Electric Fencing

Goats can be very frustrating when it comes to fencing them in. They are smarter than sheep and can therefore get into more trouble. it is very important that you build a fence that is both secure and safe. There are many choices when it comes to fencing. The big thing to remember is to never, never use sheep fence as that will be the death knell of many goats. They get their heads stuck and if you don’t find them soon enough, they are sure goners. Many goat grower prefer to use electric fencing. Why Electric Fencing?

Permanent electric fencing costs much less than conventional fencing. It is important to realize that a fence no longer represents a physical barrier to livestock, but is a mental barrier. This simple fact enables big savings in the construction and maintenance of the electric fence. When an animal comes in contact with the electric fence, it receives a shock because it has short-circuited the current from the live wire to the ground. Once an animal is shocked by a fence, it will not challenge it again. This prevents wear and tear on the fence itself. There is no need to repair that old conventional fence again. After proper installation, your new electric fence is virtually maintenance free.

Safety – In the high powered, low impedance energizers, the pulse lasts no longer than 3/10,000 of a second. After that, there is no voltage until the next pulse, one second later. Using high voltage is not dangerous, provided that the pulse has a very short duration. Even though the body is strongly affected by a pulse, the delay of one second between pulses is sufficient to recover and retreat from the fence. When purchasing an energizer it is wise to check that it complies strictly with the safety standards to eliminate any danger. All energizers that do comply with these safety standards are clearly marked on the label.

Installation – Energizers contain no moving parts and are not gravity sensitive. They are weatherproof but are vulnerable to moisture. Keep the energizer in a weather protected area (on the down wind side of a post) mounted at eye level and out of harm’s way. Always keep the energizers clear of vegetation and away from any low lying areas where water may puddle. The terminals are marked on the energizer, so connect the wires accordingly. The earth terminal is green and the fence terminal is red or yellow. Always use insulated wires when connecting the energizer to the fence and the earth rod. This prevents any corrosion and chance of shorting. Consult your dealer for the proper wire type and size for your specific application. The AC powered energizers should be mounted 4 feet from a power outlet that provides 115 volts AC. These energizers have two keyholes on the top that make mounting to a wall or post very easy. The 12 volt battery operated energizers can be installed anywhere along the fence. They come with stands, but can also be mounted on a wall or post.

Grounding the Controller – Poor results in electric fencing are directly due to faulty grounding of the controller. If the earth surrounding the farm is not continually damp all year round, then a wire earth-return system ensures the delivery of optimum shock anywhere along the fence line. The controller, however, must have a separate ground regardless of whether a wire earth-return system is used or not. The ground must be at least two meters away from any other ground system. For example, a power or telephone wire always uses an independent ground. A suitable ground would be 2 to 3 eight-foot lengths of galvanized pipe/rods driven into the earth and then wired to each other with secure connections at each pipe. To prevent any corrosion problems, use only insulated galvanized wire with proper clamps between the controller and the ground rods and galvanized insulated cable onto the fence earth-return wire. The ground site may be some distance from the controller, particularly if this provides a more effective grounding system. The importance of a good ground connection cannot be overstressed.

Methods of grounding – The majority of problems with electric fences arise from inadequate grounding arrangements that prevent the energizer from functioning properly. The ability of the ground to conduct electricity is dependent upon its composition and condition. Very dry, sandy ground can be highly resistive while wet, rich earth can be quite conductive. As a result, the method used to obtain a satisfactory earth-return to the energizer has to be tailored to suit the prevailing conditions.

A. Method One – In areas that have sufficient rainfall throughout the year to support continuous pasture growth the ground moisture content will give a satisfactory earth-return to the energizer provided a good earth system is constructed in the vicinity of the energizer. Typically, 8 feet of 5/8 inch diameter galvanized pipe is required to provide a satisfactory ground for a permanent fence installation and if possible, should be located where the ground is always wet. In the event that you are unable to drive the entire 8 feet earth stake, you may cut the pipe into three equal lengths and hammer those into the ground leaving sufficient pipe protruding to enable galvanized pipe clamps to be attached. The three pipes must be spaced at least their own length apart. Wire all three pipes together using clamps and bolts. Without cutting the wire, take it straight to the earth terminal on the energizer. Preferably, all items used (clamps, bolts, wire nuts) should be galvanized to prevent corrosion. Corrosion is greatly aided by moisture and so a good sealing compound should be used to prevent water Tom getting into the wire connections. This is imperative if copper wire or any other dissimilar metal is joined together. The avoidance of corrosion is necessary simply because the life of the connections would be shortened and also, corroded joints storm a partial blockage to electric current, therefore reducing the performance of the whole installation. Position the ground wire so that stock or machinery will not damage it. If your earth system is disconnected, the electric fence will be ineffective.

B. Method Two – If your soil has poor conductivity, it will be necessary to add one or more earth-return wires to the fence. It should be noted that the wire return system does not replace the earth-return system described in Method 1, but is additional and required by dry soil conditions. Under this system, touching the live wire and the ground wire simultaneously causes the main portion of the shock received by the animal. As the earth return wire is connected to the earth terminal of the energizer, the circuit is completed by that double contact. Some residual shock is still delivered through the earth. It should be noted that the earth-return wire should be individually grounded to the earth in various locations throughout the fence (depending upon the length of the fence) to ensure good grounding of the energizer throughout the fence line. The earth-return wire should be uninterrupted entirely down the fence line as in Figure 1. A suitably insulated wire should be buried at all gateways.

How to Check the Earth System – To check the efficiency of your earth system, switch on the energizer, touch one of the leads of the fence tester to the ground as far away from the earth rod as the fence tester wire will allow, and clip the testers’ live connection to the earth rod. The fence tester should read zero. If not, you need to drive another earth rod and wire it to the others. Do so until the voltage reading is zero.

IMPORTANT: The more current supplied by the energizer, the greater is the need for metal required in the ground to collect and return it to the energizer.

Safety Regulations: –

  • Do ground the fence energizer at least 8 feet from any power grounding. The reason is, if a power appliance becomes faulty but does not blow a fuse, you could get 120 or 240 volts continuously on your fence.
  • Install an electric fence warning sign where the public may come in contact with the fence at least every 330 feet.
  • Use only high quality UV resistant insulators when wood or steel posts are involved in your fence line.
  • Do not pulse more than one energizer on the fence at any one time.
  • Do not erect fences or earth wire near overhead power wires, telephone wires or radio aerials. This will cause interference. It must not be possible for the fence line or the earth wire to come in contact with power or telephone wires.
  • Do not use barbed wire on an electric fence.
  • Fault Finding – If the voltage of the fence line is low, follow the following three-step procedure

    A. Step One

  • Check to see if the indicator light is flashing or listen to hear if the unit is clicking. There should be a click or a flash every second.
  • Disconnect the energizer from the fence wires and determine if the energizer is operating correctly. Check the fuse.
  • Check the output voltage with an approved electric fence voltmeter.
  • If the energizer gives full output voltage when disconnected, the fault lies in the fence. Generally, the lower the output when connected to the fence, the closer the fault lies to the unit. The output current of the energizer is such that there can be a dead short a mile away and yet the voltage at the energizer may be several thousand volts due to the impedance of the fence. Faultfinding is made much easier by installing cutout switches periodically in the fence line to allow isolation and testing a fence section at a time.

    B. Step Two – Check your earth (ground) connections to ensure that all connections are clean and free from corrosion. Check your earth system as described above.

    C. Step Three – Disconnect the first section if the fence is installed with cutouts.

  • Check the output voltage of the section with the energizer switched on.
  • Reconnect the section.
  • Proceed on to the next section until an incorrect voltage reading is obtained.
  • Examine that fence section for obvious faults. Possibilities may be an odd piece of wire tangled in the fence, broken insulators, or fence that is down.
  • It recommended that you carry a nonconductive rod or bar made of fiberglass or plastic as you walk the fence line and drag the rod between; the bottom live wire and the ground. Often time, vegetation will conceal a foreign object. Do not suspect vegetation growth unless it is extremely heavy for a distance along the fence. Beware of odd pieces of wire that could be hidden in the undergrowth. The electric fence voltmeter will assist in locating a fault. The lower the voltage reading the nearer the fault. If the fault is caused by metal, there will be a zero voltage indicated at the site.

    Finding Fault with a Battery Unit – If you are receiving no voltage at the energizer or the energizer is not working:

  • Check the battery condition and
  • Ensure that battery connections are free from corrosion. With 12-volt batteries, it takes very little corrosion to stop current flow. This is the most common source of trouble with battery operated energizers.
  • Check the connection to the fence.
  • Check the fence line and earth connections as explained in the first section of fault finding.
  • Grounding – Make sure sufficient rods are used on the fence. Poor energizer performance can be traced to insufficient ground in many instances.

    Fence Design – The emphasis on height is not as important with electric fences as it is with conventional fences. Wire spacing and appropriate post spacing to insure sustained wire spacing. It is much more important. See your dealer for advice tailored specifically towards the goals of the ranch. Never run two or more energizers into the same section of fence. Poor performance and damage to the energizers will result. If more than one energizer is required on a fence, be sure there is a complete break between the systems

    Energizer Protection – When an energizer is operating on the same circuit as a high-energy demand device such as an arc welder, irrigation pump. etc., always disconnect the energizer when that device is in use. An excellent time to disconnect and energizer and the wires to and from the earth and ground is during a lightning storm.

    Feeder Cable – Use sufficient conductor wire from the energizer to the fence line to avoid that section becoming a resistance point. Copper has better conductivity that high carbon steel and is recommended for all connections of live and ground wires. Be sure to use compression sleeves and taps on all connections

    When a fence is not working, first suspect the fence. Many energizers get sent in for repair when there is nothing wrong with them. If you do suspect the energizer, do not attempt to repair it yourself. The telltale clicking or light blinking will say if the energizer is working. Check the fence and the power supply first.

    Copyright 1994 Capricorn Press. Not to be reproduced without express written consent of Capricorn Press. Contact Info@CapCas.com for more information.

    Leave a Reply

    Please log in using one of these methods to post your comment:

    WordPress.com Logo

    You are commenting using your WordPress.com account. Log Out / Change )

    Twitter picture

    You are commenting using your Twitter account. Log Out / Change )

    Facebook photo

    You are commenting using your Facebook account. Log Out / Change )

    Google+ photo

    You are commenting using your Google+ account. Log Out / Change )

    Connecting to %s