Lightning protection for incomeing phone lines

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SparkyRules

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I am stringing overhead outdoors a 100Pair phone cable between 2 buildings at a plant. I understand I need to put in UL listed lightning protection. Do I need this at each end of the cable or does one unit cover both ends of the cable? Also how far into the building can this protection be placed? I do not find this code anywhere.









I paid for my education, look at the changes orders I don't get paid for! :lol:
 

kwired

Electron manager
Location
NE Nebraska
I don't know that I have an answer, but can't imagine it wouldn't cost a lot less to run fiber between those buildings, and have more ability than 100 pairs of conductors have.
 

GoldDigger

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I am stringing overhead outdoors a 100Pair phone cable between 2 buildings at a plant. I understand I need to put in UL listed lightning protection. Do I need this at each end of the cable or does one unit cover both ends of the cable? Also how far into the building can this protection be placed? I do not find this code anywhere.









I paid for my education, look at there changes orders I don't get paid for! :lol:
You need protection at both ends, since the two ends of the cable could be at different voltages as the result of, for example, lightning induced surges.
And I would make sure that the protection is as close to the entry point as practicable, certainly before the wires run near any other wires.
 
I am stringing overhead outdoors a 100Pair phone cable between 2 buildings at a plant. I understand I need to put in UL listed lightning protection. Do I need this at each end of the cable or does one unit cover both ends of the cable? Also how far into the building can this protection be placed? I do not find this code anywhere.

I doubt that you can find UL listed protection. You need one set on each end. The phone termination boxes are ususally located right inside of the building and distributed as single pair from thereon. All these rules were outside of the NEC when we had one phone Co. (Ma' Bell had her own rules) and was never really established as a National Standard.
 

dereckbc

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YOu will need protectors at each end preferable right at the building entrance. There are many on the market for sale in all price ranges. For 100 pair is getting into some fairly significant dollars. Something along this line is what you are looking for. Note this is only for the termination blocks and does not include the 100 plug-in Gas tube protectors that will be needed. The protector modules are color coded per voltage.
 
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GoldDigger

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YOu will need protectors at each end preferable right at the building entrance. There are many on the market for sale in all price ranges. For 100 pair is getting into some fairly significant dollars. Something along this line is what you are looking for. Note this is only for the termination blocks and does not include the 100 plug-in Gas tube protectors that will be needed. The protector modules are color coded per voltage.
And, for weressl, these are UL listed. The phone company may or may not be required to use UL-listed products only, but the OP certainly is. This is communications wiring, not telco wiring if the telco does not install and maintain it.

There was a thread on exactly that subject (except maybe a 50-pair cable) here about a month ago.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
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EC
... I understand I need to put in UL listed lightning protection. Do I need this at each end of the cable or does one unit cover both ends of the cable? Also how far into the building can this protection be placed? I do not find this code anywhere.

800.90 Protective Devices
(A) Application. A listed primary protector shall be provided
on each circuit run partly or entirely in aerial wire or
aerial cable not confined within a block. Also, a listed primary
protector shall be provided on each circuit, aerial or
underground, located within the block containing the building
served so as to be exposed to accidental contact with
electric light or power conductors operating at over
300 volts to ground. In addition, where there exists a lightning
exposure, each interbuilding circuit on a premises shall
be protected by a listed primary protector at each end of the
interbuilding circuit.
Installation of primary protectors shall
also comply with 110.3(B).

800.90(B)
The primary protector shall be located in,
on, or immediately adjacent to the structure or building
served and as close as practicable to the point of entrance.

Also see 800.48 Unlisted Cables Entering Buildings because I hope you are using an OSP cable, not a PVC jacketed indoor cable ty-rapped to a clothesline.

You are going to need BEPs here (building entrance protectors with the right plug-in protectors) and splice cases. 100pr is a lot to deal with. Might be that you would be better off subbing this out because in my experience something like this can go south pretty quick if you have no telecom OSP experience.

-Hal
 

dereckbc

Moderator
Staff member
Location
Plano, TX
And, for weressl, these are UL listed. The phone company may or may not be required to use UL-listed products only, but the OP certainly is.
I have been in TELCO some 30+ years and have never known any protector or equipment installed in the customer premisses that was not UL.

As for what goes in the actual telephone switch office and cable pedestals are quite robust and heavy duty more so than what you can find in customer premisses equipment. I certainly cannot say for sure if it is UL or not as their is no requirement, but I seriously doubt a Telco would allow anything that was not or at least met TELCORDIA standards.
 

GoldDigger

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Location
Placerville, CA, USA
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I have been in TELCO some 30+ years and have never known any protector or equipment installed in the customer premisses that was not UL.

As for what goes in the actual telephone switch office and cable pedestals are quite robust and heavy duty more so than what you can find in customer premisses equipment. I certainly cannot say for sure if it is UL or not as their is no requirement, but I seriously doubt a Telco would allow anything that was not or at least met TELCORDIA standards.
Thank you for that knowledge from experience.

BTW, I know that I would not be comfortable trying to handle the termination of a 100 pair cable with just the knowledge and experience I have, so I do not expect a general purpose electrician to be much better. An IT guy, maybe, if a telecomm guy is not available. :?
 

SparkyRules

Member
Location
United States
And, for weressl, these are UL listed. The phone company may or may not be required to use UL-listed products only, but the OP certainly is. This is communications wiring, not telco wiring if the telco does not install and maintain it.

There was a thread on exactly that subject (except maybe a 50-pair cable) here about a month ago.

1) They already have a Fiber going between the 2 buildings, so me thinks this is for other needs they have, security system etc
2) Yes we did spec outdoor cable (UV resistant) , there is an existing messenger wire (holding the fiber) that we can use.
 
1) 2) Yes we did spec outdoor cable (UV resistant) , there is an existing messenger wire (holding the fiber) that we can use.

Keep in mind that UV resistant cable isn't really meant for running through the air. It has a jacket that is just a bit more tolerant to runs that are exposed to weather, for example when tacked along the outside wall of a building.

ALPETH cable (ALuminum shield, PolyETHylene) cable, typically REA/RUS type PE22 is what should be used in this instance when lashed to a support member. Of course, the sheath will need to be bonded to the protected entrance terminals, but they have an integral #6 bonding stub installed at the factory for this purpose. All that you will need is the appropriate sheath bond clamps.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
1) They already have a Fiber going between the 2 buildings, so me thinks this is for other needs they have, security system etc
2) Yes we did spec outdoor cable (UV resistant) , there is an existing messenger wire (holding the fiber) that we can use.

What Ed said.:thumbsup: You also do need to know what the cable will be used for because you do have some choice in conductor sizes as well as what protectors you need. 100 pair is a bit much for security, I'm thinking more for phone extensions. How long is it? Also I know you said there is existing aerial fiber (lashed?) to a messenger. What is the messenger and what size is it?

-Hal
 
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