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Be kind - this is post #1.

I've read many of the grounding threads and still have a question. I have an install coming this week and I'm a little concerned about the grounding of the dish.

My house is a 2 story colonial (salt box) with an attached 3 car garage (no living space above the garage).

The dish will need to go on the 2nd story roof for LOS. My utility service enters through the the far wall of the garage so that's probably around 30 feet from the house itself.

Here's where I get confused. If the dish is mounted on the roof, it's my understanding that it and the coaxial needs to be connected to a grounding block where the cabling enters the house. Also, the grounding block needs to be connected to the grounding rod used for the electrical utility and this should be no more than 20 feet to meet NEC code.

So, the dish is probably 30' away and about 10' higher than where the grounding block would be. Is this a problem?

I'm also a little concerned about losing about 60' of RG-6 run to go from the house to the outer wall of the garage and back again, but that's what it is.

Just wondering if I'm understanding this right. Any thoughts? The install is being done by Dish but the grounding seems a generic question so I may post this on the Directv forum also.

Thanks and yes, I'm a noob.
 

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Godfather
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The ground location will not be an issue. You can place the grounding block anywhere along the (max 200' for DP or DDP. max 100' Legacy) run. If you have copper water piping the tech would be able to ground to that as well. We are also allowed to ground to the AC compressor service disconnect (at least my company tells us we can). The 20' rule applies to the distance from the ground block to the ground source itself.
 

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I cannot stand grounding to the water pipes!

I've known personally (not urban legend) several people (including my father-in-law) who have been "bitten" by AC when removing water heaters. Their body becomes the ground plane when they removed the hot water tank and accidentally grabbed both pipes. Fortunately in my father-in-laws case, the home owner was right there to turn off the breakers when this occured, until then the current locked his hands to the pipes and he couldn't let go.

Very, very, very lucky........

Granted, if it's just the dish, you should only have that happen if you are replacing the tank at the same time of an electrical strike on the dish, but still..

Our home, which is exactly as you describe (multi-story) has a second grounding rod for the dishes. This grounding rod is then also bonded to the original grounding rod with a burried super heavy guage copper wire.

Guess your install experiences will vary.
 

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In addition to getting shocked, grounding on the water pipes is simply not a good idea, period. Some homeowner will put a in piece of plastic pipe between the house and the supply valve and leave the system essentially ungrounded. Water pipes are for water.
 

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Legend
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phrelin said:
In addition to getting shocked, grounding on the water pipes is simply not a good idea, period. Some homeowner will put a in piece of plastic pipe between the house and the supply valve and leave the system essentially ungrounded. Water pipes are for water.
I agree,but what if that is the only option?Dish say's it must be grounded.I have installed in some houses that only have a ground on the service pole or in some cases vinyl siding was installed over the original ground.

I am not dissagreeing, just asking your opinion.In rural America,everything is not up to code.
 

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I would use a ground rod for the dish and/or an antenna. Click on the picture below to go to the page at Cables To Go:



Of course, this is not a suitable substitute for an ungrounded outlet for the receiver/DVR/TV.
 

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IIP said:
4' grounding rods don't meet NEC, which requires at least 8'.
Correct. This is not intended to ground the 120v electrical circuit. The assumption is that the household power is grounded. It only provides supplemental grounding for the dish or antenna.
 

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phrelin said:
Correct. This is not intended to ground the 120v electrical circuit. The assumption is that the household power is grounded. It only provides supplemental grounding for the dish or antenna.
Ok. Can you cite the code that says this 4' supplemental electrode is allowed? Does it have a UL listing? The fact that the dish doesn't normally carry line voltages has nothing to do with how it is grounded. The dish must be bonded to the grounding electrode of the structure it serves; period.
 

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Sounds to me like the OP has a good grasp.

With that said....
brant said:
Ok. Can you cite the code that says this 4' supplemental electrode is allowed? Does it have a UL listing? The fact that the dish doesn't normally carry line voltages has nothing to do with how it is grounded. The dish must be bonded to the grounding electrode of the structure it serves; period.
I'm not arguing with you. I was responding to the idea of grounding a dish or antenna to the water system as in this case:
Satpro92 said:
I agree,but what if that is the only option? Dish say's it must be grounded. I have installed in some houses that only have a ground on the service pole or in some cases vinyl siding was installed over the original ground.

I am not dissagreeing, just asking your opinion. In rural America,everything is not up to code.
Now, about antenna grounds. Grounding anything to water pipes is a big fat "No way!" as far as I'm concerned, code provisions or not. The nice folks at Channel Master published an antenna installation manual a while back, a long while back. Here's a link to its grounding instructions. It was a satisfactory solution to my problem. You see, Dish Network's contractors, those professional installers who installed my dishes, simply didn't ground them! The cables ran out of the dishes, through a hole in the wall, across the ceiling, and down to the boxes.

I thought that any rod in the ground would be better than that. Yep, it should be bonded to the house grounding system. And I'll get around to that.
 

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phrelin said:
I thought that any rod in the ground would be better than that. Yep, it should be bonded to the house grounding system. And I'll get around to that.
That's a common misconception for some reason.

You now have two grounding electrodes for your service that are bonded by the coax; that's not a good thing.

What you have done is set the dish at a different grounding potential than the service grounding electrode.

Current looks for the path of least resistance back to its source; ground rods are set at the service and the transformer serving your house and the earth is used as a path between the two.

What is now possible is the ground rod on your dish could become this path of least resistance (although the chances are slim), and any leakage current could travel through the coax, dish, and that 4' ground rod. This could cause serious damage to the equipment connected to the coax or short the coax.

I'm not an absolute expert on the total damage that could be incurred, but I have seen firsthand equipment that has been destroyed because of this very scenario.

I'm not saying your house is going to burn down tomorrow or all of your equipment will get fried in the next lighting storm, but it is a dangerous situation that should be corrected soon.
 

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brant said:
...it is a dangerous situation that should be corrected soon.
Agree, but after waiting a year with crappy 129 reception which I only got by having the two original installers and then a trouble shooting tech come out, I had a third trouble shooting tech come out, move the wing dish around and put it back where it was saying it was the best he could do. So I moved the wing dish myself improving the signal by 20% and that's when I noticed there was no ground block anywhere in the system. It's not a simple run to the house ground, so this was temporary.

Leakage current. For some dumb reason I thought the DVR's were grounded. Now I can't remember, so I'll have to check tomorrow.:confused:
 
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