Electric Fencing Basics

  

All Speedrite Electric Fence Charger models output a wide pulse which puts the hurt in the pulse which gets and keeps the respect of the animals.  Don't be fooled by mileage ratings which are just an approximation of power but go by the electric joule power rating.

Parts to Electric Fence

Capacitor An output capacitor is used to store direct current (DC) electricity between pulses through a fence. Alternating current (AC) can’t be stored using a capacitor. Corner posts Sturdy wooden posts driven deep into the ground to provide extra support for the tension put on a fence line as it changes direction. Corner posts are not only used at corners, but also for gates and end posts. Direct-discharge fencer A type of fence controller that does not require a grounding system to deliver an electrical shock. Direct-discharge fencers are most effective on short, weed-free fences.

Amperage

The measurement of electric current.  Amperage is what you feel when you are shocked.  The higher the amperage the more intense shock you feel.

Battery Charger

A charger powered by a battery, usually 6V or 12V.  Used in remote areas where there is no access to a 110V outlet.  Can be used with solar panels that recharge the battery for added convenience.

Capacitive discharge

Describes chargers that store direct current (DC) in an output capacitor prior to discharging to the fence.  Most chargers are capacitive discharge.

Controlled Grazing

The management of forage with grazing animals.  Usually involves dividing pastures into smaller paddocks with electric fencing and moving the livestock frequently.

Direct current (DC)

Type of electricity that is produced by batteries and can be stored (as in a capacitor).  Most fencers produce direct current.

Energizer

Another name for a fence charger.

Fencer, Fence Charger, Fence Controller

An electrical device that produces electrical energy and delivers it to a fence for the control of animals.

Ground rod

Metal stake driven into the soil that picks up electricity moving through the earth from the charger.

Ground rod clamp

Device used to connect the ground wire from the charger to the ground rod.

Ground System

The electrical path back to the charger.  Usually an earth-ground system using ground rods in the soil.

High tensile

An affordable, long lasting electrified fence system that is an excellent choice for perimeter fences, providing a barrier to contain or exclude animals. These sturdy, permanent fences require braced corner and end posts in wood along with special insulators, hardware, and tools that maintain constant high tension on metal wire.

Hook-up Wire

Insulated wire rated at 20,000 volts (or more) used to make electric fence connections without voltage loss.

Insulator

Device used to keep an electrified fence wire from coming in contact with posts or anything else that would interrupt the flow of the current through the fence line.  Usually made from plastic or porcelain.

Joule

The measurement of energy used to rate low impedance fencers.  1 joule = 1 watt of power for 1 second of time

Line posts

A post used to support electric or non-electric fence wire. Line posts support the fence line, and have far less tension put on it than corner posts. As a result, they can be made from a variety of materials, including metal, wood, plastic and fiberglass.

Low-impedance

A type of electric charger that can increase its output energy as fence load increases.  Delivers high amperage shocks in very short pulses.

Ohms

Ohms are used to measure resistance to the flow of an electric current. A high ohms reading indicates a light fence load, while a low ohms reading indicates a heavy fence load.

Permanent Fence

A multi-strand, well-braced fence traditionally made from barbed wire and/or woven wire and now made from electrified high tensile wire.

Portable Fence

An electric fence that is easily moved.  Also known as a temporary fence.

Rotational grazing

A system for allowing livestock to graze, using internal temporary enclosures (within a boundry fence) to control the particular areas where the animals can graze. This allows the vegetation in the previous enclosures to grow back. Usually is 1-strand of wire at 40" or at animal's nose level.

Solid state

Solid-state fence chargers deliver a medium amperage shock in pulses of medium duration. They are best used to control shorthaired livestock, small animals, and pets where light weed conditions exist.

Splicer

A device that joins separate strands of fence wire without breaking the fence's electrical circuit. Tensioner A component used to tighten fence wires, typically polytape, to increase tension on a section of the fence line.

Voltage

Measurement of electrical pressure.  Voltage “pushes” amperage down the fence wire.  The higher the voltage the more amperage it can push.

Watt

Measure of electrical power.  Voltage x Amperage = Watts.  Watts x Time = Joules.

Distance ratings 

A way of comparing the relative power of fence controllers. Ratings are based on a single strand of 17-gauge steel wire strung 36 inches above the ground under ideal, weed-free laboratory conditions. 

High tensile 

An affordable, long lasting electrified fence system that is an excellent choice for perimeter fences, providing a barrier to contain or exclude animals. These sturdy, permanent fences require braced corner and end posts in wood along with special insulators, hardware, and tools that maintain constant high tension on metal wire. 

Insulator 

A nonconductive material (plastic or ceramic), typically used to offset fence wire from a fence post. Insulators prevent the current from traveling through the post and into the ground, short-circuiting the system. 

Line posts 

A post used to support electric or non-electric fence wire. Line posts support the fence line, and have far less tension put on it than corner posts. As a result, they can be made from a variety of materials, including metal, wood, plastic and fiberglass. 

Pulse width 

Pulse width refers to the duration of the electrical pulse produced by a capacitive discharge fencer. 

Resistance 

Resistance is any force that resists the flow of electricity, consuming power from a circuit by changing electric energy into heat. Electricians measure resistance in ohms. 

Solid state 

Solid-state fence controllers deliver a medium amperage shock in pulses of medium duration. They are best used to control shorthaired livestock, small animals, and pets where light weed conditions exist. 

Temporary fencing 

A one to three-strand electric fence system that is used for rotational grazing or other short-term uses. It typically uses step-in poly posts or rod posts, and a DC or solar operated fence controller for portability and flexibility.

Grounding
Most electric fence problems are caused by poor grounding. Why? An electric fence is an electrical circuit. The electrical current travels from the charger, down the fence line, through the animal, along the earth to the ground system and back to the charger. If the ground system is inadequate, the electrical current is reduced and the animal receives a weaker shock.


 

how to use an electric fence fault finder


Most electric fence problems are caused by poor grounding. Why? An electric fence is an electrical circuit. The electrical current travels from the charger, down the fence line, through the animal, along the earth to the ground system and back to the charger. If the ground system is inadequate, the electrical current is reduced and the animal receives a weaker shock.

Tips -

• The ground system should be at least 33' (10 m) away from electric or telephone ground systems to avoid interference.

• Moist soil conducts electricity much better than dry soil. If possible, locate the ground system in a boggy area. In dry weather, wet the area around the ground system to keep the soil moist.

• Make sure there are a sufficient number of ground rods. See your charger’s user manual for recommendations. If in doubt, use at least three ground rods. Use more ground rods if your soil conditions are not ideal.

• Ground rods should be at least 6'6" (2 m) long. One long ground rod works better than several short ground rods.

Testing your ground system

Test your ground system regularly to ensure you are getting the most out of your electric fence.

1. Turn off the charger.

2. At least 330' (100 m) away from the charger, short circuit the fence by laying several steel rods (or lengths of pipe) against the fence. In dry or sandy soils, it may be necessary to drive the rods up to 12" (30 cm) into the earth.

3. Turn on the charger.

Note: Do not short circuit a fence-return (ground-wire-return) system by connecting the live wire to the ground wire.

4. Use a digital voltmeter to measure the fence voltage. It should read 2 kV or less. If not, add more ground rods.

5. Check the ground system by inserting the voltmeter’s ground probe into the earth at the full extent of the lead, and test the voltage on the last ground rod. The voltmeter reading should be no more than 0.3 kV. If the reading is higher than this, your ground system is insufficient. Add more ground rods, or find a better location for your ground system.


3. Faults

Faults are caused when the electric current leaks away from the fence down to the earth. This is often caused by grass, weeds or overhanging branches touching the electric fence. Broken insulators may cause a fault by allowing the electric fence wire to touch the fence post. Check your fence regularly using one of the procedures below.

4. Checking your fence

Using a fault finder is the quickest, most accurate way of locating a fault in the fence. Starting at the leadout wire, work your way along the fence taking readings at regular intervals. A fault will show up as an abnormally high reading. The electrical current flows towards a fault in the same way that water flows towards a hole in a punctured hose. A sudden change in current between one point and the next indicates a fault between the two points.


It is also possible to check for faults using a digital voltmeter. Isolate sections of the fence using cut-out switches and check the voltage in each section.

An AM radio can be used to locate a fault. Tune the radio between stations and drive or walk along of the fence. If the fence is OK, there won't be any sound. When the radio gets near a fault, you will hear clicking on the radio. As you get closer to the fault, the clicking will get louder.

If the fault is caused by a faulty insulator, mark it with non-metallic paint so you can locate it easily after you have turned off the fence.

5. Joins

Electric fence wire should be joined using a knot that allows the electrical current to pass through the wires. Here are some recommended knots:

electric fence electric fence electric fence
To join broken poliwire or politape, use a cigarettle lighter to burn away the plastic yarn in order to expose the stainless steel wire. Twist and join the wires together, then tie the poliwire or politape in a knot. The electrical current can then pass through the join. When inter-connecting fence wires at the end of a strain, use joint clamps. Using these clamps, instead of twisting wires together prevents arcing and greatly reduces voltage loss.


6. Undergate connections

When bypassing gateways, ensure that live wires are protected from damage caused by animal hooves, vehicles etc. Encase high quality, double insulated underground cable in a polythene pipe and bury at least 12 inches (30 cm) deep. Turn the ends of the pipe down to keep water out.

7. Animal training

To train animals to respect electric fencing one method is to use a small well-fenced holding paddock. Divide the holding paddock using Politape and a Patriot charger. Introduce the untrained livestock to the paddock. The animals will quickly learn to avoid the electric fence barrier.

8. Choosing an electric fence charger

Make sure your electric fence charger meets the requirements of your electric fence, refer to your Patriot installation manual for guidance. This will vary depending on the type of fence, the number of fence wires, how much vegetation is growing around the fence and the climate. Remember, if you extend the length of the fence by adding to the fence or subdividing it with temporary fences, you need to make sure your charger is powerful enough. If you use a more powerful charger, make sure you increase the number of ground rods in the ground system.

9. RFI (Radio Frequency Interference)

Many farms suffer from RFI (Radio Frequency Interference. This often results in poor radio reception and an annoying ticking noise on the telephone line. Patriot chargers are fitted with special components and advanced circuitry that significantly reduces the levels of electrical emissions that might otherwise affect adjacent electrical equipment. .

10. Mixing metals

Avoid using different metals in your electric fence. In damp conditions, when an electric current passes through the differing metals, electrolysis will occur. For example, using stainless steel ground rods and an aluminium leadout wire will cause problems. In a short space of time, the aluminium will disintegrate. If possible, keep the wire joints above the soil to improve airflow and reduce electrolysis. Seal the wire joints with thick paint, epoxy or tar to keep moisture away from the joint area. Use identical metals in your electric fence will avoid problems with electrolysis altogether.

11. Getting a shock from a fence post or gate?

Sometimes, induction causes a strainer post or metal gate, giving whoever touches it a nasty shock. To overcome this problem, staple a piece of wire onto the strainer post to interconnect all the fence wires. Bury the wire 3" (10 cm) into the earth. This will carry the unwanted current down to the earth. Because the interconnecting wire is positioned after the insulators, you will not be compromising the quality of the fence in any way.