One day on the job, Charles was apparently bonked in the head by his bricks. He had the great idea! He would build an electric fence in his own backyard. "An electric fence will keep the dogs in." Charles connected a wire to an extension cord, and managed to encircle his backyard with a 120-V strand of wire without mishap. His dogs will not be sued for puppy support with this security system in place!
The household became accustomed to the fence, and things settled down to normal, until Charles picked up a passion for gardening. Charles had a real nice set of tomatoes, and I'm not referring to his wife. One day he reached for a tomato, put his hand on the electrified wire, and there's really no need to explain what happened next.
Why did this man die? Like other inexperienced people, he thought he knew what he was doing. But his design had two major flaws. Fences constructed for dogs use one-tenth the voltage of cattle fences (which do use 120 volts.) And he needed to install a repeater, which transmits 150-microsecond pulses, to hit a cow with a jolt of juice that cuts off in time to avoid creating a pile of rare steaks by the fence.
The moral of this story is, as always, one of the guiding principles of common sense: if you don't know how to do something, don't do it!
man in Oswego County, New York, strung a 120V wire along his shoreline to discourage geese from landing on his property. A pre-teen boy touched the line and died. The homeowner was not charged with a crime, because it is apparently not against the law to protect your property in this way."
Troy Heath says, "Apparently the person who wrote the story wasn't much of an electrician either. An electric fence is not 'one-tenth of 120 volts' -- if it were, you could shock yourself touching the terminals of a car battery. An electric fence is in fact normally a few thousand volts. Low amperage is the reason why animals and people aren't killed when they touch it. The following is an excerpt from an electric fence manufacturer's FAQs: 'It's similar to getting a static shock from a TV screen: the voltage can be as high as 50,000 volts -- 5 times higher than an electric fence charger. With no continuous amperage, there can be no damage. That's what UL and CSA certify!' I was electronic engineer before changing my career to networking. I am certified by the ISCET (International Society of Certified Electronic Technicians."
Gunpowder says, "I am astounded by the stupidity of the above comments. Electric fences do have high voltages on par with 50,000 volts. However, correctly manufactured electric fences have current limiting devices that keep the fence from killing creatures so unlucky as to touch them. Pulses of energy cannot be used because they are too close to AC (alternating current.) Alternating current makes muscles contract at a very fast rate, making it difficult to free oneself from the fence. This action can also cause a heart to fibrillate, potentially causing death. It only takes one quarter of an ampere to kill a human being. Anyone who cares to make an electric fence had better make note of this since it is illegal to use electric fences that can kill, 1/4 amp or more, to protect property. I suggest that Troy learn more about electricity. Car batteries wont give you a shock?! Tthis guy will win an award soon! I am a product safety engineer and know what I'm talkin' about!"