testing electric fence?

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My mom has a vegetable garden surrounded by railroad ties. It is fenced to keep the deer out. To keep the chipmunks, woodchucks and rabbits from trying to get through the fence, my father ran electric fence wires along the tops of the ties.
It does not appear to work. The animals are running along and crossing over the wires. The charger puts out 20,000 volts a/c. My meter doesn't go up that high. Searching finds there are $125 fence testers.
When the wires are attached to the charger, the fence okay light on the front does not flash. But the unit does click every second. When the wires are removed, it clicks and the light flashes. For circuit resistance my meter showed no short.
Does anyone know about these things? My mom is using a farm product in a suburban backyard and there aren't many around to ask.
Don. www.floorborders.com (e-mail link at home page bottom).
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On 7/5/2016 9:51 PM, Don Wiss wrote:

Electricity works in a complete circuit. Does the fence charger have a way to connect to earth ground?
On the top of the railroad ties, please try running a second wire, this second wire connects to earth ground. The second wire should be close enough that a critter can easily touch both the fence charger wire, and the ground wire.
OTOH, maybe the rail road ties may be grounding the fence charger. They do sell plastic insulators, which may be needed.
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It worked for years. There was even a charger before this one. But my father was alive then.
There are two electric fence wires running across the top. There is a grounding rod. There are insulators. There is lots of wire.
Don. www.donwiss.com (e-mail link at home page bottom).
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On 7/5/2016 10:21 PM, Don Wiss wrote:

Check with the local humane society. You may have the new non conductive rodents. Just like glyophosphate, and roundup resistant crops, there might be charger resistant rodents.
Well, not all seriously.
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On 7/5/2016 9:21 PM, Don Wiss wrote:

Buy her some Rat-Zapper's from Victor Pest
http://tinyurl.com/hl9djx4
They are battery operated (AA's) and work like a champ for mice and gophers. We had them to control field mice in the garage but this year we've had a slew of chipmunks all of a sudden. Set them out near the garden and flowers where the little bastards were digging and feasting.
Dumbbells walk right into the trap even with any bait (we use a couple of pieces of dry dog food for mice) and they get zapped. One trap netted four chipmunks in one day. Not much of a problem any longer. If you put them in the garden you need to protect the trap from rain but Victor makes an enclosure for that purpose. You could also make one out of something like a large Tupperware container.
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We are not currently trapping. When my father was alive he trapped. One summer he got 32 chipmunks. If my mother successfully caught a woodchuck, she would not be able to lift the trap. When we tried is was hard to successfully trap just before I visited. (Mainly as no woodchuck would go in the trap. Instead squirrels would trip it.)
I'd like to fumigate the woodchuck burrow. You have to seal up all but one entrance. Problem is one entrance is now under the neighbor's tool shed.
Don. www.donwiss.com (e-mail link at home page bottom).
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On 7/5/2016 10:21 PM, Don Wiss wrote:

I'm thinking there is enough leakage through the logs to make the controller think it's a short circuit. Your meter only uses low voltage to measure the resistance. Maybe the old fence controller had more output and was able to overcome the resistance to ground. I'd use the yellow plastic insulators to keep the wires from touching the wood.
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The current controller worked for years before this summer. The prior one worked for many years before this one.

It is a large and complicated setup done by my dad years ago. No one is going to rewire it now.
Don. www.donwiss.com (e-mail link at home page bottom).
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On 7/6/2016 8:57 AM, Don Wiss wrote:

Sounds like something along the line(s) changed. If there are branches in the circuit, maybe you could troubleshoot by opening some of the branches to find out which if one is shorting out the line.
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On 7/5/2016 6:51 PM, Don Wiss wrote:

If it's AC, you can try wrapping a (insulated!) wire around one of the fence wires and feed that to a high-impedance volt meter. Or, start by using it to "power" a neon bulb (to eliminate any risk to the VOM). You'd do this with power *off*, of course. :>
Here, you're just looking to see if it is developing *any* sort of (high) potential.

At 20KV, you're not looking for a short in the "zero ohms" sense. The fence "charger" is expecting to see a VERY high resistance (megohms) when not in contact with critter flesh. It is probably only capable of putting out a few milliamps, maximum (1mA @ 20KV = 20W!!). You can make a guess based on the rating of the *primary* side of the "charger" (e.g., what does it draw from the 120VAC mains?)
Said another way, a 1mA load would look like 20 Mohms (20,000V/0.001A). If you are seeing *any* resistance on your DVM, then the fence charger thinks the fence is "shorted".
(Hint: grab the two leads of your DVM in your fingers with the selector set on highest "ohm" range. THAT is what the fence is expecting to encounter when you -- as an oversized "critter" -- touches the fence!)
I suspect the click you hear is the charger shutting down and restarting, cyclicly.

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On 07/05/2016 08:39 PM, Don Y wrote:

Any charger I've run into clicks every time it pulses. If it's not clicking it's dead. The redneck method of testing the fence is to pick a blade of whatever you've got growing and lightly touch the fence. The dumb redneck method is to piss on the fence.
If the smaller animals are on top of the ties when they touch the wire they may not be grounded. Or they might just be hungry. Mix an elk, a field full of alfalfa and an electric fence and you'll find out how many feet of wire, insulators, and posts a determined elk can drag.
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On 7/5/2016 11:11 PM, rbowman wrote:

The smart ass redneck way is you get a city cousin to piss on the wire.
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I thought about a neon bulb tester. I'm sure if I hunted I could have found one in my father's workshop. I can take mine out next visit.

When I wrote the original post I realized I should have brought back with me the instructions sheet. Without it I don't know much about the charger. I do know it is an Agway ALI30C. But I can find little about it on the web.

I did not see any resistance in the DVM. What I'd like to have is: http://www.zarebasystems.com/store/electric-fence-accessories/fd1
But considering that my mom is 94 and it isn't that important, it is a bit of a stretch.

I tried it and I couldn't get any reading.
Don. www.donwiss.com (e-mail link at home page bottom).
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On 7/6/2016 3:45 AM, Don Wiss wrote:

Or steal one out of an illuminated wall switch.
OTOH, it *appears* (from your description) that the fence charger indicates "power available" via the light. So, you can probably use that and jigger around with the fence wire to see when you've cleared the "short" (keeping in mind that a wet branch leaning on the wire is a short!)

Assume power in = power out, for starters. So, if you can get a voltage (or current) rating on the output side, you can guesstimate the current (or voltage). I think you'll find damn near anything will look like a "short" at the voltages involved.

Compare what the fence reported to what your hands holding the test leads reports.

Same as the fence, eh? :>
For a definitive answer, you need a higher impedance VOM. But, chances are, the problem *is* a "short" -- you'll just have to decide if it is the wooden fence post to which the wires are attached... or, the insulation on one of the wires feeding the fence... or...
But, you *know* the charger behaves differently with *no* load connected! ASSUME it is working in that configuration. See what you can do to make it stay working while you have fence wire attached.
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On Wed, 06 Jul 2016 06:16:29 -0700, Don Y

So is a blade of grass. A "weed chopper" will latch on and burn off the grass or branch (and has started MANY grass fires) - bu the puny little Agway won't stand much of a chance.
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wrote:

Jast grab on. If you can hold it - it's not working. It won't kill you - it'll just "recharge your batteries" (unless you have a pacemaker).
I've dealt with electric fences for years as a "farm boy".
The "agway" is likely a store brand - rebranded from some other manufacturer - and likely old enough not to have any reference on-line.
I wouldn't recommend grabbing on to a "bull - dozer" or "weed chopper" - but just about anything else is just VERY uncomfortable - not dangerous. The Dozer or Chopper will put you on your knees.
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Wed, 06 Jul 2016 02:39:30 GMT in alt.home.repair, wrote:

It could be.. It could also be a relay that completes the circuit to the coil briefly. Some use solid state relays, some don't actually use a relay but an IC performing the same task, instead. Others, use a mechanical relay and/or the same type of flashing relay on a car; hence the clicking sound.
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On Tuesday, July 5, 2016 at 9:51:47 PM UTC-4, Don Wiss wrote:

if the railroad ties are treated with creosote or other noxious chemicals you are eating them. the chemicals migrate from the wood and get into the dirt you vegies are planted in.
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First, there aren't many vegetables in the garden. It has become too shady. Most vegetables are grown in a community gardne. And since deer love hostas, those plants now live in there.
I looked up creosote. I found "Creosote that seeps into the soil may damage roots directly, but plants will not absorb the substance into their root tissue." From:
http://homeguides.sfgate.com/creosote-harmful-garden-77104.html
Don. www.donwiss.com (e-mail link at home page bottom).
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On 7/5/16 8:51 PM, Don Wiss wrote:

There's a diagram here <http://www.agrisellex.co.uk/information/how-a-fence-works.html showing how one works with farm animals. The animal completes the circuit when it touches the wire. I wonder if using something like screen door screen on top of the ties could act as the earth. Connect the screen to the ground of the fencer. Then run the hot wire slightly above that. You'll have to keep the hot wire from contacting the screen. The animal needs to make the connection between the two. Normal insulators probably wouldn't be practical. Maybe buy some pvc pipe and lay it on the ties. A single 10' piece of pipe would make quite a few wire stands. The wire will have to be tight to keep it off of the screen even with many supports. One can buy fence stretchers. Maybe some springs at the end(s) to keep tension? Testers at Amazon: http://preview.alturl.com/ymkf6 Price range is $10 or a bit more. One can also buy polywire, polytape, and polyrope. Maybe the visual part would help after the animals get a shock or two.
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