Searching on this site I've found lots of useful information about electric fences, but nothing geared to the complete newbie. All posts seem to assume some understanding of how an electric fence works. Since I've installed several in my day and have a degree in electrical engineering I thought it might be a good idea to remedy that situation.
First let's answer some questions you may have:
{1} "Will an electric fence harm my chickens, kids, neighbors, dog, cat, lama, camel, armadillo etc?"
No. A properly installed electric fence will cause no damage. They are completely safe.
{2} "Will my electric bill go up?"
Not enough so that you will notice.
{3} "Do they require a lot of maintenance?"
With proper planning and careful initial installation almost none.
{4} "Are they expensive?"
On a cost per foot basis they are the least expensive fence you can build for keeping out predators and pests. By themselves however, they are not effective for keeping your flock in its proper place.
Having read all of that you've decided that an electric fence will fulfill your needs. Now we'll get down to basics, the basics of electricity that is. Consider a basic electrical circuit, a battery and a light bulb. Current flows from one post of the battery through the light bulb and back to the battery. The bulb lights. Disconnect any one of the four connections or cut either of the wires, no light. Why? No complete electrical circuit. Everything from that light bulb to the computer your reading this on works on that basic principal.
Now if you've ever changed a light bulb in your car you've probably noticed that they only have one wire. "How can this be?" you ask. "OldGuy43 said that we had to have a complete circuit for the bulb to light." Simple, in a car the second wire is replaced by the metal body of the car. "Than why don't I get shocked when I touch the car?" Because electricity always looks for the path of least resistance. You aren't it. There's a lot more to it than that, but for our purposes that's enough.
With that knowledge we are now ready to discuss how an electric fence works. The first part of the circuit is the wire. It carries the current. The second half is the ground or earth. Coming into contact with the wire closes the circuit and you get shocked. Ouch!
The obvious question is, "Why just "ouch" instead of "Call 911"? The answer is twofold. First fence chargers put out a lot of voltage and not much current. It's the voltage you feel, but the current that kills you. As an example my charger is an extremely powerful one and puts out 1250 volts, but only about 1/100th of a watt. The second is duration. The charger (also know as the energizer) only puts out for a very short period of time. (Reminds me of my first wife.
) Again, using my charger as an example, one 4000th of a second per second. That's why you can let go.
Now it's time to start buying the supplies you'll need to build your electric fence. We'll start with the charger/energizer/transformer. (I've seen them called all three.)
WARNING: Do not think you can get by without one. I only mention this because I was once asked to come out to a farm to figure out why an old-timer's new electric fence kept killing his hogs. I visually (Thank God!) traced the wire back to the barn, looked around and asked, "Where's your fence charger?" His answer scared me pale, "Oh I ain't got me one a those." he said. "I jus' plug 'er inta the wall here." The whole Tennessee Valley Authority was just waiting for anything to get near that wire. ZAP!! (True story)
First you have to decide where you need it. If your run is close to an electrical outlet a 110v. unit is the most cost effective. Other options are battery powered and solar powered. Both are usually more expensive, less powerful and less reliable. Next you need to determine how long your fence will be. Remember that's the distance from the charger to the end. Chargers are rated by the length of fence they will handle, and I always like to go about 25% over on this. If you live in an area where it gets extremely dry or the soil is not a good conductor such as sand you'll want to go even longer. Do not buy one of the pet containment system chargers. Many aren't pulsed and are low powered. Not what we want to control predators and pests.
Next: Selecting the wire.
https://www.backyardchickens.com/forum/viewtopic.php?id=583754
First let's answer some questions you may have:
{1} "Will an electric fence harm my chickens, kids, neighbors, dog, cat, lama, camel, armadillo etc?"
No. A properly installed electric fence will cause no damage. They are completely safe.
{2} "Will my electric bill go up?"
Not enough so that you will notice.
{3} "Do they require a lot of maintenance?"
With proper planning and careful initial installation almost none.
{4} "Are they expensive?"
On a cost per foot basis they are the least expensive fence you can build for keeping out predators and pests. By themselves however, they are not effective for keeping your flock in its proper place.
Having read all of that you've decided that an electric fence will fulfill your needs. Now we'll get down to basics, the basics of electricity that is. Consider a basic electrical circuit, a battery and a light bulb. Current flows from one post of the battery through the light bulb and back to the battery. The bulb lights. Disconnect any one of the four connections or cut either of the wires, no light. Why? No complete electrical circuit. Everything from that light bulb to the computer your reading this on works on that basic principal.
Now if you've ever changed a light bulb in your car you've probably noticed that they only have one wire. "How can this be?" you ask. "OldGuy43 said that we had to have a complete circuit for the bulb to light." Simple, in a car the second wire is replaced by the metal body of the car. "Than why don't I get shocked when I touch the car?" Because electricity always looks for the path of least resistance. You aren't it. There's a lot more to it than that, but for our purposes that's enough.
With that knowledge we are now ready to discuss how an electric fence works. The first part of the circuit is the wire. It carries the current. The second half is the ground or earth. Coming into contact with the wire closes the circuit and you get shocked. Ouch!
The obvious question is, "Why just "ouch" instead of "Call 911"? The answer is twofold. First fence chargers put out a lot of voltage and not much current. It's the voltage you feel, but the current that kills you. As an example my charger is an extremely powerful one and puts out 1250 volts, but only about 1/100th of a watt. The second is duration. The charger (also know as the energizer) only puts out for a very short period of time. (Reminds me of my first wife.

Now it's time to start buying the supplies you'll need to build your electric fence. We'll start with the charger/energizer/transformer. (I've seen them called all three.)
WARNING: Do not think you can get by without one. I only mention this because I was once asked to come out to a farm to figure out why an old-timer's new electric fence kept killing his hogs. I visually (Thank God!) traced the wire back to the barn, looked around and asked, "Where's your fence charger?" His answer scared me pale, "Oh I ain't got me one a those." he said. "I jus' plug 'er inta the wall here." The whole Tennessee Valley Authority was just waiting for anything to get near that wire. ZAP!! (True story)
First you have to decide where you need it. If your run is close to an electrical outlet a 110v. unit is the most cost effective. Other options are battery powered and solar powered. Both are usually more expensive, less powerful and less reliable. Next you need to determine how long your fence will be. Remember that's the distance from the charger to the end. Chargers are rated by the length of fence they will handle, and I always like to go about 25% over on this. If you live in an area where it gets extremely dry or the soil is not a good conductor such as sand you'll want to go even longer. Do not buy one of the pet containment system chargers. Many aren't pulsed and are low powered. Not what we want to control predators and pests.
Next: Selecting the wire.
https://www.backyardchickens.com/forum/viewtopic.php?id=583754
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