Dish and wiring issues

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Old 07-25-15, 10:47 AM
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Dish and wiring issues

We called for a new installation (a third receiver for a third, new, TV) and the installer said we have voltage from the splitter on the outside wall to the ground wire. It varies, but is currently around 15 volts. We are using a multimeter tester to check. The installer said often old tube TVs or old surge protectors are the issue, causing voltage backfeed in the ground.

True, the tester used from the splitter to the ground wire shows voltage now. But from the splitter to a lag bolt on the adjacent deck ALSO shows voltage, about 10 volts. We would think that the bolt is insulated via the wood of the deck framing. Testing from the bolt to the ground wire shows no voltage. Wouldn't this mean that the voltage is coming from the splitter, not the ground wire?

Also, there are two different ground wires attached to a metal pipe which holds the electrical meter. (The old cable system was and now the satellite splitter is grounded to that pipe; one wire is now connected to a grounding rod, the other is loose in the vicinity of the splitter.) Testing from one ground on the pipe to the other, a distance of maybe 20 inches, shows no voltage. It looks like there is no voltage in the actual ground.

The dish company will not touch anything -- even if it's their equipment that is defective -- so long as they get voltage at the splitter. They're calling it ground voltage, but we're seeing splitter voltage. We really don't want anyone hurt.

But we had wanted a third TV connected to the dish system. We have new surge protectors, and have disconnected the oldest TV (deep, not a flat screen, which ironically seemed to be pulling about 4 volts out of the 'backfeed' when we pulled its plug while the installer was here before). We found an outlet with a hot/ neutral reverse and corrected that. But today the installer is coming back and we still have 15 volts showing between splitter and ground wire.

Are we understanding this wrong? We have pored over the Forum, but aren't finding answers specific to this situation.
 
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Old 07-25-15, 12:32 PM
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Exactly how is the ground voltage being determined? LNB's produce voltage to operate. Maybe the installers aren't qualified. They must add an additional LNB splitter to distribute to the third set. I may be off base, but the others will certainly chime in and offer better solutions.
 
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Old 07-25-15, 02:35 PM
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The Dish splitter should have been grounded on installation. There should not be any voltage between the splitter and ground.

At this point we can assume the splitter was not grounded properly on the first installation. That doesn't surprise me in the least based on some of the work I've seen from their installers.

At the splitter.... disconnect all the coax connections going to TV's. Find which ones is supplying the unwanted voltage and then go from there. You'll need to test the shield from each coax to ground with a meter.
 
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Old 07-25-15, 02:38 PM
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What kind of meter are you using. Make, Model, type. (Digital or analog) This could be just phantom voltage. Can you see it/feel it? 15 volts is so low you may not be able to feel it.

I would start turning things off to determine where the voltage is coming from. I suggest starting at your electrical panel, and while watching your meter, have a helper turn off breakers one by one until the voltage disappears. If you find it, turn the circuit back on and find what is on that circuit and unplug each item until the voltage disappears again. This will narrow down where it is coming from.
 
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Old 07-25-15, 05:08 PM
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In reverse order (to Tolyn), we bought a Southwire Multimeter, 10030S, digital. The installers were finding the same voltage. See? Feel? No to both. In the near future we now know to do what you said, because this is an old house with old wiring, and there is a lot to check. Thank you. We finally got an installer/technician who was capable of fixing the issue; we had not expected that!

As you said, PJMax, the satellite company doesn't have good installers. In fact it has none. It contracts out all its work, and some techs are not trained well (or forget the numbers for the voltage non-issues and just refuse to work on systems if there is ANY -- apparently there are valid thresholds, just not zero, only).

The man who installed today had to redo the initial install from four years ago because much was wrong. There were two sets of splitters, and parts that were incorrect; I don't remember all that was wrong. But we now have TV, in fact three, and three receivers and one dish that also work. Since this has been ongoing for a year, we're still holding breath, but breathing a bit easier. The coax connections were replaced because the splitter was replaced; even the electrical in (not right) was replaced. The two existing receivers were failing, and they also were replaced.

Chandler, the ground voltage was determined via a meter like ours (longer contact points/ metal ends, so easier to use but otherwise basically the same, if pricier). One prong/ contact was placed at the splitter under the screw head for the ground wire (wire disconnected), and the other was touching the exposed metal of the ground wire.

Apparently (we knew this from reading the Forums) there is customary backfeed from new/er TVs, so the demand for zero voltage was probably quite unrealistic. Anyway it's fixed, fingers crossed. We've found this awesome Forum, and look forward to learning more. One of us used to install HVAC systems and has electrical stories, and the other (me) is a total beginner in wiring, but not in carpentry and tear out. Thank you all for the quick response, and detailed questions along with answers.
 
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Old 07-25-15, 05:19 PM
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we bought a Southwire Multimeter, 10030S, digital.
Only a few very expensive digital meters have the circuits to distinguish between real voltage and induced and capacitive voltages. On the other hand even a cheap analog multimeter will usually clear ghost voltages because of their much lower impedance. http://support.fluke.com/find-sales/...105317_A_w.pdf
 
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