to it will be fried either way. On the other hand, grounding the coax by using a ground block placed at the point where the cable enters the home makes sense. It dissipates the any static build up in the LNB. Grounding the coax has nothing to do with lightning protection.

If the dish is on the roof and you really want to ground it, you should get a whole house lightning protection system and bind the dish to all of the other lightning rods that are attached to the peaks on the roof. Otherwise, why make the dish into a lightning rod?
 
SimpleSimon

SimpleSimon

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Well, I've never had a problem with it (BTW, I'm an installer, so we're talking about lots of setups, not just my own). I only mention it because a few others have reported problems.

Maybe we're just lucky here - 99% of the installs are in houses less than 10 years old - good electrical systems. Also, we are only a couple of feet above bedrock (Pikes Peak Granite). You can NOT use an 8' ground rod here. 4'ers often "bottom out".

EDIT: Tony S, I think it's already been stated: Ground the dsh to protect the LNBF AND the house. ANY static drain is better than none, and will "discourage" lightning from going that way.

Maybe you're under the impression that putting a 'ground' in the air draws lightning? That's not true.
 
ScottChez

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All done, had the installer out and two electricians out.

Recap: the dish is on the comlete other side of the house, the oposite side of the main house ground. The dish is under an eve on a lower roof, not the top roof.

They put an 8' ground rod in where the Coax enters the house (all coax is on the on the same side of the house as the dish. The Dish is also grounded using that ground wire attached to the Twin coax line.

We did not bound it to the main ground. I do not see any interferance on any tvs or hear any hums on speakers.

Am I safe to say it does not need to be bounded to the main as its so far away and the coax and tvs are also on the other oposite side of the house as the main?
 
R

R-U-Q-R-U

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ScottChez said:
All done, had the installer out and two electricians out.

Recap: the dish is on the comlete other side of the house, the oposite side of the main house ground. The dish is under an eve on a lower roof, not the top roof.

They put an 8' ground rod in where the Coax enters the house (all coax is on the on the same side of the house as the dish. The Dish is also grounded using that ground wire attached to the Twin coax line.

We did not bound it to the main ground. I do not see any interferance on any tvs or hear any hums on speakers.

Am I safe to say it does not need to be bounded to the main as its so far away and the coax and tvs are also on the other oposite side of the house as the main?

I had Dish come and complete the grounding of my system. They installed a 4 foot copper grounding rod and grounding blocks for the coax. He grounded the Dish and the Coax to the rod. The rod was NOT bound to the main service on the other side of the house.

This installer said this is pretty standard and has seen no problems.

Result: No hum or interference. Thanks Simple Simon!
 
ZandarKoad

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Total Frustration

I'm a disnetwork subcontractor, and from my point of view, grounding is all a big crapshoot. I've had two jobs that were perfectly grounded fail a QC check simply because the Quality control guy was too lazy to lift up drop ceiling tiles to LOOK for my ground. :mad: For me, the only reason I ground systems is:

#1 So the system works for the duration I am responsible for it
#2 So it passes Quality Control

I don't CARE about some uniform code in some book somewhere, because the QC guys don't even know about that same code. There have been times when I have been forced to UNGROUND a system to get it to work. I've been told soo many conflicting things concerning grounding I would be forced to quit if I were a perfectionist. There IS no universally right way.

To customers, I say: If the system works, it works. Be happy. To heck with the ground.

To installers, I say: Get grounding standards in writing from your supervisors. Then shove it in their face when your grounds fail QC.

To Quality Control I say: F$#& YOU!!!

:D
 
ScottChez

ScottChez

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Quality Control Guys?

Who are they? If they come to my house do they have to ask before they check anything in the back yard. I dont want a QC check.

Do they call ahead?
 
ZandarKoad

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Don't know for sure. We have a QC guy working for our retailing shop (not actually for Dishnet) and he sometimes calls ahead. If your back yard is gated, he probably won't go back there. But he always knocks first. His name is Pete. Say hello to him for me. :p
 
J

jtravel

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I called Dish Tech support and told them My Dish and Coax had no ground installed by the Installer they sent in Jan.
The Tech told me that in general they should be grounded but its really only needed in some specific areas of the Country and left up to the installers discreation.
I told him the Manual says NEC code requires grounding and to please check with a supervisor if my Dish and coax need to be grounded.
He put me on Hold and came back and repeated the samething he said befor.
I asked about possible damage to the LNBF due to static and he said this is not a issue because the coax sheild is grounded thru the receiver when connected and would drain away any static.
he said he would put a note on my account that shows he and his supervisor told me I didn't need a ground.

Should I keep calling and pressing the issue or just let it go?
 
R

R-U-Q-R-U

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jtravel said:
I called Dish Tech support and told them My Dish and Coax had no ground installed by the Installer they sent in Jan.
The Tech told me that in general they should be grounded but its really only needed in some specific areas of the Country and left up to the installers discreation.
I told him the Manual says NEC code requires grounding and to please check with a supervisor if my Dish and coax need to be grounded.
He put me on Hold and came back and repeated the samething he said befor.
I asked about possible damage to the LNBF due to static and he said this is not a issue because the coax sheild is grounded thru the receiver when connected and would drain away any static.
he said he would put a note on my account that shows he and his supervisor told me I didn't need a ground.

Should I keep calling and pressing the issue or just let it go?

Same thing at my install. But when I called they just scheduled another installer to come out and do the grounding. He did.
 
SimpleSimon

SimpleSimon

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ZandarKoad said:
For me, the only reason I ground systems is:

#1 So the system works for the duration I am responsible for it
#2 So it passes Quality Control
Funny, I do the job right because I want the customer to have a good experience. You should go find another line of work. :mad:

Glad the rest of you guys are now running safe with clean signal. :)
 
R

redhawk

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ZandarKoad said:
For me, the only reason I ground systems is:

#1 So the system works for the duration I am responsible for it
#2 So it passes Quality Control

I don't CARE about some uniform code in some book somewhere, because the QC guys don't even know about that same code. There have been times when I have been forced to UNGROUND a system to get it to work.

:D

And Dish network wanted to know why I didn't want to have an installer come put my system up! (Actually, one of my neighbors does directv installs, and I did get some advice from him.) Too many of these local guys are just average Joe's with little or no understanding of what they are doing.

Disconnecting the ground to get a system to work sound more than a little suspect to me. Sounds like a poor ground system with ground loop problems.
 
K

kirkdj

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Mar 15, 2004
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Same Thing

jtravel said:
I called Dish Tech support and told them My Dish and Coax had no ground installed by the Installer they sent in Jan.
The Tech told me that in general they should be grounded but its really only needed in some specific areas of the Country and left up to the installers discreation.
I told him the Manual says NEC code requires grounding and to please check with a supervisor if my Dish and coax need to be grounded.
He put me on Hold and came back and repeated the samething he said befor.
I asked about possible damage to the LNBF due to static and he said this is not a issue because the coax sheild is grounded thru the receiver when connected and would drain away any static.
he said he would put a note on my account that shows he and his supervisor told me I didn't need a ground.

Should I keep calling and pressing the issue or just let it go?

My installer told me the same thing on April 15th. So what is Dishes offical policy on grounding by the installer....I've heard the NEC codes etc. I would like to know before I call them, because I'd hate to be told some bull told to me, and not know where I stand. The thing is this same coax, that they say is grounded by the 110v plug ground, is hooked up to my $2500 tv/surround sound system....they'yy replace their boxes, what about my tv etc.?
 
SimpleSimon

SimpleSimon

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Well, one thing for sure - grounding is NOT the same thing as surge suppression - not by a long shot.

And in any event, E* (or D*) is NOT going to take responibility for your other boxes.

Install surge suppressors - NOW. Belive it or not, I use the CyberPower ones from Wal-Mart. Half the price of any others, great specs, and have always worked flawlessly - even here where the power blinks OFTEN because we're the #2 lightning county in the USA.
 

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