I think Steve's account of the lightning damage is clear, very logical and
detailed. Case and point: disconnected antennas is not adequate. One must
disconnect the ground and the AC line too. From his description it reads as
though this was pretty much a direct strike. As I said before, to handle
that much current it would take a conductor the size of a truck.
In one project to which I was affiliated related to lightning damage
control, we measured some 6000 volts between the bottom and top of a
standard 7 ft Bud equipment cabinet during one strike. This equated to some
120,000 amps or roughly 720 megawatts of energy. There were several new
holes in the cabinet after the strike. Thank goodness for remote
instrumentation. I don't think the engineer and his trusty Simpson 260 VOM
would have survived.
Just be sure that all grounds and ground sources on the property are
connected together.
73
Bob, K4TAX
----- Original Message -----
From: "Bill Rowlett" <kc4atu@hotmail.com>
To: <tentec@contesting.com>
Sent: Saturday, November 19, 2005 4:23 PM
Subject: Re: [TenTec] Orion 2 lightning rule
> Rule #3: UNPLUG the power supply/power strip when not in use during the
> storm months.
>
>
> kc4atu
>
>
>>From: "Stephen M. Shearer" <wb3lgc@verizon.net>
>>Reply-To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
>>To: "'Discussion of Ten-Tec Equipment'" <tentec@contesting.com>
>>Subject: Re: [TenTec] Orion 2 lightning rule
>>Date: Sat, 19 Nov 2005 12:33:04 -0500
>>
>>You asked: This is what I supplied to the insurance companies (note ARRL
>>insurance was purchased 6 days before the strike). I was at the BSA
>>Jamboree at the time. My wife and cat were at home at 5am when the strike
>>hit. I had two (2) leaks in the gas stove. One was a 1/32" hole in the
>>flex gas line.
>>
>>DETAIL of Lightning Strike:
>>
>>The lightning strike hit the center [actually one end] of the WB3LGC/G5RV
>>antenna in the back yard and vaporized the ladder line feeding both sides
>>of
>>the antenna [the steel copperweld wire was vaporized, but left the plastic
>>jacket]. The lightning followed the coax cable to the free end of the
>>cable
>>in the basement shop/radio shack. On the way to the basement, the
>>lightning
>>took a side trip [blew a hole in the coax and house] to the power/circuit
>>panel, via the house wiring. This same discharge path also found the
>>underground cables feeding the detached garage. The circuit panel had
>>breakers tripped for the kitchen and the bathroom. One likely discharge
>>path, via the ground wire in the romex cable, is the kitchen circuit
>>feeding
>>the stove and the path to ground via the black pipe gas line. This could
>>[did] account for the small gas leak at the stove. In the basement, the
>>lightning discharged through a metal workbench with a metal top [the coax
>>was on the concrete floor]. A portable TV on top of the bench became
>>fried
>>[a number of holes zapped in the bench] and the major source of smoke that
>>set off the smoke detector in the shop and at the top of the basement
>>stairs. The TV and everything that was plugged into the common power
>>strip
>>also became "toast". The power strip fed both UPS's, a wireless
>>telephone,
>>a power supply for the Orion radio, a computer and monitor [replaced with
>>a
>>nice laptop]. The final path was through the heavy ground strap attached
>>to
>>the Orion radio to the 5/8" copper water line feed for the house. The
>>phone
>>line in the basement is a direct feed to the office computer on the second
>>floor.
>>
>>73, Steve WB3LGC
>>The Orion took its hit via the 12V power line and the case (jumping from
>>the
>>workbench to the UPS to the Orion). New Lightning Rule #2; Ground the
>>un-used coax in the shack or before it gets to the shack [it might have
>>helped].
>>
>>-----Original Message-----
>>From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
>>On Behalf Of Peter Burbank
>>Sent: Saturday, November 19, 2005 11:53 AM
>>To: Discussion of Ten-Tec Equipment; 'Discussion of Ten-Tec Equipment'
>>Subject: Re: [TenTec] Orion 2 lightning rule
>>
>>
>> >
>> >Btw: New Lightning Rule #1; A well grounded rig will provide a path for
>> >lightning even if the antenna coax is disconnected from (and separated
>>from)
>> >the radio.
>> >
>> >73, Steve WB3LGC
>>
>>Steve, have you been able to trace the lightning path or any particular
>>reason why
>>it hit your rig?
>>73 Pete NV4V
>>
>>
>>--
>>No virus found in this outgoing message.
>>Checked by AVG Anti-Virus.
>>Version: 7.1.362 / Virus Database: 267.13.4/175 - Release Date: 11/18/2005
>>
>>
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