Hi Gary,
The data sheets for these GDTs provide some info about expected life.
For example, the light duty GDTs that I gave the link for says that they are
designed for 300 impulse operations at 100A, but only one operation at 10,000A.
Data sheet here:
https://www.mouser.ca/datasheet/2/54/2057-66485.pdf
There are other, more robust GDTs, some of which I have used that have even
higher dissipation values. It is worth reviewing the data sheets on various
units to find one best suited to your needs. Perhaps in lighting prone
Florida, a more robust device is called for.
I have not had any failures here, and do see lightning frequently during our
summer months with convective thunderstorms from daytime heating.
Steve, Ve6wz.
Sent from my iPad
> On Apr 16, 2023, at 8:22 PM, Gary K9GS <k9gs@gjschwartz.com> wrote:
>
>
> Hi Steve,
>
> Curious, how do you determine when the GDT has been degraded, from repeated
> discharges, to require replacement?
>
>
>
> 73,
>
> Gary K9GS
>
>
> -------- Original message --------
> From: steve_VE6WZ <ve6wz@shaw.ca>
> Date: 4/16/23 10:43 PM (GMT-05:00)
> To: RVZ <rlvz@aol.com>, towertalk@contesting.com
> Subject: Re: [TowerTalk] Beverage Resistor Source- Thank You!
>
> Hi Dick,
>
> As others have said, also add a GDT across the Beverage feed box, between
> antenna and gnd.
> Adding another across the coax at the feed box is good prevention too.
> This will prevent vaporizing the matching transformer.
>
> Buy a lot of those GDTs. Anything that is exposed to a potential lightning
> surge can use one.
> I buy 100 at a time.
>
> What some may not know, is that these Gas Discharge Tubes (GDT) are exactly
> what you find inside of the coax lightning arrestors like Alpha Delta and
> others.
>
> At my remote station, ANYTHING that is outside in the field, and anything
> that enters the shack has a GDT on an exposed line. This includes all coax
> feeds and DC control lines going to boxes in the field.
> Add some at the shack entry too.
>
> A problem with using a fuse in series is that they may not react fast enough
> to protect what is down stream. A GDT is designed for this purpose. It is
> fast and designed to dissipate the energy to ground to limit damage.
>
> 73, de steve ve6wz
>
> Sent from Mail for Windows
>
> From: RVZ via TowerTalk
> Sent: April 16, 2023 8:00 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Beverage Resistor Source- Thank You!
>
> A big Thank You to everyone who replied about my Beverage Resistor question.
> Many great ideas. For starts I'm going to add a gas discharge tube between
> the beverage resistor and ground. And if that doesn't solve the problem I'll
> add a 1-Amp fuse in-line. Thanks & 73, Dick- K9OM
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