Hi all :) Firstly forgive any netiquette breaches here....but I'm a long time lurker who can give first hand experience of close proximity CG lightning strikes with surge arrestors and buried cables. At the mining site where I work, we run a COAX ethernet LAN which passes from the factory to the office via a 4" steel pipe, buried at a depth of approx 1.5m. Cable run underground is in the order of 10 - 15m. Being on top of a hill and surrounded by iron-rich rock, we get more than our fair share of CG strikes up here and have had two close strikes in the last 3 years that have affected the cable run. #1 Strike was approximately 1km away. Induction(?) popped both NICs and smoked the Mobo's at either end of the buried line, all other PC's (with unfiltered power then) on site were fine. We fitted Black Box (no endorsement to be implied) COAX arrestors at either end after this event. Strike #2 was a direct hit (<500m) Both surge arrestors copped the lot, but we only lost one NIC, we did however lose multitudes of other gear. $25,000 later we now have site-wide UPS. My personal machines run CorCOM surge suppressors.Two per machine, in series. We have had several CG's within 1km of the house over the years and have escaped damage. The latest was yesterday, with a strike just across the road within 150m of the power and phone lines. I lost 3 out of the 4 suppressors, but the machines are still intact. The strike was hefty enough to cause arcing in the domestic wiring, detonating a lightbulb and leaving that heady aroma of scorched electronics and ozone that says "missed you, this time". Only loss was a modem which died in my arms as I pulled the Telecom plug - Having felt the current go through as I yanked the wire, I now have relays fitted - that was one scary sensation!! Waay offtopic by now, but there's personal anecdotes for you re: lightning. Pete Lurk Mode ON ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Various authors have previously written: > 1) Within limits of reasonably feasable. Those surge-suppressor gimmicks > on sale everywhere will certainly not protect against nearby lightning > strikes. >As I said, in Auckland it is unlikely to be a problem, but I saw quite a bit >of fried gear in Indonesia - people I was working with there, pull >phones/modems and computers out of walls during electric storms for good >reason. ------------------------------------------------------------------- To remove yourself from this list, email nzlug-request@linux.net.nz with "unsubscribe" in the body of the message.
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