TenTec
[Top] [All Lists]

Re: [TenTec] Grounding manual for Hams

To: Clayton Brantley <clayton_n4ev@yahoo.com>, Discussion of Ten-Tec Equipment <tentec@contesting.com>
Subject: Re: [TenTec] Grounding manual for Hams
From: Reed Krenn <reed.krenn@gmail.com>
Reply-to: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Date: Sun, 18 May 2014 18:32:27 -0400
List-post: <tentec@contesting.com">mailto:tentec@contesting.com>
Add to the list the AT&T Technical Practice TP-76300. Put TP-76300 into
your search engine and there are numerous sources for the document. Section
H covers Grounding and Bonding, and there are subsections specific to radio
base stations. These are the practices used to protect cell sites, which
are lightning attractors of the highest order!

Reed / WW3A


On Sun, May 18, 2014 at 6:07 PM, Clayton Brantley via TenTec <
tentec@contesting.com> wrote:

> Gentlemen,  There was a mention about writing a book about lightning
> protection.  Well the
> compendium has already been written and just needs to be brought to
> light.  Using an old
> Navy term, ZUI (Your attention is called to ...) I would like to list a
> few of the manuals that
> have been around for years:
>
>     "Fundamental Considerations of Lightning Protection, Grounding,
> Bonding and Shielding"
>     Federal Aviation  Administration, Washington, DC, July 28, 1978
>
>     Block, Roger R., The 'Grounds' for Lightning and EMP Protection, Poly
> Phaser, 1425
>     Industrial Way, Gardnerville, NV 89410-1237, 1987
>
>     IEEE Standard 587-1980. "Surge Voltages in AC Power Circuits."
>
>     FCC Part 68, "Connecting to the Telephone Network."
>
>     Bodie, David, Electrical Protection Guide for Land-based Radio
> Facilities, Joslyn Electronic
>     Systems, Santa Barbara Research Park, PO Box 817, Goleta, CA 93017,
> March 1976
>
> These are a few of the books and articles available.  I would encourage
> your reading a few of
> them.  Will make for a safer place to enjoy our hobby.
>
> Clayton N4EV
>
>
> On Sunday, May 18, 2014 10:30 AM, Jim Allen <jim.allen@longhornband.net>
> wrote:
>
>
>
> I made the mistake of peering into the Code not long ago.  If you are not a
> technical person, an engineer say, it might as well have been written in an
> obscure dialect of Urdu.
>
> I then made the further mistake of discussing my grounding idea with my
> electrician who installed the electrical service in the outbuilding now
> known as my shack.  We went round and round politely not understanding each
> other for 20 minutes or more, before he finally said he would talk to his
> suppliers in the big city and see if they had the devices he was sure were
> required that he did not stock, and seldom used but cost several hundred
> dollars and would require a seemingly massive installation process.  Or so
> I discerned from the conversation.
>
> There seems to be no uniformity of opinion about what is required, what is
> adequate, in a variety of situations hams face in planning and installing
> grounding systems, except everyone seems to agree that the old
> recommendation of connecting a large wire as short as possible to the water
> pipe outside isn't the way to go.
>
> I spent $475 installing an 8' copper clad rod in a pit 30" deep, 8' long
> and 6" side here on the Rock Ranch.  The money was spent hiring a young man
> to try to dig the pit, and renting a demo hammer from HD.  It was like
> carving the face of Mt. Rushmore, and took him 2 and a half days working
> like a rented mule.  I hope it is adequate!
>
> A volume of practical suggestions on how to approach different situations
> would be worth its weight.
>
> 73 de W6OGC  Jim Allen
>
>
> On Sun, May 18, 2014 at 9:13 AM, Cecil <chacuff@cableone.net> wrote:
>
> > But don't expect it to provide a clue as to how to build a ground system
> > for proper lightning protection...it is concerned most about electrical
> > safety grounding...important but not the all inclusive answer.
> >
> > Cecil
> >
> > Sent from my iPad
> >
> > > On May 17, 2014, at 3:24 PM, P C A <xtraham58@hotmail.com> wrote:
> > >
> > > I think everyone should start by reading the National Electrical CODE ,
> > NEC on grounding, work from there. This is in part of the National Fire
> > Prevention Association NFPA.Andy
> > >
> > >>
> > >>
> > >> Eric,
> > >>
> > >> You're the right man for the job of writing this manual.  I like the
> > >> lightening protection for a chapter, RF grounding for a second
> chapter,
> > and
> > >> a third on getting them both in sync.
> > >>
> > >> Being a sociologist by training I can appreciate the engineers
> > reputation
> > >> for being concise - so why not establish a drop box with the two
> > chapters as
> > >> a start.  Open it up to everyone for reading, you take one chapter and
> > >> another guy a second chapter - form a small team for each chapter with
> > >> access to edit and away you go?
> > >>
> > >> I'll be happy to read the drafts as a non-engineer and comment
> > accordingly.
> > >>
> > >> Kris KM2KM
> > >>
> > >> MERSCHROD
> > >> 123 Warren Road
> > >> Ithaca, NY 14850
> > >> Skype: Merschrod
> > >>
> > >> -----Original Message-----
> > >> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of R.
> > Eric
> > >> Sluder - W9WLW via TenTec
> > >> Sent: Saturday, May 17, 2014 10:36 AM
> > >> To: Discussion of Ten-Tec Equipment; Robert
> > >> Subject: Re: [TenTec] Eagle problem?
> > >>
> > >> Ya know gentlemen; I think that some of you should gather and
> contribute
> > >> your vast knowledge of grounding and lightening protection to
> establish
> > a
> > >> standards document that Hams can use.
> > >>
> > >> Imagine a standard that all Hams could reference that has been vetted
> by
> > >> those who's credentials and industry experience provide a truly usable
> > and
> > >> safe reference for all.
> > >>
> > >> A lot of what I read is accurate, but some of it is questionable in my
> > mind
> > >> based on my industry training and experience in telecommunications and
> > now
> > >> hospital building construction.  I've used IEEE, BICSI, TIA, ANSI, NEC
> > and
> > >> other similar references and they all collide at some point in the way
> > to
> > >> provide ground (earth) and lightning protection.  I share all that
> > because
> > >> this debate has me confused at different points, and I can't imagine
> > how the
> > >> humble Ham who's a Dentist, truck driver or whatever their profession
> > is -
> > >> try to follow along and gain a general understanding of grounding and
> > >> lightening protection (two different disciplines with commonality).
> > >>
> > >> We all could benefit (and save our stations) by some of you really
> > smart and
> > >> well versed chaps gathering and hammering out a standard we could all
> > live
> > >> and operate by.
> > >>
> > >> Be well, operate safely during the storm season and save your loose
> > change
> > >> for a Patriot.  Jim Whalton gave me the run down yesterday at the TT
> > >> booth... it looks like fun.
> > >>
> > >> 73 - Eric
> > >> W9WLW
> > >>
> > >> On May 16, 2014 7:47:03 PM EDT, Robert <rmcgraw@blomand.net> wrote:
> > >> |I had 3 pieces of 1" braid in place to bond the rotating mast to the
> > >> |sleeve at the top of my tower.   A lightning strike burned all 3
> into.
> > >> |Balled ends on the strands confirmed this.
> > >> |
> > >> |73
> > >> |Bob
> > >> |
> > >> |
> > >> |Sent from my iPhone
> > >> |
> > >> |> On May 16, 2014, at 6:04 PM, Stuart Rohre <rohre@arlut.utexas.edu>
> > >> |wrote:
> > >> |>
> > >> |> Jim, don't we all use Flukes now?  :-)  I do have several at home
> and
> > >> |work.  I was remembering a discussion of a rig fault where the pin
> > >> |intended for grounding, had not been grounded at the radio connector
> > >> |entry to chassis.
> > >> |>
> > >> |> Good point you make about low ranges needed for ohms measuring.
> > >> |There are some good build it yourself low ohms measuring circuits out
> > >> |there, to extend the range of an ordinary meter.  The Graf (author)
> > >> |series of circuit diagrams books includes at least one.  The ham
> > >> |magazines in last 40 years had one or more.
> > >> |>
> > >> |> In the midst of measuring things, most good troubleshooting
> includes
> > >> |a thorough visual inspection to see how things are bonded and
> grounded,
> > >> |and if the circuit board is providing the connection to chassis.
> > >> |> Unfortunately, we had not done a pre service inspection of the
> > >> |following radio incident:
> > >> |>
> > >> |> For high current faults, we have seen a Yaesu 5100 that had RF
> > >> |connection to circuit board and its DC negative power line to same
> > >> |circuit board at other end of chassis.  A lightning event on the
> tower
> > >> |induced shield current down the coax to the radio , across the
> circuit
> > >> |board, vaporizing part of the ground copper, and then to the DC
> > >> |negative line which returned to AC third pin and power supply
> chassis.
> > >> |>
> > >> |> The bonding was done by an experienced power plant engineer, but it
> > >> |provided an extra return path through that circuit board trace, that
> > >> |caused severe damage to the trace.  Luckily, that radio has survived
> > >> |that, with a bus bar now bonding DC negative to the coax connector
> > >> |shell external to the chassis.  (No longer relying on the radio
> circuit
> > >> |board traces.)  The radio worked even after losing part of the board
> > >> |copper, but only if the coax was connected, which was grounded to the
> > >> |tower and earth providing a return through the AC third pin.  That
> > >> |observation prompted us to open the radio, which then showed the
> > >> |missing trace.
> > >> |>
> > >> |> As for braid failures, literature about high current faults has
> > >> |stated that braid can blow apart in a near direct strike, as little
> > >> |shards of wire.  Indoors in someone's shack that could cause injury,
> or
> > >> |put small shorts into places hard to find.
> > >> |>
> > >> |> Copper flashing could be used in place of braid.  The use or either
> > >> |was to provide low inductance through wide flat conductors used for
> > >> |bonding equipment together.
> > >> |>
> > >> |> Stuart Rohre
> > >> |> K5KVH
> > >> |> _______________________________________________
> > >> |> TenTec mailing list
> > >> |> TenTec@contesting.com
> > >> |> http://lists.contesting.com/mailman/listinfo/tentec
> > >> |_______________________________________________
> > >> |TenTec mailing list
> > >> |TenTec@contesting.com
> > >> |http://lists.contesting.com/mailman/listinfo/tentec
> > >>
> > >> --
> > >> Sent from my Android device with K-9 Mail. Please excuse my brevity.
>
> > >> _______________________________________________
> > >> TenTec mailing list
> > >> TenTec@contesting.com
> > >> http://lists.contesting.com/mailman/listinfo/tentec
> > >>
> > >> _______________________________________________
> > >> TenTec mailing list
> > >> TenTec@contesting.com
> > >> http://lists.contesting.com/mailman/listinfo/tentec
> > >
> > > _______________________________________________
> > > TenTec mailing list
> > > TenTec@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/tentec
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec

<Prev in Thread] Current Thread [Next in Thread>