November 22, 2013

Electric fencing basics that you should know.

Fencing

Fencing is usually the largest capital expenditure on a sheep farm. In many cases, existing fence can be modified for sheep-raising. Two types of fencing are required on sheep farms: perimeter and interior fencing. 

Perimeter fencing is usually installed around the boundary of the property (or grazing area) and is the first line of defense against predators. It is intended to last for a long period of time and should be constructed of high quality materials. Suitable perimeter fences for sheep are multi-strand, high-tensile, electric fences and woven wire fences with electric offset wires and barbed wires at the top and bottom of the fence.

Interior fences (or cross fences) are used to subdivide fields into smaller areas (paddocks) for grazing. Interior fences may be constructed from permanent, semi-permanent, or temporary fencing materials. 

While an interior fence does not need to deter predators, it does need to be good enough to keep weaned lambs away from their dams and/or rams away from ewes. Temporary fencing can be used to enclosed areas for temporary grazing (e.g. a corn or wheat field). 



Perimeter Fencing

High-tensile, electric

High-tensile electric fences last for a long time, are relatively easy to construct, and cost less than other types of fencing. Whereas cattle can often be controlled with 1 or 2 strands of electric wire, sheep require multiple strands, not so much to keep them in, but to keep potential predators out. 

Five, six or seven strands of 12 ½ gauge high-tensile wire is common for sheep fences. The bottom wires of the fence are more closely spaced than the top wires. Wire spacings of approximately 6, 5, 5, 8 and 10 inches are typical. In areas where there is relatively even rainfall and some green vegetation most of the year, it is recommended that all wires be hot. 

Ground return wires are recommended where there is low rainfall, stony and dry soil conditions, or where the ground is frequently frozen or snow covered. Switches can be installed so that wires can be turned off if the situation warrants. For example, it is useful to put a switch on the wire closest to the ground, so that it can be turned off if there is too much vegetation on the fence line.

 

High-tensile fences are made with smooth wire that is pulled to an initial tension of 250 pounds. They require strong corners and end braces to achieve adequate tension. The wire is held on fence posts with staples. These staples are driven at a slight angle off of vertical so the slash cut points steer the staple into different grains of the wood. The staples are not driven tight against the wire, but instead allow freedom for the wire to move during tensioning, temperature changes, or livestock pressure.

Grounding
Poor grounding is the leading cause of electric fence failures. An electric fence must be properly grounded so that the pulse can complete its circuit and give the animal an effective shock. It is important to follow manufacturer's instructions for grounding electric fences. A minimum of three ground rods should be used for each energizer. It is estimated that 80% of electric fences in the U.S. are improperly grounded. A voltmeter is an inexpensive tool that measures the charge the fence delivers and can be used to trouble shoot electric fence problems.

The charger
The charger (or energizer) is the "heart" of the electric fence system. It converts main or battery power into a high voltage pulse or "shock" as felt by the animal when it touches the fence. In the past, electric fence chargers shorted out easily. Today's chargers are low impedance, meaning they are designed to effectively shock though vegetation and other foreign materials touching the fence.

A 4,000 volt charger is usually sufficient for sheep. The number of joules needed depends on the length of the fence, the number of electrified wires and the severity of conditions. A joule is the amount of energy released per pulse. As a general rule, 1 joule will power 6 miles of single fence wire; 4.5 joules is usually adequate for 20 to 50 acres. Lightning strikes can damage energizers. Surge protectors and lightening arrestors are recommended to minimize energizer damage.

High tensile electric fencing requires periodic upkeep. Fence wires should be kept properly tensioned. Weeds and brush should be cleared from the fence line by spraying or mowing.

It is important to note that an electric fence much more of a psychological barrier rather than a physical one. Sheep and lambs must be trained to respect electric fence. Once trained, they will usually respect the fence even if it is off for any reason. 



Woven Wire (American Wire, Page Wire)

Woven wire is the traditional type of fencing for sheep. It consists of horizontal lines of smooth wire held apart by vertical wires called "stays." The distance or spacing between horizontal line wires may vary from as close as 1 1/2 inches at the bottom for small animals, to as wide as 9 inches at the top for large animals. In general, the spacing between wires gets wider as the fence gets taller. Stay wires should be spaced 6 inches apart for small animals and 12 inches for large animals.

A four-foot high woven wire fence, with one to two strands of barbed or electric wire along the top of the fence makes an excellent perimeter fence for sheep. A strand of barbed wire along the bottom of the fence will serve as a "rust" wire and extend the life of the fence. 

An electric "offset" wire at shoulder height will keep sheep from poking their heads through the fence. Another offset wire, approximately 7 inches up from the ground will help to deter predators that try to go under fences.

High tensile woven wire fences are more expensive but will not sag or stretch as readily as standard woven wire. They are more resistant to rust and are considerably lighter in weight. Less fence posts are needed with high tensile woven wire.

The advantage to woven wire fences is their effectiveness as a visual barrier. Their biggest disadvantage is their cost. 



Mesh wire

Mesh wire fences have smaller openings than woven wire fences. Two types of mesh wire are the diamond mesh, which uses two wires twisted together in a diamond formation with 2-inch x 4-inch openings, and the square knot mesh, which has single horizontal lines with the wire spaced 2 to 4 inches apart. Because they are more expensive than woven wire, they tend to be used for confinement fencing, such as corrals and barnyards. 

Barbed Wire Fences
Barbed wire fences are generally not recommended for sheep because they may not effectively deter predators and they can cause injury to livestock. Sheep can get their wool snagged in the barbs. Barbed wires should not be charged due to their poor conductivity and safety for the animals. 

When barbed wire fences are used they should contain at least 5 to 6 wires, preferably 8 to 10 closely-spaced wires with several twisted vertical stays. The best use of barbed wire is to rejuvenate old fences or enhance woven wire fences. It is common to install 1 or 2 strands of barbed wire along the top of a woven wire fence and/or one wire along the bottom of the fence. 

Rail Fencing (wood or vinyl)
Rail fencing will generally not contain sheep or repel predators unless electric wires are placed between the boards or the entire fence is covered with woven or mesh wire. Rail fences are expensive to build and maintain. On the other hand, permanent, wooden fences are often used for corrals and barnyards. 

Other Types of Fencing
Fences made from hog wire or chain link, while effective are generally too expensive to enclose large parcels of land. They work well for corrals and barnyards and other high pressure areas. 

Rejuvenating Old Fences
Old fences can last many more years by attaching offset brackets and an electrified wire on each side of the old fence. Single off-set wires should be set at two-thirds of the height of the animals to be controlled. The old fence can serve as the ground wire and will work well to complete the circuit and control the sheep. 



Fence height
Fences can be built at different heights. Commercial fencing products come in different heights. Most predators climb, go through, or go under fences, as compared to over them.

Fence Posts
There are many types of fence posts. Fence post selection should be based on the specific fencing need. For example, treated wood posts are best for permanent boundary fences, while steel or fiberglass posts are suitable for temporary fences. Wood posts are highly variable in size and shape. Strength of wood posts increases with top diameter. Post strength is especially important for corner and gate posts, which should have a top diameter of at least 8 inches.

Brace posts should be 5 inches or more in top diameter. Line posts can be as small as 2 1/2-inches in top diameter, although larger diameter posts make fences stronger and more durable. T-posts and landscape timbers can also be used for line posts. 

Steel posts offer a number of advantages. They are lighter in weight, fireproof, extremely durable, and relatively easy to drive. They also ground fence against lightning when in contact with moist soil. Fence posts must be long enough to accommodate fence height, depth of setting, and an additional 6 inches. One of the advantages of high tensile fencing is that it requires less fence posts. 

Most fences use a post spacing of 8 ft. whereas the line spacing on high tensile fences varies from 16 to 90 feet. Post spacing needs to be adjusted for topography, livestock pressure, post size, wire tension, and use of poly spacers, battens, or droppers. 

Estimated construction costs for fencing (based on 1,320 feet, ¼mile)

Type
Total cost
Cost per foot
Woven wire, 1 barbed strand
$1,987.09
$1.51
Barbed wire, 5 strands
$1,613.65
$1.22
High tensile, non-electric, 8 strands
$1,483.75
$1.12
High tensile, electric, 5 strands
$927.13
$0.70
Electrified polywire, 3 strands
$309.69
$0.24

Source: Estimated Costs for Livestock Fencing, Iowa State University, updated 2005.



Wire
Wire may be galvanized steel, aluminum, or aluminum clad steel. Several gauges and breaking strengths of wire within the different wire types are available. Steel wire is covered with zinc, commonly called galvanizing, to protect it from rusting. More zinc means more years of service before rusting starts. 

High tensile wire typically carries three times as much zinc coating as barbed or woven wire, which accounts for its long expected life. Aluminum wire is lighter, more conductive, and never rusts; however, the breaking strength of aluminum wire is only about one third that of steel wire. A combination of these two materials is also available as aluminum clad hi-tensile steel. This is a hi-tensile steel wire with aluminum coating in place of galvanization. This wire has the high breaking strength of steel wire and the conductivity of aluminum.

12.5 gauge wire is usually the wire of choice for most permanent fences, while lighter gauges can be used for internal subdivision fences, both permanent and temporary.

Insulators
Insulators are a fundamental component of any electric fence. They are made from a non-conductive material, such as porcelain or plastic and form a barrier between the electrified wire and its support material to prevent current leakage to the ground. Plastic insulators are the most common type of insulator used on electric fences. They are cheap and easy to fit. 

Porcelain insulators have the best insulation properties, and if good quality, are the strongest. They are the most expensive. Plastic tube insulators are useful for taking a line wire around a post. Off-set insulators are used to attach a wire to a new fence or a non-electric fence. Cut-off switches are used to isolate parts of a fence without the need to turn off the energizer. 



Temporary fencing

Different materials can be used to construct temporary electric fences: high-tensile wire, polywire, polytape, and electric netting (or net fence). 

High-Tensile
Light weight, high-tensile wire (17 or 19 gauge) is most suitable for semi-permanent fences that will not be moved constantly. Two or three wires is usually sufficient to control sheep and lambs.

Polywire and Polytape
The most common materials used for temporary fencing are polywire and polytape. Both are combinations of metal and plastic filaments. Polywire has the appearance of heavy cord or plastic baler twine. It comes in several colors or combinations of colors. Several grades are available depending upon the number of filaments and gauge of the conductor. Most polywire sold is either 6 or 9 strand. 

Polytape similarly comes in several options and should be purchased on the basis of the number of filaments and the quality of the plastic weave. Compare to polywire, tape has the advantage of greater visibility, which leads to quicker animal recognition and training to the fence. Polywire is less expensive and lasts longer. Poly products come in reels with various capacities and with different locking systems. If you plan to move a fence, reels are an absolute necessity for polywire and polytape. 

Step-in posts

Plastic step-in posts are the most common line posts used with poly products. They are the easiest to use, especially if the fence will be moved frequently. The pre-molded loops provide plenty of flexibility for wire spacings. The metal re-bar posts are cheaper and last longer than plastic or fiberglass posts. They require insulators to hold the wires and can be difficult to get in the ground when the soil is hard. 

Fiberglass posts

Fiberglass posts are best suited to situations where the fence will not be moved frequently. Drive caps are usually used to hammer fiberglass posts into the ground. A spent shotgun shell also works well Wire clips or plastic insulators are used to hold the wire in place. All types of posts can be difficult to install during the winter. 

T posts

Metal “t” posts are stronger and last longer than the other temporary posts, but they cost more and require more labor to install and remove. 



Electric Netting

Electric netting combines traits of net-wire and electric fencing, providing a formidable mental and physical barrier in a portable format suitable for temporary or semi-permanent fencing of pastures. It is constructed of polywires and plastic twines. It is usually supplied in fixed lengths of 50 or 25 meters with support posts already installed. 

Netting is lightweight and easy to install. Compared to other temporary fences, electric netting provides greater protection from predators. However, with electric netting, there is some risk of animal entanglement, especially young lambs and animals with horns.

Comparison of fencing types

 

Type
Pros
Cons
Best use
Barbed wire
May already exist on property
Safety
Stock control
Predator control
In combination with woven wire
Woven wire
Visual barrier
Predator control
Cost
Installation
Entanglement
Permanent
Perimeter 
Holding areas
Stock panels
Visual barrier
Strength
Cost
Installation
Corrals
Holding areas
Mesh wire
Visual barrier
Cost
Installation
Perimeter
Holding areas
Board
Split-rail
Vinyl
Physical barrier
Aesthetics
Cost
Installation
High maintenance
Stock control
Predator control
Estates
Farm entrance
High tensile,
non-electric
Long life
Installation 
Cost
Predator control
Perimeter
Corrals
Holding areas
High tensile
electric
5 to 7 strands
Long life
Installation
Cost 
Predator control
Maintenance of fencelines
Permanent
Perimeter
Interior
Polywire
2 to 3 wires
Cost
Installation
Short life
Predator control
Interior 
Temporary
Polytape
2 to 3 strands
Cost
Installation
Short life
Predator control
Interior 
Temporary
Electric
2 to 3 wires
Cost
Installation
Predator control
Interior 
Temporary
Electric netting
Visual barrier
Installation
Cost 
Entanglement
Short life
Interior
Temporary
Small areas
Chain link
May have materials
Visual barrier
Predator proof
Cost
Installation
Corrals
Holding areas

November 22, 2013

Fencing Management

Introduction

Fencing is the key to pasture management. It allows a livestock producer to rotate pastures and control livestock and predators. Many types of fences are used in Ontario to provide a physical barrier. they include an assortment of cedar rail, stone, page wire, barb wire, suspension, hihg tensile, and board fences.

Livestock farms need at least an exterior or perimeter fence. Interior fences allow a farm to be subdivided and moveable fences add flexibility to grazing management. Electric fencing offers this versatility and is effective and inexpensive.

Electric Fencing

Electric fencing can replace worn out fences or be used as a new fence. It will support and extend the life of a page wire or rail fence. The high cost and labour involved in putting up and maintaining traditional fences has made electric fencing more attractive. When properly constructed, modern electric fencing is much more dependable than the older style battery-operated units used in the past.

Figure 5-1. One strand high tensile wire supporting a rail fence.

This image shows one strand of high tensile wire holding together a rail fence by being wrapped around the poles of the fence.

Training

Electric fencing is a psychological, rather than a physical, barrier. The success of electric fencing depends on training your livestock to respect the fence. Try the following:

  • keep your training area small
  • place a charged wire inside a permanent corral or barnyard fence, where there is little chance for escape
  • leave your livestock inside this area for a few days to familiarize themselves with this electric fencing before putting them out pasture.

Untrained, an animal may try to go through the fence. But many hours of time can be saved rounding up livestock and repairing fences if the animals are well trained.

How Does It Work?

A power source, either hydro or battery operated, is needed to operate the energizer. The energizer sends out a current in a pulse. Wire is used to carry the current along the fence. A ground completes the circuit. When an animal comes in contact with a live wire, it shorts the current to the ground and the animal receives a shock. An electric fence line with no vegetation touching it requires very little power to maintain high voltage levels. Normally the fence will have to handle some plant growth. This is called the fence load. Every plant in contact with a live wire draws a small amount of current to the ground. With miles of wire, this power drain can reduce your fence's effectiveness.

November 22, 2013

17 Mistakes To Avoid With Electric Fencing


By Wayne Burleson email: rutbuster1@mcn.net

With 30 years of experience building hundreds of miles of smooth-wire electric fence, I've seen just about every fencing mistake possible. And I continue to see folks make many of the same common mistakes. I still make mistakes myself, because I'm constantly challenging myself to make fencing easier, faster, stronger, and safer. 

High-tensile, smooth wire, electric fencing is the fastest and most affordable fence that I know about, and its technology has drastically improved over the past 10 years. But many folks are hesitant to use it because they remember old failures -- wires breaking, chargers starting fires, wet vegetation shorting out the fence and other troubles.

With a little commitment and a modest investment in time to learn how to use this new technology, you can save thousands of dollars and hours of maintenance time by making electric fencing work for you. So you won't have to learn the hard way, here are 17 common mistakes that you should avoid:

red ballPoor earth grounding. Lots of folks (including me) still think you can skimp when it comes to adequate earth grounding. What we must all learn to do, is install several ground rods -- at least three that are 6 to 8 feet long, galvanized, and attached with good ground clamps. The electricity must complete a full circle back to the charger through the ground. Poor grounding gives weak shocks. 

red ballUsing different types of metals. Don't do it. When you hook up steel wire to copper something call electrolysis happens and the metal becomes corroded, making a poor contact and weakening shocking power. 

red ballInadequate animal training. Each and every animal must learn that the fence hurts. So please build a handy training fence, preferably on heavy wet soil. Flag the fence for visibility, and force the animal to try and cross the fence. 

red ballFenceposts too close together. Well-intended government agencies recommend lots of fenceposts in their fencing specifications. Fifty-foot spacing on flat land is just too close. You want the fence to act like a rubber band. When something runs into the wire, you don't want to break all the insulators or knock posts out of the ground. If the posts are spread apart far enough -- say 80 to 100 feet -- the wire will just bend to the ground and pop back up. 

red ballToo many wire tie-offs. Again, fencing specifications may call for braces every quarter mile wire to tie the wire off. But I have found that even 5,000 feet is OK, and actually adds more elasticity in the fence wire. This reduces the chance of wires breaking.

red ballWires tied tight to each fencepost. To maintain elasticity (the rubber band effect), wires must float past each line fencepost. 

red ballBuilding new fences near old existing fences. Old fence wires seem to be always moving somewhere and coming in contact with the new electrified wires. This almost always causes a complete short in the fence, and away the animals go.

red ballBottom wire in contact with heavy, wet vegetation. Wet grass will suck lots of juice out of any fence charger. Hook up the lower wires separate from the other wires, and install a switch for the lower wires that you can turn them off when the grass is tall. 

red ballPoor-quality insulators. Be careful here. Sunlight deteriorates plastic. So buy good-quality, long-lasting insulators. Usually black ones are treated to resist degradation by ultraviolet light. I have found that poor quality insulators turn white or clear after a few years in direct sunlight. 

red ballStaples driven in all the way. When using plastic tubing as an insulator, don't staple it too tight. I once spent several hours trying to find a short in a gate. Finally, I discovered a staple had damaged the tubing next to a ground wire, causing a hidden short. 

red ballSolar panels not directly facing the sun. This seems almost too obvious to be a problem. But a solar panel won't function at its potential if not properly installed. Please read the instructions. Don't just guess if you have done it right. 

red ballKinks in high-tensile wire. A small kink in stiff wire will always break. Also avoid hitting this kind of wire with a hammer, as this will easily damage the wire causing a break. Always cut out a damaged section of high tensile wire and splice it. Incidentally, I have found that a hand-tied square knot makes the strongest splice.

red ballInstalling in-line strainers close together. Wires will flip together once in awhile. If in-line strainers are installed one above the other, they will sometimes hook up. Separate in-line strainers by a fencepost and they will never catch on each other. 

red ballWires too close to each other. Keep them at least 5 inch apart. 

red ballNo voltmeter. Without a voltage meter to check how hot a fence is, you're just guessing. 

red ballWire too small. The larger the wire, the more electricity it will carry. Don't skimp.

red ballInadequate charger. A wimpy fence charger gives you a wimpy fence. Don't skimp here because animals will think a smooth wire fence is a joke without a strong bite, and they'll walk right through it. 

Your fence charger should be low-impedance, come from a dependable supplier, and have a warranty and replaceable components. Please buy one that puts out lots of power. During a rainy year, you may have lots of plant growth touching the wires. That's when you will need extra power to shock through the heavy, wet vegetation. It's also handy to find folks with an extra charger they can loan to you while yours is being repaired. Expect some breakdowns, especially from lightning. Certain fence suppliers offer lightning protection with their warranties. 

Don't be afraid to try electric smooth wire fencing. Find a good fence suppler and learn some of the tricks of the trade. I know folks who hate electric fencing. But their pocketbook is not big enough to build a conventional fence, which may cost up to $1 per foot. 

The next time your bulls get in a fight with the neighbors bulls and tear down all the fence, remember that most animals will learn not to touch a wire with 5,000 volts running thorough it.

November 21, 2013

Electric fence installation guide

 

http://www.valleyfarmsupply.net/Articles/install%20guide.htm

November 21, 2013

The basics of electric fencing

Introduction

Whether you're trying to keep livestock from roaming off of your property or trying to keep pesky deer out, an electric fence is the ideal solution. When installed properly, an electric fence will generate a mild shock to discourage the animal from venturing through the fence. While installing an electric fence is not an overly difficult job, electricity is involved so extreme care must be taken. Before you attempt to install one on your own, please read this article and check the Tips and Warnings found at the end.

Instructions

Difficulty: Moderately Challenging

Things You'll Need

  • Electric Fence Controller
  • 10 to 14 Gauge Wire Insulated for 20,000 Volts
  • Grounding System (copper or galvanized rods and brass clamps)
  • Electric Fence Posts
  • Insulation Wrap
  • Post-Hole Digger
  • Hammer
  • Screwdrivers
  • Wire-strippers
  • Pliers

Steps

1

Step One

Find a weather-resistant location for your electric fence controller. This can be under an overhang or inside your basement or garage. Wherever you decide to place it, make sure that there is an available 120 Volt polarized outlet (an outlet where one blade slot is slightly larger than the other). Install the electric fence controller, but do not plug it in yet.
2

Step Two

One grounding rod will need to be installed within 20 feet of the electric fence controller. The grounding rod should be at least six feet long (all of it underground) and made from copper or galvanized. Run a grounding wire (10 to 14 Gauge, 600V to 20,000V) from the controller to the grounding rod and use the grounding clamp to secure the wire to the rod. Ensure that the clamp bites through both the wire and the rod.
3

Step Three

For the best grounding system, install two more grounding rods spaced 10 feet apart and reaching six feet underground. Daisy-chain these rods to the grounding wire as well. Check the Warnings Section below for more information about grounding rods.
4

Step Four

How you install your fence posts will be determined by how much land you are protecting. If you have a farm or other large parcel of land, then you will want to space your posts between 25 and 75 feet apart. Use the post-hole digger to make the installation quicker and easier. The distance between posts ensures that if something runs into the wire, there will be enough flexibility that it will not cause the connections to break.
5

Step Five

With the fence posts installed, it is time to install the wiring. Start your wiring with the farthest post from the electric fence controller. Make sure to use proper splices and tight connections throughout. Wrap your connections with insulation wrap to help reduce corrosion.

The common height for an electric fence for horses is 48 inches. With fences this high, it is best to run wires closer together (about six to eight inches apart) near the bottom of the fence to prohibit smaller animals from getting in. The wires from the middle to the top of the fence should be spaced about 10 inches apart. One wire should be set at shoulder height of the animal to be contained.
6

Step Six

When each post is wired, use an insulated length of 10 to 14 Gauge, 20,000 Volt wire as a jumper to connect each of the rows of wire. For instance, connect a jumper wire from the top wire to the second, from the second to the third and so on.
7

Step Seven

Now that the fence wires are connected, make your connection from the electric fence controller to the top wire of the electric fence. Once your connections are made, go back and re-check all of your connections along the fence. Do this before applying the power. When you are finished, insert the electric fence controller's plug into the available polarized outlet. There should be a light on the controller that will light up to notify you that the fence is working properly.
8

Step Eight

Once your installation is complete and the fence is electrified, use a voltmeter to check voltage along the length of the fence to ensure the electric is flowing the entire length.

Tips & Warnings

  • Place "Warning: Electric Fence" signs as often as you need, so from any vantage point one is easily seen
  • Educate family and friends how to safely disconnect the electric fence in the case of an emergency
  • Check your electric fence thoroughly every year for signs of damage, poor connections or poor insulation
  • Avoid installing your electric fence grounding system within 50 feet of any utility grounds, underground telephone lines or water pipes.
  • Do not use standard household electric wire. It is only rated for 600 Volts
  • Avoid using barbed wire
  • Do not add any other pieces of equipment to the circuit dedicated for the electric fence
  • Do not "tie in" any equipment to the electric fence field controller
  • Only fuses rated for 1 Amp/250 Volts should be used for the electric fence
  • Avoid adding a second fence controller on the same fence at the same time
  • Avoid standing near the electric fence during a lightning storm
  • If you are using metal fence posts, ensure that the wire DOES NOT come in contact with the post

Please order online 24/7 or call VALLEY FARM SUPPLY at 717-786-0368

November 21, 2013

How to Select, Install Electric Fence

How to Select, Install Electric Fence
Advice from an electric-fencing expert on selecting and installing it for maximum security and safety for your horse. Plus, a maintenance checklist for you.

When you need to build a new fence or replace an existing one, there's a major reason for using electric fence: Properly selected, installed and maintained, it's the most effective way to safely contain your horse. It's also economical and easy to install and maintain. Let's look at the basic components of an electric fence and how to avoid common problems.

 

Key Electric Fence Components
Charger. Sometimes also called an energizer or fencer, the charger needs to be powerful enough to deliver a definite jolt when your horse touches it, even when its current is reduced by vegetation touching the fence line or (as sometimes happens) by moist, dewy early-morning conditions.

Ignore chargers whose power is rated by miles; look instead for one rated by joules, a measure of the oomph with which the charger is pulsing its thousands of volts of current through the fence once every second. One joule is a minimum rating for fencing that encloses up to five acres, but I always recommend getting the most powerful charger you can afford. A higher joule rating doesn't mean the fence's jolt--which can't injure horses or other animals--will be harder or more painful, but that it will be more consistent.

The difference in cost will be insignificant compared to the value of your horses and your peace of mind; expect to pay $100 to $120 for a good one-joule charger that plugs into an outlet in the barn or elsewhere; six-joule chargers now sell for less than $200, a small premium for peace of mind. (Worried about your electric bill? Fence chargers use negligible amounts of power, whatever their rating.) I recommend solar-powered chargers--about three times as expensive as the plug-in type--only for paddocks where 110-volt power is unavailable; as well as delivering relatively low power for their cost, they're susceptible to failure.

It's possible to run insulated cable up to 1/4 mile from a charger to the fence without significant power loss. Install the charger under cover (except for solar-powered chargers, of course), where you can check it easily during each day's routine. Most chargers have a light that flashes with the electric pulse when they're plugged in and functioning.

Ground system. This is a series of three 6-foot-long, galvanized-steel rods pounded into the ground 10 feet apart and connected by insulated cable (see below) to the "ground" terminal on the fence charger. (In areas where soil is very dry, more than three rods may be needed.) Assuming that you have a good charger, the ground system is the key to your electric fence's effectiveness. If your horse touches the fence, he feels a jolt only when the brief pulse of electric current that goes through his body and into the ground is picked up by the ground system and returned to the fence charger, completing the circuit. Be sure to use a ground rod clamp to attach the ground wire as tightly as possible to the rod, rather than just wrapping it around.

Insulated cable. The cable that carries the electric pulse from the charger to the fence needs to be specifically for electric fence, with insulation rated for up to 20,000 volts (most fence chargers emit from 5000 to 10,000 volts)--the same degree of insulation as on automobile spark plugs. By using cable designed for electric fence, you avoid the electricity leakage that results when you connect the charger to the fence with heavy-duty household electric cable, whose insulation is rated for only 600 volts.

When attaching the cable to the fence itself, use a connector clamp rather than just wrapping the cable wire around the fence; cable connected by wrapping comes loose more easily or loses power due to oxidation or corrosion buildup. All fence manufacturers sell a connector clamp designed to work optimally with their product. You'll also need the cable to carry the electric fence current from one side of a gate to the other: Connect all strands of the fence to the cable on the side of the gate nearest the charger.

My preference is to then run the cable above the gate via an archway high enough to safely admit horses and paddock-maintenance equipment, but most people prefer to run the cable underground. That's fine as long as the cable is encased in waterproof plastic tubing, plugged at each end with silicone caulking and buried in an 18-inch-deep trench to protect it from damage by hooves and equipment. On the far side of the gate, use connector clamps to attach all strands of the fence to the cable.

Cut-off switch(es). Save lots of extra steps by installing a weatherproof knife-type cut-off switch (sold in the electric fence section of farm stores) between the insulated cable and its attachment to the fence, enabling you to turn the fence off without going back to the barn to unplug the charger. I also like to install cut-off switches on both sides of a gate--multiple cut-off switches allow you to isolate sections of the fence for easier trouble-shooting.

The fence itself. Visibility is key to an electric fence's effectiveness and safety. Materials such as 1.5- or 2-inch poly tape, braid, rope or coated HT wire make the fence easy for your horse to see and avoid. (Thinner fence materials such as poly wire or 1/2-inch poly tape are suitable for temporary installations or as a "hot wire" to keep horses away from solid fence; uncoated electrified wire--although dangerous when used as a fence material on its own--can also be used to protect solid fence.)

Choose a product with a long warranty (for instance, some fence materials have a guaranteed lifetime of 20 years) and follow the manufacturer's recommendations for number and spacing of strands. A good general rule of thumb is four to five strands of fence, 4 to 4.5 feet high, for perimeter fences and three to four strands for interior fences. Space the top two or three strands no more than 12 to 14 inches apart and the lower strands 18 inches apart, with the lowest strand 18 inches from the ground to minimize interference by grass and weeds.

Insulators. The type of insulator you need (to hold the fence material on the post that supports it, while preventing the fence from contacting any surface that will cause current to leak) is determined by your choice of electric fence; most manufacturers market insulators specifically suited to their fence products. In general, braid, rope, and coated wire are installed on insulators that allow the fence to slide through. To help prevent chafe and wear on a tape fence, however, insulators need to be the type that clamps and immobilizes the tape (especially important in windy areas), and to be installed vertically on the fence post. Avoid cheap "generic" insulators (often made of brittle plastic), which only last a few years.

Testing, Testing... Why It's Important
When your electric fence is built, monitoring its voltage regularly--I recommend daily--is a basic management practice, just like checking water buckets. Use a digital voltmeter that tells you exactly how many volts of current are on the fence. (How many volts are enough? Four thousand to 5,000--remember, there's no way this jolt of current can hurt your horse, but it needs to be definite enough for him to remember it and want to avoid it.)

Your first check of your new fence's voltage gives you a baseline so that future checks can alert you to voltage drops that signal problems. Depending on the strength of your charger, it will emit 6000 to 10,000 volts when nothing is connected to it. After you've hooked it to your fence, check the voltage at the furthest point from the charger. Some drop in voltage--1500 to 2000--is normal. A more than 2000-volt drop means either your charger is underpowered for the fence, vegetation or something else is "loading" the fence (touching it, causing voltage to leak away), there's a short-circuit somewhere in the system--or a combination of these.

If the base voltage on your newly built fence is 4000 or better and everything's working fine, watch on subsequent checks for an overall voltage drop of 1500 or more. (It's normal for voltage to be 500-1000 lower in the morning when moisture on the fence, posts, and nearby vegetation can cause temporary current leakage.) Such a significant decrease means it's time to check for problems and correct them before your horse discovers the fence no longer packs a punch; in fact, many horses can sense when the fence is or isn't functioning.

 

Electric Fence Maintenance Checklist
  • Look for and remove sources of "load." Mow or trim under bottom strand to prevent grass and weeds from touching the fence; watch for fallen limbs or other objects on the fence or caught in insulators. (Tips: Listen for the rhythmic snap that indicates a voltage leak; follow your ears to find the source. Drag a long stick on the ground beneath the bottom strand as you walk the fence-line; it may knock away an interfering object you don't even see.)
  • Check insulators. A broken insulator can allow the fence strand to touch the post--not an immediate problem with a nonconductive wood post, but if you're using steel T-posts a broken insulator can cause the fence to go dead when the strand touches the metal.
  • Check connections. Ground-rod wires can get knocked or kicked away. Wires attaching the cable to the fence may come loose.
  • Check the charger. A spider's web built between terminals can cause it to spark.
  • Check insulated cable. Look for places where the cable may be abraded, for instance where it passes through a hole cut in metal barn siding.
  • Check fence strands: Look for frayed spots in poly tape--if metal fibers in the weave become separated, tape can't conduct current.

Texas-based international fence authority Bob Kingsbery grew up on a family-owned horse-breeding farm; he has written widely on electric fencing and has conducted more than 300 seminars on fence technology and grazing management throughout the world. You can reach him with your electric-fence questions via email at bob@kingsbery.com.

 

This story originally appeared in the March 2004 issue of Practical Horseman magazine.


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November 21, 2013

How to Build High Tensile Fence

How to Build High Tensile Fence

Building your High Tensile fence

You have already decided what kind of fence you need, now the next step is to determine where you will put it. Be sure of your boundaries, check local laws and regulations pertaining to fencing and locate any potential hazards, both natural and man-made, such as underground utility lines and overhead electric wires. Make sure the fence path is clear of brush and debris. Once you're ready, install all end and corner posts. Next, run out a single guide wire to help assure a straight fence line. This wire will become the bottom wire of the fence and serves as a guide for setting the line post.

Attach the guide wire to both end posts. Use a chain grab wirepuller or an in-line strainer to pull the guide wire taut (about 100 pounds tension). For safety's sake, wear appropriate clothing, heavy leather gloves and eye protection when working with any wire fence and, when driving posts or operating other power equipment, wear hearing protection. If the terrain is hilly, drive the rise and dip post first and staple the guide wire to them before setting the line posts.

Setting the post(s)


Check the chart, which gives suggested post space distances for the type of fence that you are building. In most cases, the use of Kiwi Droppers® will allow you to reduce the cost by increasing the distance between posts.

Posts, small end down, can be mechanically driven with a hydraulic post driver or set using an auger-drilled pilot hole and rammed into place. Posts can be handset but driven posts have about five times the holding strength of handset posts.

If you hand set posts for brace assemblies, set the end post in concrete to keep it from uplifting. Dig the hole with a bell-bottom. Before you place the post, hammer a ring of staples, driven half way in, around the end of the post about 2 inches from the bottom. Place the post and tamp in tightly 8 inches of dry concrete mix. The soil moisture will cause it to set up. Fill the remaining hole with tightly tamped dirt to ground level. For gatepost, add an additional 8 inches of dry concrete mix 18 inches from the top of the hole. Fill the hole with dirt to ground level, tamping tightly.

To prevent overturning a post in soft soil and lifting of a post in a dip, increase the post length and drive deeper; again, check the chart.



Brace assemblies

The ASAE (American Society of Agricultural Engineers) recommends a double brace end assembly for American soil conditions. A double brace is rated at 9,000-lbs. pullover resistance and is more suitable for longer runs and larger livestock. Single brace assemblies can be used for fences of six wires or less. You can increase the holding ability of a brace assembly by increasing the length of the top horizontal post. Recently, a new double brace has become popular, which has the holding properties of a traditional double brace, but affords a cost savings in materials and labor. Drive a 6"x8' end/corner post but then use 4"x7' posts for the rest of the brace. The key is that the brace wire extends in a double wrap from the bottom of the end/corner post to the brace pin on the second brace post. To make the job neater, double figure 8 the brace wire.

 



Corners and changes in direction


A corner can be made using a common end post and building two brace assemblies at an angle from that end post. To reduce material costs, corners may be constructed using post leaning against the pull of the wire: For every 10-degree directional change, use a 4" x 8' post on a 4" lean, 4' deep; for every 20-degree change, use a 5" x 9' post on a 5" lean, 4 1/2' deep; for every 30-degree change, use a 6" x 9' post on a 6" lean, 5' deep. Drive the post by machine on a lean or to the bend. With either type of corner, string the wire to the outside of the bend, or any curve in the fence for that matter.


Stringing the wire

Once the line posts are set, mark them for the proper wire spacing, and string the remaining wires. A spinning jenny or multi-wire fencer will make handling the wire easier.

For electrification, slide on the required number and type of insulators. Staple the wire accurately to its mark at all corners, major dips and rises, and at the post next to where you will install the in-line strainers. These points will create some friction. The in-line strainers should be installed near the middle of these friction points.

To ease installation, attach a chain grab wire puller to the wire at least four feet from a post, pull out the slack, cut the wire and use crimping sleeves to secure the strainer. Thread the other end of the wire through the hole in the drum, cut off the surplus. With the handle turn the drum until no slack remains. Use one tension indicator spring for each set of in-line strainers.

Joining and tying off wire

You can join wire by manually tying a knot but a knot in the wire will reduce the wire strength by a minimum of 30%. It is better to join wire with a mechanical wire link or three crimping sleeves; both create a joint as strong as the wire. To anchor wire at the end, as in joining wire, you can knot the wire but you reduce its strength. The better way to anchor the wire is to use two crimping sleeves or drill holes into the end post and use a wire vise mechanism, which has a tapered barrel that firmly holds the wire.


Stapling

Before stapling the remaining line posts, tension the wire taut, about 100 pounds, using the in-line strainers. This will prevent crossed wires and aid in positioning the wire. To reduce pullout use 1 1/4 - to - 2 - inch long, 8 or 9 gauge slash cut, electro-coated galvanized staples with barbs. If you rotate the staple 30 to 45 degrees away from the flat face, you will prevent the post from splitting and the staple leg will spread, curving outward from the flat face for greater holding power. Drive staples at an upward angle into posts in dips and at a downward angle into posts on rises. The staple should allow the wires to move back and forth freely. Staple the wire to the livestock side but on the outside of corners and curves.


Tensioning the wire


One in-line strainer per wire can tension 4, 000 linear feet of high tensile wire on a straight-line fence over level terrain. To calculate the number of in-line strainers needed add 500 feet for each corner, severe dip, rise or curve to the total linear feet of your fencing project. Divide this total by 4,000, round the answer up to the nearest whole number (for example, 1.3 = 2) and multiply by the number of wires on your fence (2 x 6 wires = 12 strainers or two sets). Tensioning from the top wire down will provide clearance for turning the in-line handle. Use the wire with the tension indicator spring attached as a guide to tension the other wires. Pull the wire towards you and tighten until all the wires have the same "feel" (resistance). After a day or so the fence will set, check each wire and if necessary, correct the tension to the recommended 250-lb. pull.


Grounding non-electric fence

All fences utilizing steel wire on nonconductive posts must be grounded for safety from lightning. Drive a galvanized steel post, 3/4 - inch galvanized steel pipe or an approved ground rod at least 3 feet into the ground, not more than 300 feet apart (150 feet in dry, rocky soil). Attach 5 strands of galvanized wire to the rod and lace through each fence wire. Bend the top of the ground wire bundle into a loop and staple home to a post.

Electric fence

Your high tensile fence can be easily electrified using new high voltage, low impedance type energizers. The construction methods described for non-electric fences also apply to electric fences with one important exception. Energized wires must be insulated from the post; The need for insulation makes it necessary to plan for electrification before you begin construction. For specific help on energizer selection see Energizer guide.

November 20, 2013

How to Make A Well-Grounded (Earthed) Fence

Make A Well-Grounded (Earthed) Fence
Tips from a New Zealand grazing farmer and consultant to keep your fence hot and your livestock in.

By Vaughn Jones

Editor's note: Noted New Zealand grazing farmer and consultant, Vaughn Jones, has been building and troubleshooting electric fences since 1954. Here he provides a checklist of advice and tips to solve one of the most common causes of fencing failure: Poor grounding -- or "earthing" as they say "down under." 

For your fence to function correctly, your earth (ground) system must be perfect. But very few are, despite the instructions provided with most energizers. Also I've not seen an instruction book with complete details of how to achieve perfect earthing and completely trouble-free operation in all respects. So I'll give all I know here:

Most farms seem to have earth systems which can't cope with the flow of electrons coming back to it from fences with poor insulation, leakage into vegetation, and the occasional wire which breaks and touches the ground or touches a non-insulated wire. Energizers have become more powerful, but many ground systems and their recommendations have not kept up with them. 

When the energiser (charger) earth system can't handle the increased flow of electrons, they find other ways of getting back to the power supply earth system. Unfortunately they sometimes do this through the cows and milking machine, and through steel water pipes or the water in plastic pipes. 

Guide to Good Grounding 

When the energiser earth system can't absorb the increased flow of electrons from leakage, electrons find other ways of getting back to the power supply earth system. Energisers put out thousands of volts, and just one volt through the cow's mouth or teats can upset her. Here are methods to follow to avoid that:
  • The energiser earth system must be installed well away -- at least 10 m (33 feet) from mains power earth peg, preferably on the opposite side of the building.
  • Use 25-mm (1-inch) or larger diameter new or near new galvanised pipe driven as deeply as possible into a moist soil, each at least 10 m (33 feet) apart. Thin, black or rusty fence posts or similar are not suitable. Rust is a bad conductor. A large surface area is needed to give a large contact area between the soil and pipe.
  • One metre (3 feet) of earth pipe per joule of output of the energiser is usually sufficient for satisfactory earthing in conductive soils. Long earth pipes which are driven deep into the soil give far better earthing than the same total length at shallower depths because soils are more moist and have more conductive minerals at lower levels. Two 3- metre-long pipes are better than three 2-metre-long pipes when driven deeply this way. Large diameter pipes have a greater soil contact surface, so are better than thin rods.
  • Install the earth system well way from water pipes and bores which are being used. But an unused steel pipe bore can be an excellent earth if it's not rusted or broken.
  • Connect the terminal marked Earth or Ground to the earth pipes by one continuous length of double insulated electric fence leadout cable -- not household or industrial cables which are made for only 400 volts, not for 10,000 volts. The cable should contain 2.5-mm (16-gauge) galvanised wire -- not thinner and not copper wire, which causes electrolysis at the joins. Bare and clamp the cable securely to each pipe with galvanised clamps. Ordinary galvanized wire can rust where it is damaged or touches the ground. Using cable eliminates this.
  • It is best to have no voltage on the earth system, but a maximum of 200 volts (and up to 300 volts on a large energizer) are acceptable when the fence has been shorted out to as low a voltage as possible.
  • Soils are not good conductors, so electrons spread out inclining towards moist and mineral soils when travelling back to the energizer. Aim for a moist area, work out a system of keeping the area around the earth pipes moist. If necessary, take a galvanised wire along the bottom of a fence to a moist area, and then install more earth stakes at that point. If the distance exceeds 100 metres, use two wires. Better still, use aluminium or aluminium-coated wire which is up to three times more conductive than the same thickness galvanised wire.
  • Some soils are very bad conductors. If you have dry peat, pumice, volcanic ash soils, etc., or soils that are dry at any time of the year, and there is no wet area within a few hundred metres which could be used, a bentonite earthing system can be bought and used. They are a good value. The bentonite mix is made into a slurry and poured down 75-mm (3-inch) diameter or larger holes with pipes set in the centre. Keep them moist. This system can improve earthing by up to ten times.
  • In extremely dry areas and on snow, use an earth wire return system. This is where there is an equal number of live and earth wires kept well apart on the fence. The earth wires are joined with joint clamps (like the live wires) and connected to the energized earth terminal. The earth wires should also be earthed adequately (no voltage on them) every kilometre. These also act as lightning conductors, keeping it away from energizers.


Testing an Earth System 
 

  • Testing an earth system without the fencing shorted out is a waste of time. You must create a flow of electrons to load the earth system before testing it.
  • Also testing the earth by holding the last earth pipe can be a waste of time if the wire between it and the energiser is broken.
  • To test the earth system, first short the fence out with steel rods at least 100 metres from the earth system. Then use a digital voltmeter to measure the voltage between the energiser earth terminal and an independent earth wire. This should be pushed as far as possible (about one metre) into damp ground in a position handy to the energizer and several metres away from any other earth peg.
  • To lower the voltage on the earth system add more earth pipes and/or connect the earth wire to the bottom wire of a conventional fence.
  • Never use your water supply, bore or well as a ground or allow a charger ground wire to touch them or any part of buildings. It can cause shocks in the water and stop animals from drinking, and buildings can become a transmitting aerial for radio and phone interference.
  • Double insulated underground cable should be used for the ground as well as the live wire. Unused bore pipes or steel well liners are usually good grounds.
  • Many New Zealand farmers measure Joules (energy) roughly by holding the live wire and feeling the kick in good insulated gumboots standing on one foot to halve the electrons flowing through your body. Caution: Don't do this if you have a dicky ticker or Pacemaker.
  • High-power energizers are essential for to controlling animals where long lengths of wire are electrified. The high power is on for the very short period of 0.0003 seconds which makes them safe.
  • Voltage measured at the energizer is useless, especially if the fence wire is thin, limited to one wire or has bad connections. But voltage can be an indicator of the energy when measured at the end of a long fence.
  • The latest, best New Zealand energizers have a system of telling the farmer at the energizer the effectiveness of the fence at various points, and the earth condition, both of which are extremely clever.
  • The lower the voltage on the ground the better it is. But with high-power energizers, it can be difficult to get the voltage below 200 volts, which figure is acceptable (provided it was measured when the fence was shorted (grounded) a few hundred metres from the energizer).
  • Ensure that all electrical appliances wirings, everything metal and all concrete steel reinforcing are all connected by welding or strong galvanised clamps, not electroplated ones which rust sooner.
  • If your stock are going through fences, check the earth first, followed by the joints on the whole fence, and at the same time look for shorts.
  • Test your earth by thoroughly shorting out the fence at least 100 metres (330 feet) away from the energiser with steel standards. Doing this creates the maximum current flow so puts a load on the earth system. If your earth pipes can't handle the flow you'll get a voltage reading at the energizer terminals. If there is no voltage, then your earthing system is satisfactory.
  • You should have a digital voltmeter, then install an earth monitoring point by pushing a piece of 4-mm (8-gauge) wire into the ground handy to the energiser and measure between it and the energiser earth terminal. Don't check the last earth pipe because there could be a break in the wire to it, in which case you'll think the earth is OK, but it may not be.
  • With the fence shorted out, there should be no more than 200 volts, although no voltage reading is best. The more voltage you read flowing to your earth, the less power you will have on your fence because it indicates that the earth is inadequate and needs more pipes.
  • To improve your earth system, increase the number of earth pipes and put them in as deep as possible. Tests on several soil types have shown that depth is essential -- 2 m (6 feet) deep is the minimum, and 3 m (9 feet) deep is twice as good.
Doing all the above reduces the chances of clicks on your radio and telephone. 

An inadequate earth system reduces the output of your energiser and increases the chances of shocks in milking parlors, yards and water troughs. It takes an expert with sensitive measuring equipment left connected for 24 hours and a recorder to check for shocks in parlors. There may be none during the day, but they can occur when heaters, cookers, etc., are switched on in the late afternoon. 

Check your parlor twice a year and yards in many positions at the height of dry weather and the height of the wet period. See your energiser installation instructions for more details on installing it and an earth system. 


Poor Earthing Costs Production 

A common problem is having energiser earth pipes behind the milking parlor. Leaked electrons (there are always some) flow from the farm under the yard and parlor when the soil is moist. But when it is dry, they look for easier routes, which can be across a moist yard and through parlor pipe work. 

In wet weather, electrons can travel along the soil surface and through the parlor, especially after cows enter and pass their high mineral, highly conductive urine. This can cause electrons to even flow across the concrete surface and across pipe work, so affecting the cows. 

A short or weeds conducting power off a live wire close to the parlor can result in electrons flowing through the parlor and/or yard because it is the shortest route, especially after cows enter and urinate. The above can occur even when the earth system is perfect, simply because the electrons are flowing to it via the best, shortest and fastest route. 

To avoid this, earth systems should be in a damp area well to the side of the milking parlor, or even have earth pipes well to both sides, but never in line with the parlor. The earth leadout wire from the energiser should be insulated, and not allowed to touch any other wire, building or pipe. 

Electrons can also move through water pipes, giving shocks to cows when drinking in a paddock, so no wires should be allowed to touch water troughs. Even if not electrified, they can conduct induced current. Cows standing around a full trough waiting to drink can be a sign of power deterring them from drinking. 

Where conventional fences have a live wire running with them or as an offset wire, the conventional fence wires can absorb induced current (more so in damp conditions) and become electrified. So unelectrified wires must be earthed or they can build up a voltage which can:
  • Jump gaps (bad joins) and cause sparks and radio and phone interference.
  • Conduct current to water troughs they may touch. Animals then won't drink so growth and milk production suffer, and females can get cysts on their ovaries through stress. This happened to a herd near here causes calculated losses of $30,000 over the years it had been happening.
  • Give people shocks when opening and closing gates.
  • Give animals shocks as they go through gateways and brush against the wires tied around strainer posts.
Earthing these conventional fence lines is easy because being induced power, it is of low joules (energy or power). All they need is a piece of soft galvanized wire wrapped around all dead wires at the strainer posts and pushed into the soil. These will need replacing when they rust at ground level. 

Shocks in sheds and water troughs have cost some farmers small fortunes in lost production over several years, until the problem was identified. New Zealand manufacturers discourage grounding the fence circuit though the earth or ground terminal of the charger to the utility (power supply) grounding system because it is illegal in many countries and can cause shocks in all directions including in your shower. The power supply ground is usually just a metre deep rod. A modern high power New Zealand energizer needs ten to twenty times more. 
 


Safety Considerations

Keep these in mind when you build fence:

  • Don't string wires across lanes or thoroughfares without marking them clearly. Motor cyclists have been injured through not seeing them.
  • Never electrify barbed wire.
  • Train and demonstrate the shock to children and visitors with a long piece of grass.
The thought of 5,000 volt fences on farms near cities could be frightening to townies, but thousands of human contacts occur annually with nothing more than discomfort. However, care should be taken to avoid contact through the head because it is very uncomfortable. Young children and elderly people should be kept away from even low powered fences. 

Electrified fences in any position where the public could come in contact with them must be clearly marked with approved warning signs at frequent enough intervals so as to be easily seen. 


Radio Interference 

It is an offence to operate any appliance which causes any electronic interference, so points to note include:
  • Some energizers cause more radio and/or phone interference than others, even if not on a fence. Switch it off, disconnect the fence and earth (ground) cables (wires) at the energizer (if they were loose the sparking there could cause interference) and switch on the energizer and check for interference.
  • If the interference is still there, return the energizer to the supplier and try another unit or brand. Some brands are bad.
  • If the interference disappears when the fence and earth are disconnected:

     
    • Tighten all joins and clamps on the energizer and fences. Those on some energizers work loose because of the thump (vibration).
    • Ensure that all wire connections are figure of eight or reef knots, or are clamped and tight.
    • Tube insulators will crack and leak in time. Even double tubes and those with steel inserts leak and spark in some cases.
    • Sparking causes radio and telephone interference so insulators must be good quality with adequate tracking distance to avoid arcing over the surface as occurs with staple insulators or through the insulator as occurs with single tubing. Use quality insulators with at least 25 mm (1 inch) of tracking distance (length on insulator from the live wire to any other point).
    • Some cable can have breaks in it causing sparking. Single insulated cable gets cracks sooner than double. (Try bending a sheet of cardboard and a wad of paper the same thickness and you'll see why. The card will crack.) Some of the orange cable from New Zealand cracked and leaked soon after installing. Replace it all.
    • Even the best cable when buried can become damaged by a stone and then leak. It is essential that all be threaded through 12 mm (half-inch) or similar black plastic piping to give it physical protection. If the distance is long, push a piece of high tensile wire (with its end bent back) through and then pull the cable through. To check under gateways, disconnect before each one and check if the interference stops.
    • Ensure that the earth is perfect. Check it at the energizer, not at the last earth pipe as shown on some instruction books. There could be a break in the cable so there would be no voltage at the last, or even first pipe.
    • The earth cable should be one continuous length of double insulated cable or be joined with a good galvanised joint clamp, and must not touch any building or pipe. Support the cable in good insulators.
    • Use a digital volt meter to test the earth and to locate shorts and maintain tidy, trouble-free fences.

       
  • If you still have interference, tighten all joins and clamps on the farm. This is best done in summer when joint clamps have expanded.
  • Walk along all fences and wires with a radio tuned off the station and clicking. It will get louder close to the interference cause.
  • Shorting to vegetation or to any grounded object can cause clicking, so disconnect the bottom wire and/or clear the fence line with a weed wiper. Once grass touches a live wire, stock won't graze it, or anywhere near it, so the problem increases. Always have the bottom wire able to be disconnected with a flexible connector and do so before vegetation touches it.
  • The mains power supply (utility) earth and all connections including power point terminals and plugs must be adequate with no loose or old verdigris connections.
  • If wires run parallel with overhead phone wires on underground phone cables interference can be worse, so avoid the constructing of electrified fences parallel to telephone lines or cables and aerials, or parallel to other long fences which could act as aerials.
You might find this difficult. Having changes in the fence to under-gate cable reduces the length of "aerial" electric fence wire. It is long lengths of electric fence wire parallel with long lengths of telephone or similar wires which cause the problem which can grow as the fences are extended over time. The closer they are the more the induction. The break causing the spark and interference can then be on the induced wire. 

Radio interference is worse in poor reception areas, and if the radio is not tuned exactly on the station. Telephone systems are not always perfect. 
 


Lightning Protection 

The long distances of electric fencing now used increase the chance of a lightning strike, so an effective protective system should be used. Lightning often hits the power supply line and goes through the energizer to its earth system blowing its fuse or components. The power (utility) supply earth system should be good enough to attract the lightning rather than have it go through the energizer to its earth.

Finding Shorts 

The solid state digital volt meter is important for fault finding and for testing the earth system. It enables accurate reading of the voltage and easy fault finding, because of its extreme accuracy. 

Start by going to the first switch (these must be installed along fence lines to save going back to the energizer to switch it off for repairs and for fault finding) and see if the voltage before the switch increases after opening the switch to stop current flow down the farm. 

If the voltage increases then go to the next switch. If not check the fence between the switch and the energizer. Neon fence testers are also available, but of no use for finding small leaks or earth system faults. Many are bought and not used for long before buying a digital volt meter.

Electric or power fencing helps make animal farming profitable and sustainable, so the effort required to achieve the above suggestions is well worthwhile. If installation is good and monitoring is done, the labour required is less than with any other system and the profit is greater. 

If you have problems, read all the above again. There is a lot to take in, but once you understand it, it becomes second nature. 

Take pride in your fencing and enjoy your animals.

Please order online 24/7 or call VALLEY FARM SUPPLY at  717-786-0368

November 20, 2013

Gallagher Gets Grizzly Bear

 

Got a problem keeping a few cows fenced in?  How about keeping a few hundred grizzlies fenced out?  Or making sure a few dozen black bears aren’t getting after your goats?

 

Bears of all kinds are a sometime dangerous nuisance around Yellowstone and Grand Teton National Parks and the national forests of northwestern Wyoming.  It’s a wilderness area bordered by Montana and Idaho that’s perfect habitat for a large and growing population of bears.

 

Bears are born scavengers that can get aggressive when they’re hungry.  Easily accessible campsites, apiaries and dumpsters are nothing more than convenient dining spots for these creatures.  When they decide to munch on whatever’s handy, they can do serious economic damage and threaten people as well as livestock.

 

Mark Bruscino is a bear specialist with the Wyoming Game and Fish Department.  Bears are his constant problem.  “They’re smart animals,: he said, “they’ll find a way to get around most preventative measures.  They can knock down barriers and tunnel under most fences.”

 

“We have to keep them out of grain sheds, small garbage dumps and dumpsters.  Most of the things we tried in the early 1990’s didn’t work,” he said.

 

In 1993 Morgan Renner, a Territory Manager with Gallagher, helped design an electric fence to solve the problem.  “I’m sold on it,” said Bruscino as he talked about the fence.  “It’s top notch stuff.”

 

The fence is “100% effective” when it’s maintained properly, according to Bruscino.

 

The Game and Fish Department uses permanent and temporary Gallagher fences now.  The permanent fences are where bears are a constant problem – around camp grounds, for instance.  Temporary fences can be quickly erected around sites like grain bins until the bear can be captured and transported to a remote location.

 

“We use a five-wire fence with high tensile strength wire.  Because it can be very dry, we use alternating hot and ground wires to make sure we’ve got full conductivity,” said Bruscino as he described the permanent set up.  Wooden corner posts anchor the fence and he uses fiberglass posts to support the wire.  The lower three wires are spaced six inches apart and the top two wires have 10 inches between them, making for a bear proof barrier.

 

Bruscino estimates bears have tested the fence hundreds of times without successfully breaking through.  “Usually, they just spin around and take off,” he said.  “I saw evidence that a bear swatted at the wire once but all it did was stretch it out a bit.”

 

To prevent “tunneling” bears from going underground, Bruscino uses a woven wire ground in some place.  Stretching about three feet out from the fence line, it’s additional discouragement to marauding beasts.

 

Bee keepers in the region sleep better at night and goat herds graze unmolested.  More importantly, campers can sleep safely at night, too, with nothing between them and the night air but a few square yards of canvas.

 

According to Gallagher, “An electric fence is a psychological barrier that keeps farm animals and wild animals where they should be with safety and security.  Because the fence is a psychological barrier, it doesn’t require great strength to be effective. However, it must be well designed in accordance with the species to be controlled, and constructed to withstand the harsh weather conditions that hit the Rockies in the dead of winter.”

 

Gallagher is one of the world’s largest manufacturers of electric fences designed to contain cattle, horses and other farm animals as well as prevent wild animals and predators from gaining access to areas where they can do economic damage.

Please order online 24/7 or call VALLEY FARM SUPPLY at  717-786-0368

November 20, 2013

2014 SOUTHEAST PA GRAZING CONFERENCE

2014 SOUTHEAST PA GRAZING CONFERENCE

Sponsored by Lancaster County Graziers.

Date: Tuesday, 18 February 2014 - Wednesday, 19 February 2014 Location: Solanco Fairgrounds | Hoffman Building | Quarryville, PA

Contact: Levi Fisher Phone No: 717-405-9438