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## Re: Topband: OT - Bonding Radials at Intersections

 To: topband@contesting.com Re: Topband: OT - Bonding Radials at Intersections Jeff Blaine Fri, 6 Nov 2020 23:43:25 -0600
 I of course defer to Frank's expertise here.  But after thinking about this for a couple of hours, I'm trying to wrap my head around this arc risk concept as well.  It's interesting and I toss this comment out because my two sets of 4sq don't have a single cross-bonded wire anywhere - all the ground structure is ground mounted, with overlapping wires literally all over the place.  And despite that, the do seem to work more or less OK, as far as I can tell. ``` ```I guess my thinking is list this...  All those radial wires are laying out on the ground.  So they are at least connected at some point, at a DC level, assuming your talking about something conventional like a 4SQ. ``` ```Of course, we are talking about AC here, so I will agree that maybe the conditions could exist where - with just the right configuration between the two radials - that some larger than expected voltage differential may be present.  Given how low Q a 4SQ is, how current is split between multiple elements, my gut feeling is that the excitation voltages are pretty mild even if you have your 1500W source right there at the 4SQ input. ``` ```And on top of that, the wires are laying on the ground, right? The radials are in more or less intimate contact with the ground, so I would expect there to exist leakage resistance between adjacent conductors (if they are bare).  And if they are perfectly insulated, this being AC, that means there is going to be some amount of cap coupling between adjacent wires and to the ground. With all of that R&C spread out all over the field, I would certainly think this conspires to work against the probability that any two optimally aligned individual crossing conductors would provide a condition sufficient to support an arc, and that if so, it would survive long enough to cause a fire. ``` ```It's very very very dry here in the summer and again in the winter.  So fire risk is something we keep a real close eye on. Then again, out here in the Midwest some of us do a lot of IL-advised things because they seem to work and of course because laziness is a BIG part of the calculation.  ha ha.  Maybe we have been taking a walk on the wild side without realizing it.  Hope not because I sure don't want to go try to rectify this poor decision 3 years post installation!  Say it ain't so! ``` 73/jeff/ac0c alpha-charlie-zero-charlie www.ac0c.com On 11/6/20 10:59 PM, donovanf@erols.com wrote: ``````Always beware of any communication that begins "with all due respect" ----- Original Message ----- From: "Wes" To: topband@contesting.com Sent: Saturday, November 7, 2020 4:49:23 AM Subject: Re: Topband: OT - Bonding Radials at Intersections With all due respect, I must ask, how many megawatts are you guys running? Wes N7WS On 11/6/2020 3:26 PM, donovanf@erols.com wrote: ``````Hi Carl, If the insulation breaks down they will arc, potentially causing a fire 73 Frank W3LPL On 11/6/2020 4:27 PM, Richard (Rick) Karlquist wrote: ``````On 11/6/2020 1:10 PM, Carl Clawson wrote: ``````Frank, “Must” is a strong word. What goes wrong if you cross them? 73, Carl WS7L ``````Also, if insulated wires are used for radials that cross over each other, is that to be treated differently than bare metal wires that cross over each other and touch so as to have electrical connectivity? Does it matter if cross over radials are soldered at the crossovers, so as to prevent parasitic "diodes". For whatever weird reason, the price of insulated wire is nearly always lower than the equivalent bare wire. And Romex sells for less than the equivalent individual wires. Rick N6RK _________________ Searchable Archives:http://www.contesting.com/_topband - Topband Reflector `````` _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector ``````_________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector ```