phone line lightning protection

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Red Squirrel

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It just occurred to me, I have no lightning protection for my phone line which leaves me open to equipment damage should lightning hit, as it would hit the modem then possibly the whole ethernet network. It does not pass anywhere near a UPS or power bar that has phone line protection capability. Can I just get a surge bar near the demark and pass it through there? Does the surge bar have to be plugged in even if I don't need it for power? (I'm guessing yes, because of the ground) Or is there a better solution, given I'm only looking to protect the line?
 
You absolutely need a ground connection (otherwise you won't have any potential difference across the metal oxide varistors which actually conduct the surge current).

Keep in mind taht there are products designed just for phones, which would be smaller, maybe easier to locate.
 
There is protection at the network interface (NID) that the phone company installs. These are gas tube or carbon protectors.
 
Hmm was thinking that too. I do have a NID. And working for the phone company (but not the actual phone department) I have heard references to carbon protectors on various occasions. So are these good enough or should I still install my own means of protection?
 
A surge protector and something that can stop a lightning strike are very different.

If lightning directly strikes your phone or power line it will easily jump through a surge protector and fry it and everything else it its path.

I believe you need some pretty industrial equipment to stop a lightning strike.

Consumer surge protectors are just made to stop smaller surges in power.

I'm sure if you look in the right place you can find something to shield yourself from lightning.
 
Every phone line has a protector...if you don't have a NID, there is still a protector...
 
Also, keep in mind, the quality of the ground connection is very important. I don't think you want to go full monty on this, but SOP in the broadcast industry is to use very wide copper straps (you need to minimize inductance, the actual lightning strike is a ~10uS pulse, which is effectively RF). I mean, chances are the only thing coming off that POTS line is just a regular desk phone.

The major issue you are going to have with lightning is finding a device that can operate fast enough, and can dump that amount of current to ground. The ideal setup would be to put an enclosure outside, and have a copper strap going straight into a grounding rod.
 
Hmm did not figure it was this involved. How do people in Florida do it? Don't they get tons of lightning storms there? We don't get much lightning here, but I just want to be prepared if ever one does hit a line as I can't afford to replace every single device on my network not to mention deal with the data loss, having to restore offsite backups and so on.

Will the carbon protector do the job or does that not cut it?
 
lol don't know why when I read that post I thought it was directed at me even though it had your name in it. Ignore my response. Not sure what I was on that day.
 
Maybe these guys have something for a telephone line:

http://www.deltala.com/products.htm

I have one of their units installed in my circuit breaker box at home. Last summer lightning struck a pole near my house and it burned out almost every surge protector power strip in my house and damaged some of my electronics and even my microwave. A neighbor across the street had a fire start in his basement from the event. I ended up replacing all of the 55-year old wiring in my house and some of it had burned cloth insulation.

I decided to install the lightning arrestor but it's difficult to say if it works, hopefully it does.
 
Red Squirrel said:
Hmm did not figure it was this involved. How do people in Florida do it? Don't they get tons of lightning storms there?
Click to expand...

Since I live in Florida and we do get tons of lightning storms and I run everything at home through the beefiest surge protectors I can afford. I've had lightning blow out a few APC units but the equipment attached was spared. I've got a buddy who lives in close proximity to me and he says surge protectors are a waste of money and it seems like he's always replacing something that's been fried from the lightning.

At work I just realized we only have whatever the phone company installed, which I don't think is a whole lot. The problem with the company I work for is they're more reactive than proactive, so I doubt we'll be able to get management to sign off on any kind of upgraded solution until we lose some equipment due to poor planning.
 
Red Squirrel said:
Hmm did not figure it was this involved. How do people in Florida do it? Don't they get tons of lightning storms there? We don't get much lightning here, but I just want to be prepared if ever one does hit a line as I can't afford to replace every single device on my network not to mention deal with the data loss, having to restore offsite backups and so on.

Will the carbon protector do the job or does that not cut it?
Click to expand...

I lived in florida. We had a NID. The lightening just burned the circuit protector, they just came and replaced it. Nothing after the NID was damaged.
 
Cheetoz said:
I lived in florida. We had a NID. The lightening just burned the circuit protector, they just came and replaced it. Nothing after the NID was damaged.
Click to expand...

That's good to know, so guess I'm fairly safe then. I'll have to open up the nid to confirm but I'm guessing there is a protector in there.
 
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