Electric Top Wire Grounding on Wood Fence

[Unhackable21]

I have a large Chicken & Turkey enclosure surrounded by 6' wire Fence spanning across 4x4"x6' Wood posts set at 8' apart with a 2x4" Wood Top Rail. (Picture attached) The entire top is covered and netted. Had a bobcat somehow find his way through a junction in the net (after jumping up on the net - video attached) and of course, killed chickens without eating any of them.

I have since invested in an electric top wire setup. I have a top wire set 5-6" above the wood top rail all the way around the enclosure using polywire and it is very tight. The Charger is a 2.0 joule and I have it grounded with three 6' copper ground rods spaced 10' apart. Fence tester yields 5000V and 2.0 Joules. All is working as expected

However - this is my problem. When the cat jumps up on the top rail, he is obviously no longer grounded, thus the top wire will likely not even deliver a sting.

How can I bring the ground up to the wooden top rail so that I get the effect I am after, while not having to electrify anything lower? Can I wrap polywire around the top rail, (attached to the ground post on the charger) do I run a ground wire next to the hot wire, or do I need to do something else?

Thank you in advance for any help

 

[Howard E]

Lot to unpack here. First, the 6' tall welded wire fence, even if nailed to wooden posts, can be turned into a large earth ground field (attach woven wire fence to your earth ground system) but it looks like wire fence was placed on the inside or pen side of the posts......so a cat can climb the wooden posts....and be hooked into those and never be touching the ground field when it encounters the hot wire.

So you need to find some way to install a means of earth ground to top of those wooden posts. Perhaps run a couple strands of earth ground wire on standoff insulators....or install grounded metal flashing on the posts...or even a clump of chicken wire around the top of the posts ......hooked to the earth ground.....some way to make sure cat is forced into contact with earth ground when it encounters hot wire at the top. Goal is to get an earth ground they can't step over or around....simply can't avoid it. And again, that is in addition to grounding the woven wire fence. All these grounds are not a load on your fencer. They enhance it's effectiveness.

And a second hot wire at the top would help.....this one on stand off insulators on the outside of the posts.....way up high.

And 5,000 volts is the MINIMUM. Unhook your fence from the fencer.....and test fence charger straight from hot side terminal to earth ground terminal. That is the maximum potential of your fencer. When you are done, it ought to be close to that or you have a short somewhere, bleeding off potential shock.

 

[cmom]

You may be able to put metal flashing on top of the wood railing and ground it and a hot wire or two above it so the cat would have to touch the hot wire and the grounded flashing on the top rail and up I would also put the flashing up the posts. Just a thought. Maybe also put some hot wires around the coops and pens. Good luck.
My setup isn't nearly as pretty as yours but it works. The fencing is grounded too so if anything touches the hot wires and the fencing it will get zapped but also just touching the hot wires. I do have one 8' galvanized ground rod sticking out of the ground about 6" but it works.

 

[Unhackable21]

Needs to be uploaded to youtube then linked here.

Here it is.

 

[Unhackable21]

Test it with a short piece of bare ground wire, listen for the cracking/popping sound before you proceed full scale.

I was thinking to use poly wire - the exact measurement would be 4.2" from the hot wire attached to the outside of the wood blocks. Would this work? I could even run 2 poly wires for ground - one on each side of the wood blocks - would create somewhat of a deadly triangle - 2 ground wires 4" apart near the edges of the fence top rail and a hot wire 6" standoff as shown in the pic.

I will send a picture of what this looks like.

 

[cmom]

Would these be ground wires or 2 additional hot wires?

It appears to me it would be 2 additional hot wires. You could always run a line on the outside of the 2x4 top rail and I'm pretty sure it would get hit by one of the wires. The bobcats I have dealt with were diggers. I'm surprised it jumps so high, but it is a cat. I had a regular cat touch the wire and it went straight up in the air. It definitely didn't know what happened and I haven't seen it since. Again, good luck...

 

[Unhackable21]

It will probably be back. You can run a hot wire around the bottom and bait the wire. Only turn it on when the pets aren't out. I do have a cut off switch below my fence charger. I know it jumped up on your top rail but it probably was nosing around before it decided to jump up. Here they roam at night.

I ended up doing this. I now have a wire that runs 4" off the ground, all the way around, up and over the doors. (pic) I have the system on a remote that enables/disables power to the fence now. I have to say...that 20Kv/6.7 Joule hits hard!!! Beyond the typical "test with a meter' I just had to test it myself, so I laid down a wooden pallet, put 3 rubber mats on top and stood on top of that - grabbed the wire and when it cycled, it took the air out of my lungs and it actually hurt for several minutes. I can't imagine the hit I would have felt had I been grounded! (The power supply is made for 200 miles of Bison control) I believe the cat will be deterred should it ever be brave enough to try. Thanks for the advice.

I also installed bear-proof electric doors on each coop, so I feel better that nothing will get in, even if they somehow breach the outside perimeter.

It is actually funny - the power supply snaps so loudly (and you can hear the current running through the wire on every pulse) that the coyotes that used to walk by every night, now walk around the enclosure as far as they can get from it - the cat actually came back a few times and on camera I can see that he avoided the enclosure like it was a wildfire. I have tried baiting, but so far, no animal will come near it. (which I am fine with.) We did find out that there is now a rogue mountain lion in the area that is attacking local resident donkeys, cattle and other - so I am glad I over-built.

Thanks again for all of the advice!!

 

[hayley3]

I have a large Chicken & Turkey enclosure surrounded by 6' wire Fence spanning across 4x4"x6' Wood posts set at 8' apart with a 2x4" Wood Top Rail. (Picture attached) The entire top is covered and netted. Had a bobcat somehow find his way through a junction in the net (after jumping up on the net - video attached) and of course, killed chickens without eating any of them.

I have since invested in an electric top wire setup. I have a top wire set 5-6" above the wood top rail all the way around the enclosure using polywire and it is very tight. The Charger is a 2.0 joule and I have it grounded with three 6' copper ground rods spaced 10' apart. Fence tester yields 5000V and 2.0 Joules. All is working as expected

However - this is my problem. When the cat jumps up on the top rail, he is obviously no longer grounded, thus the top wire will likely not even deliver a sting.

How can I bring the ground up to the wooden top rail so that I get the effect I am after, while not having to electrify anything lower? Can I wrap polywire around the top rail, (attached to the ground post on the charger) do I run a ground wire next to the hot wire, or do I need to do something else?

Thank you in advance for any help

Love your setup ...and wow I am shocked that the bobcat got through all that. Sorry about your chickens

 

[U_Stormcrow]

First, its a great looking set up - but yes, having the fence on the inside of the posts complicates things greatly. Otherwise, you could ground to it and run a perimeter hot top standing just off the rail with insulators, and be done.

You might actually be better off wrapping your uprights in metal, rather than capping the top. Tie the whole system to ground. Or pretend the uprights are fence posts, and attach a series of wires, alternating hot/ground/hot/ground/hot stood off from the posts, so anything seeking to climb the fence likely contacts at least two wires at some point. That a LOT of insulators though.

Neither solution is an attractive one.

I do sort of respect the cat's efforts - plenty of humans could/would not have defeated your set up. Very sorry for your losses.

 

[cmom]

I'm surprised your 2 joule fence charger doesn't put out more than 5000 volts. I had a 1.2 joule charger that averaged around 8000/10000 volts. I recently put it in my chick/grow-out coop and it's reading around 10000 volts. I replaced it with another charger on my outer coops. I like @Howard E's suggestions. I myself have metal posts. If I touch the hot wire and the fence I would get shocked. It has happened. I like the idea of running a hot wire around the top high enough so if a predator did climb up they would probably get zapped.
Many years ago a bobcat killed 14 birds one night. That was before I put the electric wires up. I forgot to shut the pop door on the coop. Big mistake and a lesson learned the hard way. I did put leg traps out. It didn't come back the next night but did the following night and I caught it and eliminated it. Recently I have been seeing a bobcat. Here is the bobcat I have been seeing outside of my chick/grow-out coop. I'm sure it knows the hot wires are there.