Im laying out the ground rod scheme for the towers. As I look at Mot R56, it seems like about 45 of rods gets you to the 5 ohm target based on one of the graphics they provide Thats about 9 ground ro
Simple answer... you can't. There is an Appendix in R56 that details how you measure your system to insure you meet whatever standard you set for yourself. It would appear that the equipment for the
As I look at Mot R56, it seems like about 45 of rods gets you to the 5 ohm target based on one of the graphics they provide Thats about 9 ground rods spread out in 3 legs each with 3 rods separated b
Jeff, You install ground rods until either your back hurts, your wallet hurts, or both. I have six 'strings' of four rods each for a total of 24 rods per tower. Installed them 16 feet apart, in a on
How is ground resistance measured? John KK9A "The contractor shall install sufficient ground rods in accordance with document XYZ that the measured ground resistance is less than 5 ohms." At the end
I think R56 says one 8 rod per 16 out to height of tower. Sent from my iPhone _______________________________________________ _______________________________________________ TowerTalk mailing list To
Most likely your back and wallet will both hurt however it is really worth the effort to follow the guidelines. John KK9A Jeff, You install ground rods until either your back hurts, your wallet hurts
With an AC ohmmeter specifically designed for this application. Mostly, it's a matter of standard probes, standard measuring voltages and currents, etc. so that everyone's measurements are the same.
In one of the Polyphaser documents they talk about the rise time and length of a strike duration. Forget the details but the conclusion was that rods further out than about 50' would not be effective
Jim Lux's post on this cuts to the heart of the issue -- it's impedance that matters most, and that's dominated by inductance, not resistance. And yes, the contribution of those rods farther from th
I am intending to have two circles of ground rods (ten foot) around my towers. One question as I look at the thotos supplied by K9YC is whether to use solid or stranded ground wire. Is there a prefer
Mmmmm.... the speed of light is REALLY REALLY REALLY fast... The speed of current through big copper is still REALLY fast... 50 feet? Nah.... Rise time and duration for WHICH part of the strike e
If that's true then it seems there is an implied maximum density of the field based on the 50' maximum radius for rods and the 2x rod length spacing. Its a bit more complex than that.. you've got wha
In regards to " Mot R36 related to NUMBER of installed ground rods" I've done a quick search and have a question. What, exactly is " Mot R36" as related to NUMBER of installed ground rods ? I was alw
Not only is it very slow propagation, but it is very lossy propagation as there are streamers and corona and all sorts of other ugly things going on underground along a radial. When I measured the ve
the speed is slower than you think.. one way is to think of it as a wire immersed in a dielectric, for which the speed will be sqrt(epsilon).. if you use the ham favorite of 5/13 soil, sqrt(13) is 3
A "ground resistance meter" (of course ;) ). As for most instruments the US brand electricians meters are pricey, think $1k and up. I found a clamp on style on ebay. Clamp ons are super easy to use.
Reply inline.... On 11/3/2017 2:21 PM, jimlux wrote: the speed is slower than you think.. one way is to think of it as a wire immersed in a dielectric, for which the speed will be sqrt(epsilon).. if
I see how this works now, thanks. Since it takes specialized equipment, I wonder how many hams actually test their ground rods. John KK9A With an AC ohmmeter specifically designed for this applicatio
This might be of interest. www.electricalpartmanuals.com/pdf/miscellaneous/Biddle%20Instruments/.../25TA.pdf On 11/3/2017 5:14 AM, Clay Autery wrote: Simple answer... you can't. There is an Appendix