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Electric conductivity loss due to weather on electric fence wire?

  1. Aug 4, 2017 #1
    Greetings Denizens!,

    I'm building a small "zapper" for the purpose of keeping critters away from a deer feeder. Other than volts and amps ratings, I believe it is, for all intents and purposes an electric fence, just in a unique configuration (shape, not electrical specs - those are within the "normal" output specs found for DC fence chargers - similar to that of a dog's shock collar at around 2kv.)

    It will live outside, year round, year in, and year out. I never want to take it out of the field. To that end, I was considering the possibility that corrosion to the galvanized fence wire might reduce, or eliminate the effectiveness of the device.

    Does anyone have any personal knowledge, or know of a resource that can give me some novice-level information on just what I can expect?

    I could use stainless steel wire, but that does not come cheap. I also expect it will not be as malleable, and therefore will be harder to work with, in the small spaces I will be fishing the wire through, and wrapping it around.

    Another consideration - does Petroleum Jelly readily conduct electricity? I also have a chromed cage that will be the ground lead for the device. Eventually, I know it will rust. If I smear Petroleum Jelly on it, will it still be an effective ground?

    Thanks in advance for any help offered.
    Last edited by a moderator: Aug 4, 2017
  2. jcsd
  3. Aug 4, 2017 #2


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  4. Aug 5, 2017 #3
    Interesting alternative.

    I already have the galvanized wire, however, and was trying to figure out what to expect, long-term, as far as corrosion from rain, snow, and sun.

    I think I may just go for it, and if it eventually fails to preform as needed, I know where I'll go, next.

  5. Aug 5, 2017 #4
    If you are using DC, i think there exists two possible polarity assignations:
    1) the wire is positive wrt ground. This will accelerate oxidation.
    2) wire is negative wrt ground. This can inhibit oxidation of the wire.
  6. Aug 5, 2017 #5
    If I assemble it correctly (after I finish designing it, that is,) the wire in question will definitely be the positive lead....or will it?

    At the moment, I am intending to have the outer cage, (which is chrome plated steel,) be the ground side of the circuit.

    What if I swapped the wires, and had the cage be the hot side, and the wire be the ground? Since this system is isolated from all other power sources, and will not be attached to the earth for ground, does it really matter which is which, as far as the circuit is concerned? If having the galvanized side negative makes it last longer, that sounds like a good thing, because the cage, though expensive by comparison, is replaced in a matter of minutes with a socket wrench, whereas the wire is likely going to take hours of painstaking threading through small holes to form the surface the critters will touch.

    Then again, the "shocker" side of the circuit, is AC, I think, even though the power source is DC, in which case that all means nothing, I suppose?
  7. Aug 5, 2017 #6
    I was centered on the shocker side. Even being AC, the voltage on the wire could be clamped to have a mean negative potential wrt the ground. It can be done using a condenser, some resistors and a diode. There are practical difficulties mainly for being High voltage and for being pulsating, but I think it can be done. The generator box can be grounded too and I recomend you to do. The kind of power source is not relevant.
  8. Aug 5, 2017 #7
    Thanks, I'll try to take that into consideration, as this moves forward.
  9. Aug 6, 2017 #8


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  10. Aug 6, 2017 #9
    Thank you - 20 years should be enough for my purposes.
    My charger needed to be about the size of a deck of cards, so it could fit internal to the equipment.
    Item found, after weeks of looking, and trying to design and build one.
    cost was 15 bucks.
    I can't post pictures here, or I would show the completed project, which I hacked away at on the kitchen table, until it was (nearly) complete. All I need is a decent switch so it can be deactivated for servicing, bu the local stores have lousy options, as does eBay. I have a couple other options, before I resort to online ordering, and shipping costs that exceed the price of the switch...
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