Satillite Dish not grounded properly

[millie66]

On June 17, 2006 we had a pretty nasty storm. I believe my house was either hit by lighting or my house took a powerful surge.

My ac unit that goes upstairs was knocked out, my alarm system had to be unplugged to get it to stop, my projector in my media room dead and my sprinkler system was also out.

When I had the ac folks out they said that my satellite dish was grounded through my AC disconnect and not a control panel. So everything that was not on a surge protector and not necessarily needing a sure protector was knocked out. So far the AC unit the controller and transformer had to be replaced. I had to replace the entire sprinkler box. I bought a new back up battery for my alarm system and the 2 trouble codes are AC failure. There is power coming from the outlet. The projector that one hurts the worst. It is an older model and most likely will have to be replaced.

Ok so I called SBC and told them I want to file a claim. After 2 weeks I finally was able to get someone out to my house. He took a picture of the dish and how it was hooked up. All he would say to me was that "this is the standard procedure of how we hook them up and that the dish would be burned up if it was hit by lightening." I told him that I agreed that it looked fine and that was why I said that I felt that my house took a surge through this line. So now I'm climbing the ladder and they are not being very helpful. No one calls me back and so on.
Can the dish look fine and all of this still happen? My AC guys think so. The SBC guy said to me that is gets grounded eventually to the electrical panel in my garage. I told him it had to go through my house to get there and that does me no good.
Just need some opinions to help me decide to keep going with this or give it up and do with out a projector for a long long time.

 

[Smart $]

First, this forum is for those in the electrical or directly-related trades. An occupation as "customer service supervisor" will likely be assumed as not meeting that requirement and this topic may be closed at any time by a Moderator.

IMO, your attempt to prove fault will be fruitless. Judging solely from your description, the "dish" is not properly grounded. However, unless you can prove the "dish" took a direct lightning hit (there would be definite visible signs if this did in fact occur) this will not give you a course to pursue. I say this because lightning strikes generate an electromagnetic pulse (EMP) in the nearby area and that will induce an electrical surge on any conductive material within that area. A bolt of lightning could have hit directly or near a power company distribution line a substantial distance away from your residence yet still send a surge on the lines to your property. This is more likely the cause of your headaches.

Suggest you contact your homeowner's insurance agent to see if it is covered...

 

[George Stolz]

Millie, the satellite dish was not connected in an appropriate fashion.

For what it's worth, it is highly unlikely that connecting it in the most code-compliant fashion would have made any significant changes in the outcome of events from the storm, in my opinion.

An accessible bonding point must be provided at service equipment or the disconnecting means of separate buildings or structures for communications systems. The point can be any one of the following:

(1) An exposed, nonflexible metallic raceway.
(2) An exposed grounding electrode conductor.
(3) An external connection approved by the authority having jurisdiction.


FPN No. 2: Communications systems must be bonded together. Figure 250–134

• Antennas/Satellite Dishes, 810.21
• CATV, 820.100
• Telephone Circuits, 800.100

Author’s Comment: The bonding of all external communications systems to a single point minimizes the possibility of damage to the systems from potential (voltage) differences between the systems.

It was connected to the Grounding Electrode System, in a way. It wasn't connected in the right spot, but I don't see how it would have made any difference in this case. Note Mike Holt's comment - the connection is for bonding purposes more than grounding.

Edit x 2: Consider the sprinkler and the burglar alarms. Suppose the dish took a direct hit. That would put the surge in line with the A/C, explaining it's demise. But the sprinkler and burglar alarms took damage as well. All of the equipment was bonded together, so it would rise and fall at the same potential, as it should. Never the less, many components were still damaged.

I guess what I'm saying is, it's an unfortunate incident, but there is no evidence that the equipment in question would be spared if the dish was bonded at the service as it should have been, as opposed to the A/C disconnect where it was physically connected.

 

[petersonra]

The bottom line is that even proper grounding of these items will provide only a minimal level of protection. lightning goes where it pleases and you will not channel it away from where it wants to go with a #10 wire.

the idea is to try and keep all the metal parts at the same potential to reduce the chance of any current flow at all through the metalic parts.

 

[tom baker]

Milli66
This topic has come up before. and we on the forum agree that only a small fraction of the satellite dishes are installed per the NEC. I never seen one in Washington State done correctly.
1. this is the standard procedure of how we hook them up and that the dish would be burned up if it was hit by lightening."
In that case they have installed every one incorrectly.
2. It may not be possible to protect against a direct strike but certainley a nearby strike can be protected against.
3. Ask your satellite installer:
Do they have a copy of the NEC?
Have they read the requirements in Art 810 and 820?
Did they take out a permit/inspection?
3. Ask if they know what a single point ground is.
4. Are they certified/licensed/bonded?

All the low voltage lines into the house must be protected with some type TVSS, along with the power. All need to be bonded together, ideally very close together. In a lighting strike the voltage of the ground is elevated, but since all is bonded and grounded, the voltage difference is minimal, No voltage difference, no current flow, no damage

Keep going. Ask my quesitons above.
We need to educate the installers who are doing incorrect and unsafe installations. I'd be happy to go one on one with your installer.

And for you, invest in some TVSS. In my house the one I has cost $200.
Plus a point of use at the TV that $40. The one for my digital projector I use on the road was $75. Get a plug in TVSS with coax and RJ-45, this will create a single point ground right at the TV.

I'll be waiting to hear from your installer.
Tom
Moderator.
Cell towers can take a direct lighting hit with no damage.

 

[millie66]

Thank you for all of your comments. I don't think my house had a direct hit of lightening I think that it did take a powerful surge. So even if it was from lines a distance away with the way my dish is installed would it not have traveled through this way?

Everything that is connected to this area is what was zapped.

Also would you all recommend that I get an electrician to come out check it over and if he agrees have him write up a report?

Thank you again and I am going to continue this, I'm now climbing the ladder with SBC. It's just getting them to call me back.

 

[George Stolz]

Millie, Tom is much better versed on this subject than I could hope to be. I hope you take him up on his offer.

At some point in the near future, I will need to read up on the details of 810 and 820.