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Electric Underground Dog fence- WTF?

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Old Mar 1, 2018 | 10:19 PM
  #21  
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Out of curiosity... what are the qualifications of a professional dog fence installer? I may be looking for a career change.

bustin chops, couldn't help myself. No offense to dog fence installers, spending the day outside and leaving the office at the office has appeal.
Old Mar 1, 2018 | 10:28 PM
  #22  
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The most important part of a good solder joint is the mechanical connection between the copper conductors before you even solder it. The resistance of solder alone is like 5x greater than the resistance of the copper that it joins. If the joint moves at all while the solder is cooling, the resistance is higher still. When doing benchtop electronics I’m obsessive about lead dress, sanding the copper wire until shiny, and holding the joint stable until it’s cool. I don’t know how you did your joints, and this may not be relevant at all, but it’s a lot harder to make a really good solder joint when you’re standing and holding things with your hands. I assume that all this wire makes a big loop; all it takes is one bad joint.
Old Mar 2, 2018 | 08:53 AM
  #23  
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Originally Posted by miata2fast
Dog fencing systems live a hard life, and are very susceptible to damage. Its not worth the trouble to solder the connections. You never see the professional installers soldering the connections, and I suspect trouble with yours.
My reasoning for the solder was longevity. I have been soldering small electric for a long time now, so I dont really question my skill or the ability to spot a shitty joint. But if a good silver joint is really 5x or greater resistance than copper, well then we might have a problem, even though I used a 3rd hand tool to hold the wires. My wire is 3 feet off the ground and does not have many likely natural predators. So i was going for a 10 yr. install.


This weekend I will cut all the splices and wire nut teh damn thing. fingers crossed.
Old Mar 2, 2018 | 09:05 AM
  #24  
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Originally Posted by ryansmoneypit
(...) even though I used a 3rd hand tool to hold the wires.
The fact that you know what this tool is, and own one, makes me suspect that your solder joints don't suck.

I fully support the wire nut experiment, but I seriously question whether:

A: Silver-solder joints have 5x the resistance of some unspecified length of copper, and
B: This matters in the least.

I mean, you could argue that it creates an interesting VSWR condition in an RF system, but again, we routinely solder RF fittings in transmitter plants, and we're routinely passing 50 kilowatts through them without them melting. There are also lead-free soldered joints in the speed controllers of RC airplanes which pass hundreds of amps at just a few volts. If this was a problem, we'd know about it by now.

If you'll pardon the pun, I genuinely believe that customer support has you barking up the wrong tree here.
Old Mar 2, 2018 | 11:39 AM
  #25  
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Originally Posted by Joe Perez
I fully support the wire nut experiment, but I seriously question whether:

A: Silver-solder joints have 5x the resistance of some unspecified length of copper, and
B: This matters in the least.
To be fair, Schroedinger claimed that solder alone had 5x the resistance of copper, not that a solder-secured joint has 5x the resistance.
Old Mar 2, 2018 | 12:06 PM
  #26  
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Originally Posted by mgeoffriau
To be fair, Schroedinger claimed that solder alone had 5x the resistance of copper, not that a solder-secured joint has 5x the resistance.
I get what you're saying. To a layman, that might be construed as meaning "if you use silver-soldered joints, the resistance of the system will increase by 5x", when in reality, we're only talking about a few millimeters of total length of silver solder across the whole system (not sure how many joints there are) which, in reality, translates to "if you use silver-soldered joints, the total resistance of the system will increase by 0.0000x%"

This phenomenon is why you can get away with using 28ga jumper wire in high-current circuits, provided that the jumpers are *extremely* short.
Old Mar 2, 2018 | 09:24 PM
  #27  
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^ all true. If the joint has good wire/wire contact prior to soldering, the resistance of the solder is negligible. With sloppy work, there often isn’t good wire/wire contact. It sounds like Ryan knows what he’s doing though, so my point is probably irrelevant. However, I still think it’s possible that one or more of the solder joints isn’t great, and that could be causing the problem. I used to build and restore tube amps and consider myself pretty good with a soldering iron, and I’m pretty sure that every amp I ever built had at least one bad joint that I had to revise. And that’s on a benchtop with good light and good tools. Apropos of nothing and just because I’m sitting right in front of them, I rescued all three of these little beauties from the trash.




Wire nuts are not my favorite, especially with stranded wire, but you have to admit they’re pretty hard to screw up.

Last edited by Schroedinger; Mar 2, 2018 at 09:38 PM.
Old Mar 3, 2018 | 06:39 AM
  #28  
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Originally Posted by Schroedinger
Wire nuts are not my favorite, especially with stranded wire, but you have to admit they’re pretty hard to screw up.
I saw what you did there, and ......... I like it.
Old Mar 6, 2018 | 09:18 AM
  #29  
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short update here

cut all of my solder joints out, used stupid wire nuts, aaand now the fence works. Maybe i did have a bad connection, but I swear they were all really good. Maybe it is just Antenna black magic. who knows.

Schroed, those are some awesome trashcan finds!!
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