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Proper grounding of phones for a remote house 17,000 feet from main line.

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SsgKen

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This discussion was started in Alt energy here https://www.electro-tech-online.com...y-to-charge-a-24vdc-battery.92560/#post734482


I am on my second 12 phone main entrance box in my remote cabin. I was wired for 12 lines in case I wanted to put in a bed and breakfast or so they told me. I now wonder if they knew they would be out once or twice a year. Phone was installed in 1992 and by 1999 I was down to my last good input. 11 were nuked by lighting along with two computer modems, one laptop, and a dozen ten dollar phones. The ground was checked every time by Ma Bell but with 17,000 feet of buried line it must pick up enough lighting to defeat the grounding system. Three more phones were put in by neighbors but the closest one is still 3000 feet away. Its more now because the closest neighbor dropped his land line because they could not remember to unplug the phone.

QUESTION: Do the phone companies count on having a grounded phone every few hundred feet for a combination ground of sorts? Is there a realistic ground for this situation? By realistic I do not want to dig a trench around my house and bury 4/0 buss bar. Nor even at the old 80 cents a pound.
 
17,000 feet on poles or underground?
 
buried

It is underground. It goes through some swampy areas too. The wet areas could be several hundred acres.
 
thank you one and all

The Ufer ground may do it. I just have to dig down a little to expose the concrete slab and find a re bar rod somewhere. I hope he used them.


To appreciate the limitations of lightning protection systems, it is important to understand the magnitude of lightning's energy. Because of the high electrical potential of lightning (often exceeding 100 million volts and 40,000 amperes),

There is not a lot of amps coming up the phone line but enough to fry modems, and telephones. No damage to devices not in a phone line.
 
After the first strike why didn't you buy a surge protector? They don't cost a lot and they often come with insurance policies that will fully cover any connected equipment.
 
After the first strike why didn't you buy a surge protector? They don't cost a lot and they often come with insurance policies that will fully cover any connected equipment.
I always wondered what percent of the cost of a protector is the premium on the insurance policy; perhaps more than half.

If there is a 10% chance that a $2k appliance will be ruined over the life of the protector or appliance the premium should be ~1.1 x $200.
Therefore, the chance is probably much lower than 10% or the cost of the average appliance that is vulnerable is much lower than two kilobucks.
It's a numbers game.

Mr. Ken, how many strikes did you have in those 7 years?
 
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I was aware of power line protectors and I had several. I never lost a device from a 115 volt line. It was too hard to unplug every phone when we both left. All we lost were those ten dollar phones. It would have been hard to put a protector on the kitchen wall outlet so it just stayed in until it got fried.

Twenty strikes for sure. I had to abort computer operations many times by just unplugging it.

Storm here...more later.
 
Twenty strikes for sure.
84 months/20 = one/week, so your likelihood is ~100%. This means you should spend as much on protection as your equipment is worth. Phone line protection should be cheaper because the normal current is small.
**broken link removed**

I have been unable to find data on lightning strike likelihood, given a ZIP code. It's gotta' be somewhere!
 
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SSgKen... They make them for phones too, and cable..
 
An animal was digging a hole under the foundation slab. I am going to dig it deeper and try grounding to the foundation.

Thanks everyone
 
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