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#160611 - 01/20/07 01:56 PM Lighying Protection for DSL
Obsaleet Offline

Registered: 04/05/03
Posts: 361
Loc: Pa
Hi all,
Cumputer guy I do work for would like to Protect his DSL from lightning. Can this be done and how?

Choose your customers, don't let them choose you.

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#160612 - 01/20/07 07:09 PM Re: Lighying Protection for DSL
BuildingHomes Offline

Registered: 11/19/06
Posts: 18
Loc: Burlington, Ontario, CANADA
There are many power bars out there that have an RJ jack in them to pass through and offer some form of surge protection.. But the only reliable way to protect against lightning is to create a nice physical gap.. unplug it.

#160613 - 01/20/07 07:21 PM Re: Lighying Protection for DSL
gfretwell Offline


Registered: 07/20/04
Posts: 9025
Loc: Estero,Fl,usa
"Unplug it" is not really an option if it storms very often.
Start with verifying that the Telco has a modern Dmark with gas protectors and that it is tied to your service ground electrode system. Then use a point of use protector where the DSL modem plugs in that catches the phone and power. You should already have a panel protector if it ever storms there.
I suspect the telco is as interested in protecting their modem as much as you are.
That will be ground zero if there is a strike. I know when I had DSL installed they gave me a new Dmark and a fatter ground wire to my existing ground rod(s).
Greg Fretwell

#160614 - 01/22/07 05:02 PM Re: Lighying Protection for DSL
LK Offline


Registered: 01/21/03
Posts: 1721
Loc: New Jersey
"only reliable way to protect against lightning is to create a nice physical gap.. unplug it."

Disconnecting it, allows a charged enviroment to build up, with no means of discharge, discharge connectors or blocks, at point of entry, is where they are required.

If there was a near strike, the disconnected equipment would most likely be the first to take a hit.

#160615 - 01/22/07 08:42 PM Re: Lighying Protection for DSL
BuildingHomes Offline

Registered: 11/19/06
Posts: 18
Loc: Burlington, Ontario, CANADA
So you mean if something is unplugged completely, sitting dead, that if lightning strikes your service, that unplugged item is also toast?

Please correct me if I am wrong.. I have lots of nice electronic stuff that I would like to keep.

#160616 - 01/24/07 07:15 PM Re: Lighying Protection for DSL
techie Offline

Registered: 05/17/05
Posts: 240
Loc: palo alto, ca usa
One of the trick with lightning is making sure that all protection is tied to the same ground, so that no difference in potential exists between grounds. Make sure that the telephone, catv, electrical, satellite, and any other grounds all tie to the same place, and that all grounds are properly tied together to form a complete grounding system.

The concept is that a lightning strike is going to raise the ground potential of the surrounding area, and that by having all ground tied together as a complete system, you attempt to eliminate the differential between grounding points.

By typing all the grounds together at the perimeter, you attempt to keep the lightning from entering the structure in search of a better ground.

Make sure that all services are properly protected by lightning arresters at the service entrance. polyphaser makes high grade lightning arresters, as do others. has some more info.
Motorola has a manual on site grounding for communications sites, known as the R56 standards and guidelines for communications sites, which contains a useful section of grounding.

[This message has been edited by techie (edited 01-24-2007).]

#160617 - 01/25/07 06:07 PM Re: Lighying Protection for DSL
wrichey Offline
Junior Member

Registered: 12/19/06
Posts: 3
Loc: South Texas
ITW Links makes great electronic protection. The primary from the nid is ok but you will need secondary. Make sure you connect the ground on the secondary to the known good ground or you will not have a loop. If you dont know were that is just follow the nid ground.

Oh and a 170 volt self resetting clamp is ideal.
R&W Commuications LLC


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