One morning when my husband and I went out to feed and milk our Nubian goats, we were horrified to discover the bucks paying an unscheduled visit to the does. By the time chores were done and all the goats were back in their right places, and we got around to examining our electric fence to see what had gone wrong, the temperature was already in the mid 90s and the humidity was brutal. Even though we have cut–out switches to disconnect sections of the fence, trotting up and down the fenceline to flip the switches left us exhausted. What we really need, I thought, is a remote control for the fence energizer, like one that turns the TV on and off. This would simplify DIY electric fence maintenance.
Well, guess what! Someone was way ahead of me with that thought. Shortly after this incident occurred, we received a notice from Kencove Farm Fence Supplies about their new remote fence controller. Well, let me tell you, we beat a path to their door to get one.
Or rather, two. We have two goat barns, each with its own system of fencing and cross fencing on separate energizers. Not knowing at the time how the remote works, we wondered if one remote might get confused (and confuse us) by turning both energizers on or off at the same time. But it turns out the remote manages only whatever energizer is attached to the fence you need to work on. Nifty, huh?
Selecting the Right Energizer
Energizer, fence charger, fencer, fence controller, power unit—all these terms refer to that little box responsible for the big jolt you get if you touch an electric fence. It works by converting household electricity or battery generated power into higher voltage, then sending the current through fence wires in steady, short bursts. You can hear the energizer’s slow click–click–click as it sends out the pulses.
Switching our system to remote control meant we needed compatible remote–ready energizers, which we deemed worth the expense if it would save us hours of frustration and exhaustion when tackling DIY electric fence maintenance. The first step was to make sure we got the right–size energizers for the job. An energizer that’s of the correct size for a particular fence creates an effective sphere of intimidation around each pulsed wire, discourages weed growth, and overcomes minor flaws in the fence’s construction. Trying to save money by getting an energizer that’s too small can render an entire fence useless.
To determine the right energizer size we had to know how much fence wire needed to be energized. For that we paced off each fence line and multiplied the fence length by the number of electrically charged (hot) wires to determine how many miles of fence wire are involved.
“Miles of fence” is one way to measure an energizer’s output. The term doesn’t refer to the length of the fence itself but to the total length of all the individual hot wires. As an industry term, “miles of fence” is measured in a single continuous strand, three feet off the ground and free of weeds. In other words, it’s determined under ideal laboratory conditions. In actual field conditions, the distance a pulse can travel along a wire is considerably less due to climate, weed load, fence construction, wire gauge, and the electromagnetic resistance arising when two or more wires are strung parallel to each other. Still, it’s a starting place for determining the appropriate size for an energizer.
Energizer output is also rated in volts and joules. Volts measure electrical pressure, or the amount of force behind each pulse. The higher the voltage, the greater the chance that a pulse will penetrate an animal’s coat. Joules furnish the energy that pushes the voltage along the wires; most energizers are rated according to their joule output.
Going back to “miles of fence,” according to guidelines on the Kencove website, an effective energizer needs at least one joule for each six miles of energized wire. Their remote–ready energizers are rated in 3, 6, 9, 13, and 24 joules. According to the guideline, then, the 9–joule energizer can handle up to 54 miles of hot wire—the right size for our goat facilities.
The Grounding System
Along with installing new energizers, we decided to re–evaluate our grounding system. Under normal circumstances, a fence’s hot wires are insulated from the earth and the circuit is open. To generate a shock, current must flow from the energizer through the hot wires and back to the energizer through the soil. A person or animal standing on the ground and coming into contact with a hot wire closes the circuit and feels the consequences.
To get a complete circuit, the energizer must have good contact with moist soil. Contact is provided by means of a galvanized steel 1/2–inch or 5/8–inch diameter ground rod driven into the soil and connected by galvanized fence wire to the energizer’s ground terminal.
Since moist soil is more conductive than dry soil, a ground rod must be driven deep enough to make good contact with always–damp earth. In our dry area of Tennessee, that means at least six feet deep. Further, to ensure good contact with moist soil, at least three ground rods are needed per energizer.
The first rod is driven into the soil as close as possible to the energizer, but outside the barn to minimize the chance of starting a fire or electrocuting livestock in the event lightning should strike. The rod is pounded into the soil with a post driver until four to six inches of rod remain above ground. Because our area is dry for at least half the year, we help improve soil moisture by forming a depression around each rod to better hold runoff, as well as water dumped there while cleaning livestock water buckets.
The two additional rods are spaced 10 feet apart, and the three rods are connected in series with ground wire and ground rod clamps. Since the rods stick out of the soil and have wires running between them, we put them on the side opposite livestock to prevent injury, and keep them close to the fence line to prevent mower damage.
Ground Return versus Wire Return
When a fence’s circuit is completed by current flowing through the feet of an animal standing on the ground, the system is called a ground–return or earth–return system. This type of system works fine for a relatively short fence in an area of even rainfall, where the soil is conductive and predators such as the wily coyote are not a problem.
Under certain circumstances, though, the earth–return system doesn’t work well. Extremely dry soil like ours, for example, is not very conductive. In winter, the earth may be insulated with a layer of packed snow. Sandy, rocky, or frozen soils are self–insulating.
The problem is compounded where hoofed animals are involved, especially small ones. Hooves have more insulation value than soft pads. Animals with tiny hooves, like lambs and kids, are not only insulated from the ground by their hooves, but don’t have much soil contact to start with. In addition, young stock and some predators get through a fence by leaping between the wires. They don’t get a shock because their feet are off the ground.
In such situations, an earth–return system isn’t nearly as effective as a wire–return system. A wire–return system is less dependent on soil conditions. It deters animals having built–in insulation and those performing tricky maneuvers like jumping through a fence instead of crawling under it or trying to climb over it. Unlike the earth–return system, it works well even for long fences.
The usual wire–return system involves connecting every other wire to the soil by means of ground rods. An animal that touches both a hot wire and a grounded wire completes the circuit and feels a jolt. Even if the animal hits the fence with all fours off the ground, it just has to touch two wires to close the circuit.
Exactly which wires should be grounded is debated among electric fence owners. Some ground the bottom wire to reduce energy loss due to encroaching weeds. Others ground the second wire up as a better way to deter young stock and small dogs. With the bottom wire hot, an animal pushing under the fence has two ways to complete the circuit—by touching the earth and the bottom wire or by touching the two lowest wires.
Our six–wire goat fence, working from the bottom up, is hot–hot–ground–hot–ground–hot. In deciding exactly which wires to energize and which to ground, the following guidelines must be kept in mind:
- Energize the wire nearest the nose height of the animals to be controlled.
- Keep the hot and ground systems separate from each other.
- String hot wires and grounded wires at least four inches apart so they won’t spark or inadvertently touch.
For a wire–return fence that’s more than 1,000 feet long, extra grounding rods are needed, each connected to all the fence’s ground wires. For a long fence where the soil is reasonably moist, the rods may be spaced every 3,000 to 5,000 feet. For a short fence and/or where soil conditions are dry, rods should be spaced every 1,000 to 1,500 feet. Evenly spacing the rods isn’t as important as putting them in low spots where the soil stays moist (where the grass is greenest).
Shorts and Leaks
Just as important as establishing an adequate grounding system is making sure the hot wires have no contact with the ground. A direct connection would, of course, result in a dead short. Lesser contacts, called shorts or leaks, drain energy from the fence, making a plug–in system less effective and drawing down a battery–operated system more rapidly.
Energy leaks have any number of causes: grass or weeds growing against hot wires or windblown twigs or branches lying across them; cracked insulators; bugs, leaves, or dust lodged in insulators; salty sea air; a broken wire. Most of these situations cause arcing—pulses of current that, instead of flowing smoothly from one place to another—jump across a narrow gap by means of a spark.
When arcing occurs, you can usually hear the snap of the jumping spark, which can help you find and correct the source of leakage. Whenever you check your electric fence, listen for problems as well as look for them. If the source of snapping sounds eludes you, go back at night and you’ll actually see sparks fly.
As an additional indicator that something is amiss, we use strategically placed battery–operated fence alert monitors that flash when they detect low or intermittent voltage on the fence. It’s hard to ignore a bright red flashing light that’s so clearly visible at night from as much as 100 yards away.
Shorts are also detected by the new energizer’s unique built–in diagnostic indicator. A ground condition indicator light warns when the ground terminals exceed 1,000 volts—time to water the ground rods. A voltage indicator light warns when the voltage drops below 3,500 volts—time to look for (and fix!) whatever is causing the short.
When a fence demands attention, a hand–held fence tester is indispensable for finding the problem. The fence testers we’ve used in the past had two terminals, one on the unit itself and another connected to the unit by a length of wire. The first terminal is attached to a hot wire, the other to some part of the ground system. With both terminals in place, the unit indicates how much voltage is getting through.
I can’t recall how many fence testers we’ve gone through. Some had delicate terminals that broke easily and needed constant repair. Others got tossed in the trash because they had such a poor display you couldn’t read it on a sunny day. Using any of them involved walking down the fenceline looking for problems, then walking back to the energizer or nearest cut–out to turn off the juice, walking back to fix the problem, walking back to turn on the fence, walking back to check the repair, and on and on.
Sometimes, especially after a big storm blew debris all over our fences, we’d use two–way radios with one of us waiting at the cut–out while the other tackled any DIY electric fence maintenance necessary. There was always the chance of a misunderstanding as to whether the fence was hot or not, until the fence walker found out the hard way. That’s really not good for a marriage.
Kencove’s combination remote control and fence tester that comes with the remote–ready energizer is sturdier and easier to read than any I’ve seen so far. The top of the remote has a metal hook that, when pressed against a hot wire, reads information about the voltage, amount of current flow, and direction of current flow on a nice big display. My minor complaint is that the fence hook is a tad short, causing it to slide off the wire unless you’re careful to hold it steady. And I believe the remote should be kept in a pouch to prevent the display from getting scratched when the unit is tossed in a glove compartment or tool box. Luckily we happen to have an unused amp meter pouch with a belt loop that perfectly fits the remote.
Now we come to the truly exciting part of our new system: using the remote control to turn off the juice without walking anywhere or relying on a partner for DIY electric fence maintenance. And it works on any kind of electric fence—metal, poly wire, ribbon, braid, or net. When you find a problem and want to turn off the current to fix it, you hook the controller over a hot wire and press the “off” button; you know the fence is off because the display tells you so. After completing your DIY electric fence maintenance, you hook the controller over any hot wire and press the “on” button; you know the fence is on because the display reads the voltage and current. It’s that simple!
The easy–to–read display on this fence tester says the hot wire voltage is 7,200 volts, plenty enough to deter most animals. When the display says “OFF,” you can safely make your fence repair without having to walk back to the energizer or nearest cut–out switch.
Since installing the new system, completing our DIY electric fence maintenance has become much easier. And we haven’t had a single unscheduled goat visit, even when a doe in heat persisted in teasing the bucks directly on the other side of the fence.
But I have to make a tiny confession, if you promise not to laugh. After decades of walking back and forth troubleshooting fences and completing DIY electric fence maintenance, I’m almost embarrassed to mention how many times we walked to the energizer to turn it off while carrying the remote control. But it has finally sunk in: No longer do we have to walk our legs off while performing DIY electric fence maintenance!
Gail Damerow is the author of Fences for Pasture & Garden, available from the Countryside Bookstore. For more tutorials on fencing, visit these great stories from Countryside Network: 5 Homesteading Fencing Mistakes and Why Choose Electric Fencing for Horses, Cattle and Other Livestock.
Originally published in Countryside May / June 2013 and regularly vetted for accuracy.