Electric Fence = Multimeter Death?

I use the shovel method but an even better way is to use a little kid. Years ago I had a good electric fence up to keep the dogs in the yard. One of the weed killer types. I was out working in the yard and my daughter was out playing. I told her to stay away from the wire and not touch it. You people with kids knows how that went. She defied me and kept touching the wire. She finally touched it when a pulse went off and she screamed. Her mother came over and told her that Daddy said not to touch it. She stared at me so I told her her to go ahead and touch it again. By damned she did. After the next time she got shocked she never went within 5 feet of the fence. At least I didn't have to worry about her getting lost.
 
As a kid my neighbor kids and I were always running around in the woods etc at night. Especially in the summertime! One night, without realizing how close to the fence line I was……. I pee’d on the electric fence…..
 
I did this to a meter trying to measure the output of a microwave oven transformer. It smoked the meter and damn near killed me (the current went right thru the meter). If I hadn't been sitting on a wooden bar stool, I would be pushing up daisies.
It's not the volts that kills you, it's the amps. Anything over 100ma is potentially lethal. A microwave oven is particularly dangerous in that it is capable of generating as much as a kw of power which can amount to currents of around an amp. For those working with high voltage, the safety rule is to keep your left hand in your pocket as a current passing through your left hand passes through the heart and is more likely to be fatal.

I have had more than my share of brushes with high voltage in my 78 years. The highest voltage that I had the misfortune to experience was around 50,000 volts. It came from a Leyden jar charged from a van de Graff generator. A Leyden jar is a primitive type of capacitor made by gluing foil the the inside and outside of a jar. The capacitance is very low which was a good thing for me. It was after a high school science class and as I was talking to the teacher, I absent mindedly picked up the Leyden jar and touched the ball to my lip. To add insult to injury, as I was explaining what had just happened, I touched the ball again with my finger. That is how I discovered residual charge.

The closest that I have come to leaving this mortal coil was when I was working on a ham radio transmitter and accidentally touched the 400 volt d.c. supply. What saved my life was that my muscle contraction pulled the transmitter off the bench and to the floor, breaking the circuit.

Beyond that, I have had numerous experiences with mains voltages which remind me that it is not a good thing to do. They are usually simple brushes with the voltage source so contact time is too short to do any serious damage but the pain is intense enough to be more careful. As I tell my wife, pain is nature's way of telling you that you screwed up.

I don't fear voltage but I do respect it.
 
As a kid my neighbor kids and I were always running around in the woods etc at night. Especially in the summertime! One night, without realizing how close to the fence line I was……. I pee’d on the electric fence…..
That was always a dare with the farm kids. Something like a rite of passage.

When we had livestock, we used electric fences. They would constantly short out from weed growth so testing was common and often. I made a tester from a short length of insulated wire terminated with an litigator clip, an insulated handle, an a bare probe tip. Clip the alligator clip to a metal tee post and bring the probe tip near the fence wire. If a spark jumped, you were good. I used the same tester to test for ignition voltage on the tractors, outboards, and small engines..
 
I can remember as a kid playing with electric fences. The type used to keep in cattle around large cut corn fields in the fall, that would burn weeds and grass off the wire. Touching the wire wall standing on a chair. Or using a stick. Trying to get my mind around how electricity worked. And why it messed with the AM radio. Guess that lead to a career ...
 
Voltages around 1500 to 2000 are especially lethal, that's why microwave ovens are so dangerous to mess with inside.
Electric chairs also.. :cupcake:
 
Years ago I had a "pet" goat, mainly to keep the poison oak and thistles under control in my side yard. Used an electric fence to keep him contained. I used old 48" fluorescent tubes as "indicators" at the corner of the yard. The trick is to solder up about 5-10 10K resistors in series and put them between the fence wire and one end of the tube. Ground the other end of the tube. If desired, you can slip a length of vinyl tubing over the resistor string. The resistors prevent the fluorescent tube from loading down(shorting) the fence wire. With the tubes at the corners of the yard, I could see the somewhat faint flashes at night, and be sure the fence charger was doing its thing. See the post by markba633cs (above) for a similar suggestion.
 
How electricity effects the human body is an interesting sidebar. I did a lot of studying (reading, not live experiments) on it at one time out of curiousity. Nerves use an electro-chemical process at the junction (synapse). So electricity impacts your nervous system. Touching a fence will often cause your arm to involuntarily twitch/contract. I learned to touch fences with the back of my hand, not to grab them, as the stronger muscle contractions to close your hand can keep your hand locked around the wire. That current, running through the wrong place such as the heart, will mess up the somewhat delicate process that controls heart contracts. This is one case where knowing CPR is helpful, as people who are thus effected have a chance of being revived by CPR (after the power is gone). Current through the brain is obviously a real mess, but it is not a common path for someone to get electrocuted. Current doesn't flow through the body uniformly, so what gets effected is not easily predicatable, although it does generally go from entry to exit point. It isn't just a simple matter of current that kills, that path is key. And that gets impacted by all sorts of things, frequency in AC being one in particular. This makes electrocution somewhat unpredicatable. Of course, on high power sources, such as lightning, the electricity will burn a path through the body. I always wanted to see an autopsy on one of those, I got to see some interesting autopsies, but never on a high voltage electrocution. My father (a pathologist, long retired now) said they actually will trace the electrical path through the body on those to see what organs were damaged.
 
I too had an early experience with an electric fence (Although I didn't understand the actual voltage involved, until today).
Many, many years ago, I had a job on a state survey crew, as one of the two "rodmen" on the 4 man crew.

We were laying out side stakes for a new road, though some old farm fields, using a 100' steel tape - It was a wet, dewy morning, in tall grass.
The other rodman, old Ernie, who was on "head chain", took the tape through some bushes, and called back, asking if I was holding over the last stake with my plumb bob - I replied yes, and he then promptly dropped his end on an electric fence!
He was cackling about it for a half hour - I did get him back later for it, but that's another story .....
 
So, kids will forgive you but wife, not so much.

Back around 1990 my girl-friend touched a dog-type (weak) electric fence wire and didn't get a shock. The ground was dry and she had on rubber-soled sandals. She asked why no shock and I said that it was because she wasn't grounded and that if she had her toe touching the ground she would get shocked if she touched it "try it if you want to". So, she did it (with the expected results). She was ******, to say the least. She married me anyway. However, I've never been forgiven for "telling her to do it". I hear about it from time to time.
 
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