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Electric Fence Charger

  1. Jan 8, 2008 #1
    I recently had trouble with cats getting into the back of my pickup and tearing into the trash bags I have before I can dispose of them.

    I decided to hook up my spare electric fence charger, which puts out a pulse about every second.

    The bed of my truck has a plastic liner, so it's insulated. I have the charger grounded. I cut and laid in a section of galvanized fencing on the bed, and attached that to the charger.

    My question is, if a cat gets in there again, will they get a zap, or will it not work since they aren't then grounded.

    I used a fence tester, which has a small neon tube that lights up. I just connected it to the fence without grounding the tester, and it did light up slightly. So I'm thinking the cat may not need to be grounded.

    If anything, I don't think the cat would get the full charge because of not being grounded, which is fine. I just need enough to discourage it.
     
    Last edited: Jan 8, 2008
  2. jcsd
  3. Jan 8, 2008 #2

    FredGarvin

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    I'm thinking you're correct in that it won't get much because it is not grounded. Think of a bird sitting on a wire.
     
  4. Jan 8, 2008 #3

    Danger

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    You can eliminate the doubt by grounding the base plate. :devil:
     
  5. Jan 8, 2008 #4
    There isn't a base plate. It's a 3' x 2' section of galvanized fencing which has the charge. I can't put grounding in the truck or I'd have a short. Unless I can somehow separate the charges, but still have enough coverage.

    Anyway, the fence tester did light up without being grounded, so maybe there's just enough potential between the metal of the truck and the charged fencing material to work.
     
    Last edited: Jan 8, 2008
  6. Jan 8, 2008 #5

    Danger

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    I misunderstood the set-up. I was thinking of just running a strand of 2 or 3# welding cable from the chain-link to the ground. I had assumed that it was your ground plate, with another electrode as the 'hot' side. Sorry.
     
  7. Jan 8, 2008 #6
    You don't have to apologize.

    I've set this up already, and I'll check in the morning if it kept them out.

     
  8. Jan 9, 2008 #7

    FredGarvin

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    If they're anything like my cats, it will take a much higher level of security to convince them to stay away. Persistent little buggers.
     
  9. Jan 9, 2008 #8
    Before you go too far with this, think about the gas tank and whether you're about to make little sparks in there.
     
  10. Jan 9, 2008 #9

    stewartcs

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    Why don't you just leave the trash out of the back of the truck until you're ready to transport it, or put it in a container with a lid?
     
  11. Jan 9, 2008 #10

    stewartcs

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    What is the charger grounded to...the earth? If so, in order for the cat to complete the path of the circuit and get a jolt, it would have to be touching the earth.

    CS
     
  12. Jan 9, 2008 #11
    I realized it didn't work this morning since the trash was torn into, but not all that much. The fencing I used was deer fencing, which is galvanzed with about 1.5" x 4" rectangles, so it may have been too thin. The charger was clicking the whole night, so it wasn't shorted.

    I'd probably need to do alternating rows of shock, ground, shock, ground in order to work with this.

    I don't have it close enough to any metal to create arcing. The bed liner is fairly thick, so it insulates well. Also, the truck is on it's tires, so it's not usually grounded. I am using a separate wire for that. But if I redesign this, I can keep it all in the truck.

    I also do have a can with a lid, but I end up having too much to fit in there.

     
    Last edited: Jan 9, 2008
  13. Jan 9, 2008 #12

    rbj

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    but the bird flies to the wire and the cat will possibly climb to the wire. if have two or three or four parallel wires to your electric fence where you alternate hot/ground/hot/ground, i think a cat will have difficulty climbing on one without touching the adjacent wire.

    BTW, electric fence contollers are meant to stop cattle and are supposedly safe enough to not kill the farmer's 6-year-old kid if he/she is playing out by the pasture. i've gotten zapped pretty good a few times when i was a kid. but, when i was a teenaged kid working for a dairy farmer, we would come upon steel posts of the fence (with a good but small insulator separating the hot wire from the steel post that was clearly grounded) where there was a carcass of a bird that evidently flew and landed on the fence, then hopped over to the post and pecked at the grounded post while standing on the wire. cats are bigger than sparrows or swallows but i am not sure that a cat would survive a good electric shock from the electric fence controller. i dunno, i don't remember what the current limitation is that is built into the controller (but the docs that come with it should say).
     
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