The glass is formed from the sand around the rod getting to the melting
point.
73
Gary K4FMX
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
> Hans Hammarquist via TowerTalk
> Sent: Thursday, January 14, 2016 5:17 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Fwd: Fwd: Fwd: The Need for Grounding
>
> kelly,
>
>
> I don't really understand your question. "boundless"? I, myself, was
> more into overdoing it rather than underdoing it and later found out "it
> was to little. I have 9 grounding rods around my tower. Three
> conductors, one to each rod, will also have lower inductance than only
> one conductor.
>
>
> My shack is also shielded by and this shield is connected to the tower
> with a 6 inch wide aluminum band. My idea is that at a lightning strike
> in the tower (or anywhere else that affect the installation), the
> voltage difference between the tower and the shack is minimized and
> thereby limiting damages inside the shack.
>
>
> It might be possible that one grounding rod is OK but I will not take
> that chance. If you, on top of that believe that a grounding rod can be
> "overloaded" you will use more than one.
>
>
> I still don't know is a layer of glass can form around a rod in case of
> "overload". Anybody knows?
>
>
> Hans - N2JFS
>
>
>
> -----Original Message-----
> From: Kelly Taylor <ve4xt@mymts.net>
> To: Hans Hammarquist <hanslg@aol.com>
> Sent: Thu, Jan 14, 2016 2:20 pm
> Subject: Re: [TowerTalk] Fwd: Fwd: The Need for Grounding
>
> Hi Hans,
>
> If the capacity of a single rod was boundless, there wouldn't be a need
> for more than one, yes?
>
> 73, Kelly
> ve4xt
>
> Sent from my iPhone
>
> > On Jan 14, 2016, at 1:13 PM, Hans Hammarquist via TowerTalk
> <towertalk@contesting.com> wrote:
> >
> >
> >
> > No, the current does not follow "the shortest path". Yes, my mother
> always said that but Ohms' law predict more accurately how the current
> divide. More current will go through a lower resistant/ high conductive
> path but there will be current going through any conductive path, high
> or low.
> >
> >
> > Keep in mind that due to ionization conductivity can change during a
> lightning event. The current will even follow paths generated directly
> through air. I guess you might also experience where grounding rods get
> insulated from ground due to the glazing effect due to the very high
> current density and following high temperature. I don't know if this
> ever happens but like to hear if anybody knows.
> >
> >
> > All the above events will lead to the unpredictable path of lightning
> damages.
> >
> >
> > An other phenomena you might encounter is, if you are present at the
> lightning event, that the lightning flashes seen, do not necessary occur
> at that point the observer claim they saw them. This is something I
> experienced my self.
> >
> >
> > Best 73 de,
> >
> >
> > Hans - N2JFS
> >
> >
> >
> >
> >
> > -----Original Message-----
> > From: Kelly Taylor <ve4xt@mymts.net>
> > To: Edward McCann <edwmccann@yahoo.com>
> > Cc: Bryan Swadener via TowerTalk <towertalk@contesting.com>; Hans
> Hammarquist <hanslg@aol.com>
> > Sent: Thu, Jan 14, 2016 12:24 pm
> > Subject: Re: [TowerTalk] Fwd: The Need for Grounding
> >
> > The important thing to remember is electricity doesn't follow the
> shortest path somewhere, it follows the path of least resistance. And
> it's important to point out that during a lightning event, that path is
> going to change, as the lightning charge will easily overload a single
> rod, driving that rod's resistance sky high. Since the event is not yet
> over, the remaining charge will follow the next-best path, which could
> be through your radio. Better it be through the other rods in your
> network, no?Is it useful to envision ground rods as resistors, and a
> chain of ground rods as resistors in parallel?Since we all know parallel
> resistors divide current among them, and as a group present a resistance
> that is some fraction of their individual values, is it a good meme to
> remind us of the importance of multiple rods?73, kellyve4xt> On Jan 14,
> 2016, at 10:35 AM, Edward McCann via TowerTalk
> <towertalk@contesting.com> wrote:> > On point.> It is unlikely Ohm's Law
> will ever be repealed,> by the current crew in the beltway or that if
> the pretenders to the throne.> AG6CX> > Sent from my iPhone> >> On Jan
> 14, 2016, at 8:22 AM, Hans Hammarquist via TowerTalk
> <towertalk@contesting.com> wrote:>> >> It's simply Ohm's law that still
> is valid. Yes, voltage across all the inductance adds in too.>> >> >> In
> my case, my tower is grounded with a resistance to ground of about 3
> ohms (when it was tested some time ago). If the tower is hit, (I guess)
> the current is about 3 kA with a resulting 9 kV between the tower and
> ground.
> >
> > _______________________________________________
> >
> >
> >
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