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Home - Sensor Specs - Components - Ordering - Design Solutions - About NECAD - About IFS  - Contact Us


  1. General Description and Installation (Livestock & Security Design)

  2. Basic Design Considerations (Security Design)

  3. Specific Design Solutions (Security Design)

  4. Psychological Impact  (Security Design)

  5. Liability Requirements and Troubleshooting (Security Design)

  6. What makes an ordinary electric fence an extra-ordinary high security device (Security Design)


GENERAL DESCRIPTION AND INSTALLATION

There are several basic considerations and many secondary considerations in designing an electric fence. We shall discuss the primary considerations first.

NOTE:  When properly designed and installed, an electric security fence is the least expensive, safest, and most secure method for securing property, lives, and especially most livestock when compared to walls, other types of fences, human guards, and watch dogs. The fence does NOT sleep. The fence CANNOT be bribed. The fence does NOT require food or water. A well designed electric fence has more deterrence value than a guard with a sawed off shotgun or a snarling pit bull.

A well designed electric fence is the most "cost effective" method of securing property or pasture, as well as the most effective.

1. COST:  consider that any cost is too expensive if the fence is ineffectual, or just doesn't work. So then, you have to have, at the least, a minimally effective design, to justify the cost, or it isn't worth doing at all. Do it right, or don't bother.

   The "Sensor - Alarm" assures the integrity of your electric fence. It will alert you to voltage drop from weeks, brush, grass and that it is time for cleaning your fence.

   The "Sensor - Alarm" assures the integrity of your electric fence by providing an ALARM from voltage loss, from "cut", "shorts", or breaks in your fence.

   An Electric Security Fence can be designed to keep out predators, thieves, trespassers, vandals and disease. A well designed electric fence will keep your livestock safe and safely confined.

2. EFFECTIVENESS: An electric fence design to keep livestock penned in (or out) is no different. A simple wire or tape around the pasture or livestock enclosure is only done for a temporary enclosure. A more permanent enclosure requires the same design considerations as you would for security (although simpler). Security for your expensive livestock should be a prime consideration.

   An Electric Security Fence is designed to protect property, livestock, production, manufacturing, property, and lives. Every situation is different, but there are also some considerations that are the same, no matter who, what, or where.

   When designing your electric security fence, keep in mind the above statements and each individual item that applies. Also to "keep out" or to "keep in" or both are valid considerations.

   3. SECURE: The smallest effective fence extension for walls or chain-link fence for security consists of 4 strands where the top and alternate strands are connected to earth ground with the alternate strand to be charged The reason for 2 charged strands is to provide a security loop. You make the connections or the fence energizer to the outgoing wire and return on the other strand to be able to monitor the voltage and status of the fence. This ability to monitor the fence status and fence voltage is a critical factor on any electric fence

4. MINIMAL: The smallest effective fence extension for livestock consists of 2 strands. The reason for 2 charged strands is to provide a security loop. You make the connections or the fence energizer to the outgoing wire and return on the other strand to be able to monitor the voltage and status of the fence. This ability to monitor the fence status and fence voltage is still the critical factor on any electric fence. However, if you use a single strand (1 conductor) then the "sensor - alarm" should be connected to the farthest end of the fence from the high voltage charger.

   However, if you connect both the outgoing and returning ends to the charger, then, even if cut, the high tensile wire is charged from both ends, and you will not be able to detect a break or short in your fence. Security is then compromised. 

   The more secure design is, the returning high tensile wire is connected only to 
a high voltage monitor and alarm. It is mistakenly thought that it is best to connect the fence energizer to both ends of the fence conductor. This might be true if NO fence monitoring device is used.

   Therefore all electric security fences should have an even number of charged High tensile/voltage strands. EX: 2, 4, 6, 8, etc. strands. To provide a secure fence of any type the strands should be interconnected in an alternating fashion to provide a singe loop that is charged from one end and monitored from the far end.

   A voltage monitor attached to the very end of the charged loop will sound and alarm or siren if the wire is cut or shorted making a voltage loss. A more sophisticated electric fence monitor will also alert you to a lowered voltage to indicate the weeds and brush need to be cleared from your fence.  Although very few petty thieves will attempt to cut through the fence, the fence/voltage monitor makes the electric security fence into a very effective alarm sounding security device when tampered with. 

   If the fence is designed to make it very difficult to pass without a resultant shock, and when coupled with a voltage fence monitor becomes an extremely effective security system. The final determination will always be a balance to whether the additional level of security is worth the added cost of a voltage monitor.

   Grounded Strands: the high tensile strands should alternate with grounded strands. The grounded strands should be insulated exactly like the high tensile strands. If all the strands are insulated, the fence is perceived as much more lethal, and therefore becomes much more effective. If an intruder actually decides to cut a wire, not knowing which are grounded strands and which are charged strands makes the fence retain a higher security rating.

   A fence is designed with 3 or more strands. Usually, the top strand and the bottom strand are charged, however, there are some cases where a 4th grounded strand is added as the topmost strand to help ward of falling foliage, fronds, etc to help prevent the plants from shorting out the high tensile strands and creating "false alarms". 

   If the electric fence is constructed from ground level, then the bottom strand may be a grounded strand to prevent weeds and grass from shorting out the High tensile/voltage circuit. However, a concrete footer is a better design option with the bottom strand to be charged. 


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INSTALLING THE EQUIPMENT:


   The Components of your system should be installed and mounted inside and out of sight and LOCKED out of reach from unauthorized people.

NOTE: Make sure the fence charger switch is turned to the OFF position. Connect the battery charger to the battery and plug the battery charger into the utility voltage so that the battery is being continuously charged. Make sure that the battery charger is "current limited" or of the type that can be continuously connected to your battery without over-charging the battery. 

   Now connect your Earth Ground System  and all your ground return wires together, and then make the connection to ground connection on the fence charger. Use a minimum sized wire of 14 AWG or larger, in either solid copper or galvanized steel and make the connections with appropriate connectors. The most common cause of voltage failure or loss, is a poor ground or earth ground connection.

   Make sure you have a sufficient "earth ground" network. Always use a minimum of 2 ground rods 3 or more meters apart, and additional ground rods at least every 100 meters (300 feet). Do NOT connect the fence energizer ground to any household ground such as water pipes, well casings, etc. This could cause a dangerous condition in the case of lightening strikes on the fence strands.

   Finally make your high voltage connection to the fence using an appropriate connector with high tensile or spark plug wire with an insulation rating capable of carrying the high voltage with a large enough safety factor. When you run the high tensile wire to the fence charger make sure the high voltage wire is not laying on the ground, and is not running through water, and is not placed across sharp corners. Many installations use standard (14AWG solid) single strand wire fed through 1 or more thick wall plastic hoses.

   If you have purchased a fence monitor connect the end of your high voltage charged loop to the high voltage terminal on the monitor using the same high tensile wire that you used to connect the charger to the fence. Connect the Earth Ground System to the ground terminal of the monitor, or if desired connect to a solid earth ground network used only by the monitor.

   The fence monitor will continuously monitor the voltage on the fence. If an intruder cuts a wire, the fence monitor will close a set of contacts that can be reported to a monitoring facility and/or activate a siren alarm. On the more sophisticated monitors,  the grass, weeds, or brush when grown and partially shorts out the fence and lowers the high voltage, a separate alarm will be given to alert you that the fence should be checked and cleared.

   We strongly recommend a separate battery to power the monitor and siren, bell, or whatever alarm notification is connected to the fence monitor. The small extra cost of a small 12 volt battery that will feed your monitor and devices raises the security rating of your system at least another notch higher on the security rating scale.

   A High Voltage fence charger/energizer with a voltmeter that will also continuously monitor the voltage on the fence is a super "backup" device. If a branch or foliage is laying across the high tensile wire, and partially shorting it out, the fence voltage will drop and will indicate on the voltmeter on the energizer.

   We recommend that you check your fence at least once a week. Plant foliage, or branches or fronds laying across the high tensile wire might not reduce the voltage on the meter when dry, but foliage becomes a conductor when wet and might easily short out your system completely reducing the fence voltage to almost zero when soaked from rain.

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  1. General Description and Installation (Livestock & Security Design)

  2. Basic Design Considerations (Livestock & Security Design)

  3. Specific Design Solutions (Security Design)

  4. Psychological Impact (Security Design)

  5. Liability Requirements and Troubleshooting (Security Design)

  6. What makes an ordinary electric fence an extra-ordinary high security device (Security Design)

 

 


Home - Sensor Specs - Components - Ordering - Design Solutions - About NECAD - About IFS  - Contact Us

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NECAD, Inc. & Intelligent Fencing Systems, Inc.
Brandon, Florida