[TowerTalk] Lightning Protection Components

Scott Bullock twoway@scoden.ma.ultranet.com
Thu, 10 Apr 1997 11:53:30 -0400 (EDT)


>K4VUD wrote: 
>>Do not bother with arresters, pill plugs devices, or whatever. 
>>Just unhook it all! 
>
>Wendell, I disagree with the above statement (no flame, just disagree).  If 
>all you do is unhook cables, even if it is at the point of entry, you've done 
>nothing to protect your site from a lightning strike.  You still need to 
>provide a path to ground.  Preferably the single point ground you described 
>Wendell.  Without a good path to ground, the current will select the nearest 
>object to jump to!  Maybe it'll jump to your expensive equipment "isolated" on 
>your operating bench. 
>


I totally agree with this philosophy-If you just disconnect the cable, you
are still leaving yourself open to equipment damage. In the two way
communications field, I have probably seen 30 sites with damaged equipment
in the past 15 years,some of it with very complex grounding apparatus. After
seeing what a direct strike can do to equipment/cables/racks,etc, you
develope a healthy respect for it!


 
>You should use a grounded switch like Alpha Delta makes or an IEC or 
>PolyPhaser protector.  But do something.  Don't just unplug the cables.  I use 
>both a ground switch at my grounded entry window and a PolyPhaser protector on 
>each cable going to the shack.  And during storm season (April-September) I 
>also unplug the cables going into the shack in the next room.  I do this each 
>time I quit operating.  Now equipment is isolated (next room) and everything 
>is properly grounded protecting my family and property. 
> 

Absolutely-ALWAYS disconnect and ground the disconnected cables-the lowest
impedance to ground minimizes any possible damage.

>I only unplug the power cable when a storm is VERY near.  I figure that's what 
>my ISOBAR surge protector and home insurance is for.  I don't usually have 
>time to run around unplugging everything AC powered in my house because I'm 
>usually on my way out to a NWS watch point with the 2meter rig in hand.  You 
>do volunteer with ARES don't you??  After all, ya can't DX during a storm! 
>

When at all possible unplug all equipment, and keep the cords as far away as
possible from the outlet. About 20 years ago when I was first licensed, I
was sitting in my shack with all the equipment disconnected, when the house
diagonal to and in back of ours was hit directly-house caught on fire
instantly, and the lightning split in a zillion bolts-I had a bolt of
lightning come out of the electric socket and arc to my arm from 6 feet
away-It was the SCARIEST thing you could ever imagine! At the same time, a
neighbor was walking his dog-one of the fingers hit his metal dog chain,
killed the dog instantly, and paralyzed his arm for almost 2 days!
 
So do you still think it's ok to just disconnect cables??

73,
Scott 
KA1CLX


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