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Discussion Starter · #1 ·
Earlier this week my cable went out. Technician that was fetched found the main cable line coming into the house burnt (see below). The burnt end was on the cable coming from the pole to the house right before a 3-way splitter (grounded) that then sends the signal into the house.

The technician said that according to his knowledge it is called "back feed" and it usually happens when ground is swapped with one of the cables in an outlet or if there is a general fault somewhere in the house. He added that this is the theory that he was taught and does not for sure.

I should add that I recently changed multiple outlets and light switches in the house (approx 3 weeks ago). Today I checked all changed outlets with a multi-meter (between the hot-cold) and they all show 115-125.

My question is:
1. Is the tech correct with his analysis or could it be a cable company issue?
2. Assuming fault is in the house, did I test it correctly and if not how do you test if cables are swapped in an outlet?
3. Could this be cause due to swapped wires in a light switch and if so, will light still work?
 

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I'm pretty sure what that tech told you is total BS. The incoming cable should be separately grounded and would not be affected by electrical issues in the house.

If you don't have an outlet tester, a quick way to check them is to see where the black and white wires are connected. Assuming we're talking about three-prong outlets, the white wire should be connected to the larger slot and the black to the smaller.
 

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Confirm....it was burnt at the 'grounded' 3 way splitter on the pole side?

If so....lightning strike.....

Or....someone energized the shield side of the coax....maybe one of your neighbors? Because the burn was on the outside....your grounded splitter did it's job. It grounded the signal like it was supposed to. If the issue was on your side, then I would expect that the burn would have been on your side.
 

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Discussion Starter · #6 ·
Thanks guys for all the help.

Wanted to confirm, burn was in the cable coming from the pole to the house at the point where it enters the splitter. Nothing past the splitter got damaged so it would make sense that isn't related to the connection within the house.

I live in Las Vegas, NV where lightning are quite rare though I my new neighbor is sketchy...
 

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The technician is an idiot, and should be reported to their company. I have found that the majority of catv techs, just like Satellite installers, usually were flipping burgers or pushing a broom a month before they got let loose in the wild.

If it was me, I would be calling in a licensed electrician and the power company, to look things over, if there was signs of possible voltage on the line. If no voltage is showing on the coax between shield & stinger, or stinger & ground, or inside of splitter and to casing or ground, then most likely a lightning strike, or had a line issue that was caused by something dropping across the phases and Neutral.
 

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Thanks guys for all the help.

Wanted to confirm, burn was in the cable coming from the pole to the house at the point where it enters the splitter. Nothing past the splitter got damaged so it would make sense that isn't related to the connection within the house.

I live in Las Vegas, NV where lightning are quite rare though I my new neighbor is sketchy...
The soil in Vegas is not the best for grounding, so it is possible that you just had a poor grounding issue, because of your soil type. BTW, what do you mean that your neighbor is sketchy? If the neighbor is doing something illegal, report them.
 

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I would be very easy to determine if the thermal damage was related to ground current. With the cable repaired utilizing an amp clamp measure for current.

Depending on how you systems are grounded, shared utility power transformers, grounded services, grounded coax at two or more houses, it is quite possible for there to be ground current on any metallic components that are common house to house, gas pipe, water pipe, coax cables
 

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Soil type has a lot to do with grounding systems. Suggest you read up on it.
Soil type has NOTHING TO do with ground current. Except as noted below

Soil type and grounding electrodes have to do with lightning strikes and accidental connections of utility to primary to the secondary.

If you are saying this was a lightning strike issue you might have a point but a number 4 or 6 awg. to a one or two electrodes in good soil with the typical installations of tight bends in the conductors an acorn nut connection. LITTLE OR NO HLEP.

Lightning will take all available paths including across insulator/
 

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Soil type has NOTHING TO do with ground current. Except as noted below

Soil type and grounding electrodes have to do with lightning strikes and accidental connections of utility to primary to the secondary.

If you are saying this was a lightning strike issue you might have a point but a number 4 or 6 awg. to a one or two electrodes in good soil with the typical installations of tight bends in the conductors an acorn nut connection. LITTLE OR NO HLEP.

Lightning will take all available paths including across insulator/
I really do not know where you are getting that I am the one that stated that this was a lightning strike. Suggest you go back and re-read the whole thread.

As for soil conditions, YES it has a lot with how well of a ground you will have for your Earthing Ground. Your name know a little is exactly that. Try stopping and doing research, before going off on some tangent, that you have no clue about what is going on in a thread, such as reading the whole thread, then just picking one post to pick apart.

To make things easy on you, since you seem to have a difficulty in knowing much on this subject, see the following:

http://www.scribd.com/doc/142157082/SOIL-RESISTIVITY-AND-EARTHING-SYSTEM-pdf
http://support.fluke.com/find-sales/Download/Asset/2633834_6115_ENG_A_W.PDF
http://www.cder.dz/download/upec-7.pdf
http://www.lightningman.com.au/Earthing.pdf
http://en.wikipedia.org/wiki/Soil_resistivity

BTW, I can keep pulling this info all day long, and have the knowledge also to back up what I am stating. So, before you start tearing into people, thinking that they do not know what they are talking about Know a Little, suggest you step back and do your own research on the subject matter first, along with keeping it on topic, vs. tearing apart what others are posting.
 

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I really do not know where you are getting that I am the one that stated that this was a lightning strike. Suggest you go back and re-read the whole thread.

As for soil conditions, YES it has a lot with how well of a ground you will have for your Earthing Ground. Your name know a little is exactly that. Try stopping and doing research, before going off on some tangent, that you have no clue about what is going on in a thread, such as reading the whole thread, then just picking one post to pick apart.

To make things easy on you, since you seem to have a difficulty in knowing much on this subject, see the following:

http://www.scribd.com/doc/142157082/SOIL-RESISTIVITY-AND-EARTHING-SYSTEM-pdf
http://support.fluke.com/find-sales/Download/Asset/2633834_6115_ENG_A_W.PDF
http://www.cder.dz/download/upec-7.pdf
http://www.lightningman.com.au/Earthing.pdf
http://en.wikipedia.org/wiki/Soil_resistivity

BTW, I can keep pulling this info all day long, and have the knowledge also to back up what I am stating. So, before you start tearing into people, thinking that they do not know what they are talking about Know a Little, suggest you step back and do your own research on the subject matter first, along with keeping it on topic, vs. tearing apart what others are posting.
Missed that:thumbsup: Sorry for the confusion

But I do not need your links (though I will read them) I do grounding investigations, lighting investigations, ground testing and investigate grounding issues.
 

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Earlier this week my cable went out. Technician that was fetched found the main cable line coming into the house burnt (see below). The burnt end was on the cable coming from the pole to the house right before a 3-way splitter (grounded) that then sends the signal into the house.
I would bet money this is the result of a loose or open neutral on your service. The technician's explanation is total BS, and lightning is highly improbable. This is EXACTLY what happens when your service neutral is interrupted and there are no other paths for that current to return other than on the shield of your cable coax. This is a dangerous condition that can cause fire ans shock hazards. You should probably have an electrician check it out. With a clamp-on ammeter, it's easy to see if there is objectionable current on the coax.
 
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Missed that:thumbsup: Sorry for the confusion

But I do not need your links (though I will read them) I do grounding investigations, lighting investigations, ground testing and investigate grounding issues.
I will excuse you then. Sorry for being hard on it. I am finding that there are just a lot out there, that do not know how soil conditions can affect the Earthing ground at a structure. I have also found that a lot do not realize that our electrical system has not changed much over the years, from when we were using Single phase systems, which is still active in some areas.

My brother ran into this same exact issue as the OP, due to he has a Single Phase Electrical distribution system to his home. His soil is thin, due to about a foot or so under is just Limestone. He ended up having an electrical fire, due to lost return path for the electrical system. If he did not have his TWC coax hooked up, it would have been worse, since it acted as a return path. My brother just lost a few inches of wire down in his fuse panel, because of it, no other equipment.

But for the OP, they really need to report that tech to the company, that they are misinformed how this all works.
 

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I will excuse you then. Sorry for being hard on it. I am finding that there are just a lot out there, that do not know how soil conditions can affect the Earthing ground at a structure. I have also found that a lot do not realize that our electrical system has not changed much over the years, from when we were using Single phase systems, which is still active in some areas.



But for the OP, they really need to report that tech to the company, that they are misinformed how this all works.
I would think when it comes to issues outside a bad picture they are clueless.
 

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My brother ran into this same exact issue as the OP, due to he has a Single Phase Electrical distribution system to his home. His soil is thin, due to about a foot or so under is just Limestone. He ended up having an electrical fire, due to lost return path for the electrical system. If he did not have his TWC coax hooked up, it would have been worse, since it acted as a return path. My brother just lost a few inches of wire down in his fuse panel, because of it, no other equipment.
They wouldn't do that on the secondary side of the transformer, only the primary… It's a code violation not to run a grounded conductor.
 
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