On Thursday 13 December 2007, Tim wrote: >On Thu, 2007-12-13 at 16:21 +0000, Chris G wrote: >> in reality ordinary cable will survive some years outdoors. >> Depends on its coloring. Clear 300 ohm poly tv wire had a usable life of about a year, brown and black copies of the same often last 10+ years. >> I had some old-fashioned "thin ethernet" running out of the window and >> over the flat roof of my garage at my old house for several years. I >> removed it when we moved house and it was in perfectly serviceable >> condition still. > >I've found variable results. Some goes rigid and inflexible after >exposure, and will crack if you flex it. For coax, the outer cover is >part of the characterisics of the cable, if that chemically deteriorates >it can affect performance (e.g. becomes permeable to water). Not that >I'd expect to see trouble from ethernet use, but perhaps for comms. And I have a piece of Beldens bright blue cat5 stretched between phone line style strain reliefs for about 40 feet between my house and my workshop, hanging in the sun and blowing in the wind for nearly 5 years now. Its sagging just enough the top of the shop door drags on it now, but is otherwise as good as the day I hung it 4.5 years ago. It won't surprise me when I have to replace it, but I am surprised its lasted as well as it has too. That sag represents an overall stretch of at least a foot, probably closer to 2 feet over that 40 feet in that time frame. >> If there's a choice dark colours are likely to be better in a very >> sun-exposed position than light colours. > >I would have thought otherwise, but that seems the conventional wisdom. >Black will absorb more heat and cook itself in the sun, other things can >reflect it away much better. Though is seems usual that the chemicals >in black plastic are more stable. > They absorb the damaging ultraviolet in the sunlight at the surface, whereas the clearer colored stuffs lets in get all the way through the plastic. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) To err is human, to forgive unusual.
