sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Using CAT5 outside...

I recently read some dire warnings about the dangers (i.e. lightning) of using CAT5 on the outside of a building.

Now, I realise that regular old CAT5 wasn't designed to be used in an outdoor environment. But I know that people often use it outdoors anyway (although of course not in any professional installation!). Most of the phone lines in my house are CAT5 wrapped around the exterior of the building (done by a previous tenant, not me!)

What I can't understand is what I'm hearing about the (apparently extensive) lightning danger of this practice. Why would CAT5 be any more susceptible to being struck by lightning than anything else on the outside of a building?

Let's say lightning struck the coax on the outside of my house. Directly. Sure, there's a ground at the demarcation point, but is that going to make much difference if a bolt of lightning directly strikes the cable right on the side of my home?

I think they are talking data ,they shouldn't be anymore acceptable to lightning , but computers are more suseptible to static ,and more costly to replace ,There is direct buried Cat5 ,and lightning prtectors for Cat 5 also.

The ground at the demarcation is there just for that reason. If lightining strikes it will travel to the point of least resistance through the ground wire, wich will discharge the energy. Therefore any outdoor cable has to be grounded for a proper installation.