With the amount of metal a lot of guys have in the air (Bill, KC4PE has no
small amount - I'm literally 10 miles up the road and have ogled his
antenna farm several times. Hi, Bill!) and the number of feedlines &
control lines coming into the shack, disconnecting is simply not a viable
option.
Proper grounding is CRITICAL to a shack, not just "...stick a rod in the
ground..." as that ain't gonna cut it. That's a small start and nothing
more. The ground SYSTEM must be BONDED to the MAINS ground as well or
you're asking current from a spike of some sort to flow through your
equipment as part of its path of least resistance to ground.
One certainly should protect the power side of the equation as well.
Everything in the shack should go through a UPS or through quality surge
protection devices. Bill already linked to the excellent PolyPhaser white
papers.
I think we can all agree that Tom, W8JI seems to have this ham radio stuff
largely figured out. It's my understanding that he doesn't have equipment
trouble despite visually confirmed lightning strikes on his LARGE antenna
farm. That's because he took great pains with his installation. His
grounding page is another excellent resource, another that Bill has linked.
When I worked for a Motorola Service Center, we had to adhere to the
Motorola R56 standard for all major systems. Google it. THAT is the
station grounding/protection bible. If you get down to it, everything
metal in the shack should be bonded to ground. That ground should consist
of MANY rods driven in a ring around the shack and linked to the ring/rods
driven around the tower.
I can't quite pull off a ring, because of the location of my shack, but
I'll put every effort into getting as close to it as I can when I get my
tower installed. With all the proper protections in place, I don't
anticipate lightning issues.
Station lightning protection is a multi-pronged approach. I don't purport
to know all there is about it, but I do know that the links above and the
R56 standard are awfully good places to start.
Insurance ain't a bad idea, either. *:-)*
Matt
KK4CPS
On Sat, Sep 6, 2014 at 7:49 AM, Bill Winkis (KC4PE) <kc4pe@mindspring.com>
wrote:
> Proper Grounding....????
>
> Can we agree that a static crash/lightning/begins with a positive charge in
> Mother Earth, whether it be your Air Conditioner compressor/your vertical
> antenna/your tower/and on......so whatever is being charged must have a
> proper ground with a proper bleed off, or the charge will continue until a
> atmospherically provided path couples and then BOOM, lightning/damage to
> whatever.
>
> SO ..if one provides a proper text book ground he will have no problem to
> bleed off this charging he will have zero problem
>
> Read On...!!!!
>
> https://www.google.com/?gws_rd=ssl#q=lighning+glen+zook
>
> http://www.w8ji.com/station_ground.htm
>
> Take the time to read the below...especially PolyPhasers WHITE Papers
>
>
> http://www.smithspower.com/brands/polyphaser/services/media-library/white-pa
> pers?page=2
>
> -KC4PE
> http://www.kc4pe.com/amateurshack.htm
>
>
>
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
> Kenneth Goodwin
> Sent: Friday, September 05, 2014 3:10 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] G-2800DXA lightning damage
>
> Agree, disconnecting everything is the only reasonable means of protection.
> If your radio equipment is hooked to a power outlet and/or a computer,
> those
> connections will have to be disconnected also unless one feels confident
> enough to have the power/network/Internet/telephone connections protected.
> Near field lightning hits which are the highest probability of occurring
> for
> most nominal station configurations, will result in two common scenarios.
> They obviously induce large amounts of energy into antenna systems and such
> things as one's security system if it has long wired connection paths, e.g.
> window sensors on one loop. Near field hits will also bring the energy
> right up the ground connections as the potential level of one's land is
> raised with the hit (the reason for single point grounds). Don't rely on
> your Internet provider even if they have what looks like a protection
> device
> in the cable. They just normally ground the shield connection if cable
> Internet/TV/VOIP telephone is used. Same applies to one's telephone if
> that
> is another wired connection. Since disconnecting every secondary
> connection
> is difficult, having protection for all of those other 'connections' is
> probably the next best step. Disconnecting one's antennas/control lines is
> still desirable regardless since the probability of one's antennas
> conducting energy is > 0. One also needs to remember the impact of today's
> house insurance deductibles. Last thing I want to do with my house
> insurance company is file a claim. It's why I use the ARRL Insurance
> program for my most expensive radio equipment. For my secondary
> connections, I use multiple UPS's for power, have a gas discharge device in
> my Comcast cable as it enters the house in addition to protection at the
> network box interface. My TV/Internet cable runs above ground except for
> the connection from the pole to the house where it runs underground as is
> normally implemented by most cable companies. In the newer neighborhoods,
> underground utilities are worth every indirect penny it costs. I use surge
> protection for the AC power at the breaker box and telephone line
> protection
> (MOVs) at the line entrance to the house. I tried protecting the AC power
> at the pole but the electric company didn't like that even though I own the
> underground wire from the breaker box to the pole. They rightfully demand
> control for everything from the power meter back. I know I can't fool
> Mother Nature even with my single point ground system since I have so many
> back doors. I realize the commercial people are able to do it, but they
> start out with a fresh sheet of paper and can easily design adequate
> lightning protection from the very beginning with a no exception single
> point ground system. Ken K5RG
>
> ------------------------------
>
> Message: 5
> Date: Fri, 05 Sep 2014 07:40:21 -0600
> From: Steve London <n2icarrl@gmail.com>
> To: towertalk@contesting.com
> Subject: [TowerTalk] G-2800DXA lightning damage
>
>
> >I live in an area with high monsoon thunderstorm activity. I doubt that
> >any
> of the protection devices would > survive. I disconnect everything where it
> enters my radio shack.
>
> >Spencer W1GAK
>
> I live near Spencer, and 100% concur with his recommendation. Put a Jones
> plug at the control box and keep it disconnected during the thunderstorm
> season unless you are actually on-the-air. If you are using a computer
> connection to the control box, disconnect that also.
>
> 73,
> Steve, N2IC
>
> _______________________________________________
>
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