Installation andOperation Of

Electric Fences,Cow Trainers and

Crowd Gates

A SELF-HELP GUIDE FROM…

Midwest Rural Energy Council

Table of Contents

Introduction ........................................................................................................................ 1

Electrical Circuits and Energizers ................................................................................. 2

Selecting an Energizer ..................................................................................................... 4

Building an Earth-Return System ................................................................................. 6

Connecting an Energizer to a Fence ............................................................................ 7

Lightning Protection ........................................................................................................ 9

Cow Trainers..................................................................................................................... 11

Crowd Gates ...................................................................................................................... 12

Insulators, Posts & Safety Tips .................................................................................... 13

Acknowledgements & References ................................................................................ 14

Checklist for each Energizer......................................................................................... 15

Introduction

Electric fencers, cow trainers and crowd gates have been usedon farms for many years to help manage animals. These de-vices are designed to produce avoidance behavior when the

animal comes into contact with an energized object. Electric fencingtechnology has progressed over the years resulting in safer devicesand improved animal control in both grazing and confinement sys-tems.

Like any technology, however, if not installed properly or not usedcorrectly, problems can occur. One potential problem is fencer shocksappearing in unintended locations. Field studies in Minnesota, Wiscon-sin and Australia have shown that improperly installed fencer systemsare a common cause of short duration transient voltages in unin-tended locations on dairy farms.

This publication provides a review of the basic electrical conceptsof fencer operation as well as guidelines for installing safe and effec-tive electric fencer systems. Recommendations are also providedregarding fencer and trainer operation and maintenance. The informa-tion is presented in a question and answer format and is designed toaddress common questions and problems encountered by users andinstallers of these devices.

1

Electrical Circuits & Energizers

How do energizers work?An energizer converts 120-volt

electrical power or power from abattery into high voltage, shortduration electrical pulses. Theseelectrical pulses typically range from2000 to 20,000 volts with durationsof 1/1000 to 3/10,000 of a second.These short duration pulses maycause avoidance behavior but are notharmful to the animal.

There are two different electricalcircuits involved in the operation of atypical energizer (Figure 1). Thepower circuit (60Hz) carries 120-volt

electrical power from a service panelto the energizer. Most fencers areplugged into a receptacle. As with anyelectrical circuit, the electric currentmust flow in a loop.

The current path for the farmpower circuit is out through one 120-volt (hot) wire and back on theneutral wire. The primary function ofthe grounding system is to conductfault current and quickly operateprotective devices.

The second circuit is between theenergizer and the fence. The low

voltage power coming into the ener-gizer is converted to very shortduration electrical pulses. The ener-gizer pulse flows out through the highvoltage lead-out from the energizer tothe fence only if an animal or some-thing else touches the wire to completethe circuit back through the earth.Once the current is in the earth itflows to an earth-return rod and earth-return wire back to the energizer. Theenergizer circuit is the same forbattery powered energizers, except a120-volt power circuit is not used.

2

What is the differencebetween an earth-returnrod and a ground rod?

An earth-return rod is like anantenna that collects the highvoltage energizer current from theearth and returns it to the energizer(Figure 1). The EARTH MUST bepart of the return path of a fencercircuit. The earth-return part of thecircuit is active only when an animalor other conductive object com-pletes the electrical circuit bytouching the energized wire.

A ground rod (also shown inFigure 1) is meant to be part of adifferent circuit. The purpose of thegrounding system is to protectpeople, animals and the farm wiringfrom contact with lethal voltagefrom the electrical power system.Ground wires are designed to carryfault current back to the trans-former so that circuit breakers cantrip or fuses blow and shut offpower. Electrical faults are causedby shorts, or an unintended contactbetween a 120-volt (hot) wire andany conductive object. The EARTHCANNOT be the sole return path forelectrical system fault current.Ground rods are designed to keepcontact voltage on the grounded-neutral system below harmful levels.

It is important to separatefencer earth-return rods from thefarm grounding system so thatfencer pulses will not appear inundesirable locations on thegrounded-neutral system.

What is the most commonreason for failure of anelectric fence, cow trainer orcrowd gate?

Improper earth-return systems arethe most common cause of energizerproblems. Two common installationproblems are undersized and improperlylocated earth-return systems. Tips oncorrect installation will be covered laterin this publication.

How can an improper earth-return system cause “strayvoltage”?

An inadequate earth-return systemcan cause the energizer pulse that goesout on a fence to find other routes backto the energizer. If the earth-return wireis connected to a metal building orpipes, they can become part of thereturn path. Any conductive object,such as an electrically heated watertrough can become part of the returnpath if the earth-return system is notproperly installed.

What is the most importantthing to remember aboutseparating the fencer earth-return and farm groundingsystems?

The two grounding circuits aredoing two different things and shouldnot cross paths. The energizer’s earth-return system needs to complete thefencer circuit and return HIGH VOLT-AGE, short duration fencer pulses tothe energizer. The farm groundingelectrodes should keep the grounded-neutral system at a LOW VOLTAGEwhile ground wires provide a lowresistance path for fault current back tothe transformer.

The HIGH VOLTAGE of the ener-gizer and earth-return circuit mustnever come in contact with the LOWVOLTAGE grounding circuit. If thesetwo circuits are connected, the ener-gizer pulses may occur in undesiredlocations.

Interconnection can occur either onthe hot or return parts of the energizercircuit. High voltage insulation must beused on the high voltage lead-out wirefrom the energizer to make sure that theenergizer pulse does not leak ontoconductive objects, such as metal wallmaterial and metal pipes. To preventinterconnection on the ground side ofthe circuit, make sure that there is plentyof separation between earth-return rodsand any grounded object. This includesthe ground rods and any other objectconnected to them such as equipotentialplanes, grounded metal conduit, andgrounded cases of electrical equipment.The recommended separation for earth-return rods ranges from 50 to 150 feetdepending on the soil conditions. Use themaximum available separation distanceespecially in areas with wet, heavy soils.

Electrical Circuits & Energizers

“The HIGH VOLTAGEof the energizer andearth return circuitmust never come in

contact with the LOWVOLTAGE farm

grounding circuit.”

3

Selecting an Energizer

Selecting an energizer can beconfusing because manufac-turers use different terminology

for ratings for their devices. Lets havea look at some energizer terminology.

What is a low impedanceenergizer?

Low impedance energizers (alsoreferred to as “New Zealand” styleenergizers) produce extremely highvoltage but very short durationelectrical pulses. These high voltage,short duration pulses lose less energywhen objects such as grass or brushcome into contact with the energizedwire. This allows low impedanceenergizers to be effective on longerruns of fence. A good earth-returnsystem is essential to make sure thiselectrical circuit functions properly.

How are energizers rated?There are two common ways that

energizer output is rated. The first isthe number of miles of fence that theenergizer can power. This is not a veryaccurate rating system because of thevariability in soil resistance and theamount of unintentional contact bygrass and weeds with the energizedwire. An energizer rated at 25 milesof fence will not necessarily be effec-tive on 25 miles of fence under allconditions but it will have moreoutput than an energizer rated for at15 miles of fence.

The second energizer ratingmethod is the energy output, orjoules, in each fencer pulse. This isalso only a relative comparison; not all5-joule energizers are exactly alike.

Two 5-joule pulses may have differenteffects on animals because of differingvoltage level and pulse duration.

So how much power shouldmy energizer have?The required power of the energizerwill depend on

the area to be fenced,the number of wires energized,the type of animal being controlled,use of higher resistance temporaryfencing andweed pressure.Provide a reputable energizer

dealer with a description of yourintended task, and it is likely that therecommended energizer will be sizedcorrectly. Using a more powerfulenergizer than required increases thelikelihood that the fencer pulses willoccur at unacceptable levels and/or inunintended locations.

What is the best energizervoltage?

For most situations an outputvoltage between 2000 and 6000 voltsis optimal. Most domestic animals willrespect a properly installed low

impedance fencer that is over 2000volts. An energizer that delivers10,000 volts is not necessarily moreeffective than a 6000 volt model.Some energizers that deliver more‘energy’ or joules are actually lowervoltage. The key to making anyenergizer work correctly is properinstallation.

Should I use the same voltagefor a fencer and cow trainer/crowd gate?

No! Do not use energizers in-tended for fencing inside buildings.They deliver far too much energy andincrease the likelihood of problems.Higher voltages should only be usedfor electric fences. Voltages for cowtrainers and crowd gates never beabove 2500 volts.

Can I use the same groundrod for a fencer and a cowtrainer?

No! Each energizer must have itsown earth-return system. The groundrods return current to the energizer tocomplete the energizer circuit. Eachenergizer should work on its’ ownclosed loop circuit.

“Provide a reputable energizer dealer with adescription of your intended task, and it is likely thatthe recommended energizer will be sized correctly.”

4

Why are energizers used forcow trainers and crowd gateseasier to size than those usedfor a fencer?

The barn environment does notvary from farm-to-farm as much asfence length, soil conditions, earth-return distance and earth resistance infencer applications. The range ofdesign variables is thus much largerfor fencer applications than for crowdgates and trainers.Where should I install theenergizer?

Although it may be more conve-nient to place fence energizers in abuilding, it is safer to install theenergizer outside. Locating theenergizer outside and some distancefrom buildings will eliminate the need

to install lead-out wires with specialhigh voltage insulation through thewalls of a building. Outside installa-tion will also make it easier to sepa-rate the energizer earth-return circuitfrom the farm grounding system.

When installing an energizeroutside of a building make certain it israted for outdoor use. Adding someprotection from the weather willincrease an energizer’s life. Keep theenergizer at least 10 feet from anybuilding to help protect the buildingand its wiring from lightning strikeson the fence wire.

How should power besupplied to the energizer?

Energizers can be powered bybatteries, solar, 120 volt or 240 volt

AC power. If you are using a 120-voltAC unit plug it into a three-wire 120-volt receptacle wired in accordancewith the National Electric Code. TheNational Electric Code specifiesseparate neutral and groundingconductors from the point of use tothe service entrance panel. A surgesuppression receptacle or single plugsurge suppressor is strongly recom-mended.

What about the UL rating?Buy an energizer with a UL

rating. There are many energizersmanufactured outside of the UnitedStates that are not UL approved. TheUL rating will ensure that the devicecomplies with the NationalElectric Code.

Selecting an Energizer 5

6

Where should an earth-returnsystem be located?

As discussed earlier, an earth-return system is like an undergroundantenna for picking up the electriccurrent that is sent out on a fence byan energizer. Place the earth-returnrods inside the perimeter of the fencedarea if possible and well away (50 to150 feet) from any other conductiveobjects buried in the earth (e.g. waterlines, ground rods, and conduit) thatmay be part of the farm groundingsystem.

It is desirable to place the energizeroutdoors and near the earth-returnrods to keep the return lead a short aspossible and to the reduce the possibil-ity of interaction of the fencer circuitwith the farm’s electrical circuit.(Figure 2)

How many earth-return rodsdo I need?

The optimum number of earth-return rods depends on the poweroutput of the energizer and the soilconditions. Manufacturers suggest from3 to 6 feet of earth-return rod for everyjoule of energizer output. A 10-joule

energizer would require from 30 feetof earth-return rod in wet, conductivesoil to 60 feet of earth-return rod indry or high resistance soils. Fourearth-returns rods at eight feet eachequals a total of 32 feet of earth-return rod. Eight earth-return rods of8 feet each equals a total of 64 feet ofearth-return rod.

How far apart should therods be placed?

For maximum effectiveness spaceearth-return rods at twice the rodlength. For example, eight-foot groundrods should be placed 16 feet apart.(Figure 3)

What material should beused for an earth-return rodsand wires?

The earth-return rods can beeither galvanized or copper-clad steelfrom 1/2 to 3/4 inch in diameter.Copper-clad rods are more resistant tocorrosion. Different types of claddingmetals should not be used in the sameearth-return system. The ground leadshould be # 8 copper wire or largerwith 600 volt insulation.

Building an Earth-Return System

How do soil conditionsaffect the performance of anelectric fence?

Dry or rocky soil has a higherresistance than heavy wet soils.These high resistance soils requiremore earth-return rods.

These additional earth-returnrods help to reduce the resistance ofthe energizer circuit and improve itseffectiveness. The soil resistancemay also be reduced by using anenhancement material around therods; e.g., GEM®, coke or bentoniteclay. Another way to solve theproblem of high resistance soils is touse a continuous ground fence.

How do I know if my earth-return system is working?

Specialized meters are availableto measure the strength of theelectrical pulse at locations alongthe fence. Check the fencer pulse atlocations near the energizer and farway from it. If the pulse strength isinadequate at locations far from theenergizer the earth-return systemneeds improvement.

Connecting an Energizer to a Fence

How do I get electricity fromthe energizer to the fence?

The ‘lead-out” wire that connectsthe energizer to the nearest energizedfence wire should be size 12-gauge orlarger.

If there is any possibility of thelead-out wire coming into contact withanything but the energized fence wire,high voltage insulation must be used.Never use standard electrical wire forthe lead-out. Standard insulation isnot rated to handle the high voltagepulses produced by an energizer. Mostcommon wire is designed to carry 120or 240-volt power and the insulation iscommonly rated for 600 volts. Ener-gizer voltage is much higher than the600 volt rating on most common wire.Use special wire with a minimuminsulation rating of 20,000 volts forthe lead-out from the energizer to theenergized fence wire.

If you are going to bury the lead-out wire, place it in non-corrosive,non-metallic electrical conduit toprevent physical damage to the wireand reduce the possibility of electricalleakage into the earth.

Do I need a cut-off switch?An easily accessible cut-off switch

is recommended. Most energizermanufacturers do not recommendcontinually unplugging the energizerto turn it off. A cut-off switch that iseasy to see from a distance (i.e.,whether it is on or off) will save timein maintaining the fence.

What is the best way toconnect a lead-out wire to theenergized fence wrie?

There are several different devicessold for connecting lead-out wires tofence wire. The most importantconsideration is to make sure theconnection is good and will not

corrode easily. The poor connectioncreated by twisting wires together willreduce the effectiveness of the fenceand increase the probability of connec-tion failure. It is a good idea to have aconnection that can be removed forcleaning; or, to be able to changewhich wires on a fence are energized.Bolted connections perform well.

How many energized fencewires do I need?

The number of ener-gized fence wires dependson the intended use of thefence. A single energizedwire usually works well forolder cattle and horses. Ifsmaller and/or youngeranimals need to be con-trolled, additional ener-gized wires may berequired. Cattle andhorses seldom need morethan three energizedwires. Sheep and goatsnever need more than five.

“The poor connectioncreated by twisting wirestogether will reduce theeffectiveness of the fence

and increase the probabilityof connection failure.”

7

What is the differencebetween a standard andcontinuous ground fence?

A single wire fence with standardgrounding is shown in Figure 4. Thisis the most common from of earth-return circuit used for electric fences.Only one energized wire is shown inthe figure but more energized wirescan be added if needed.

A two-wire continuous groundfence is shown in Figure 5. This typeof fence is suggested for dry, sandysoils or other conditions creating ahigh resistance in the earth-returnpart of the fencer circuit.

In a continuous ground fence, theanimal needs to touch both a hot wireand a return wire. When the animaltouches both wires electrical currentflows from the hot wire, through theanimal and back toward the energizeron the return wire. The earth-returnpart of the circuit is created by a pairof earth-return rods located near eachother to reduce the resistance of theearth-return path and maintain thevoltage of the fencer pulse. If ananimal touches only the energizedwire it will experience a lower inten-sity shock.

Are there any disadvantagesof a ‘continuous groundfence’?There are two main disadvantages tocontinuous ground fence:

If an animal touches only thereturn wire, it will not get shocked.If the bottom wire is the returnwire the animals will eventuallylearn that they can go under thewire without getting shocked.If the energized and return wirescome in contact with each other ashort will occur rendering thefence ineffective. The wires can beshorted by events such as a branchfalling on the fence.

8Connecting an Energizer to a Fence

Why should an electric fencesystem be protected againstlightning?

An electric fence is a large an-tenna for lightning. During a thunder-storm the fence wire and its earth-return circuit provides an easy routefor lightning to reach the earth —possibly through your energizer orother electrical equipment! It isimportant to protect fence energizersand all other sensitive electricalequipment on the farm from lightningstrikes.

What is a lightning arrestor?A lightning arrestor protects the

energizer from lightning strikes onthe fence wires. It is a simple devicethat is connected between the ener-gized wire of the fence and an earth-return rod or dedicated lightingprotection ground rod. Most lightningarrestors work like spark plugs withtwo metal electrodes near one anotherbut not touching. During normaloperation there is no electricalconnection from the fence wire to theground rod. If lightning strikes thefence wire the high voltage will causean arc, or jump the gap between thetwo metal electrodes allowing thelightning strike to discharge throughthe rod into the earth. The arcproduced by a lighting strike willusually destroy the arrestor and itmust be replaced.

What is the best type oflightning arrestor?

An arrestor that allows you to seewhether it has been hit by lightning isrecommended. These models aregenerally a bit more expensive butthey save time in determining if alightning strike has destroyed thearrestor.

What is a lightningbrake?

A lightning brake is a coil ofwire that develops an electro-magnetic field when electricityflows through it. This electro-magnetic field acts as a ‘brake’that provides a high resistancepath between the lightning andthe energizer in the event of a

lightning strike. This high resistanceprotects the energizer by forcing mostof the energy from the lighting to thelower resistance path through thearrestor and to the ground rod ratherthan thought the energizer.

Lightning Protection 9

What can be done to protectthe power supply side of theenergizer?

The energizer is a target forelectricity from a lightning strikeanywhere on the farm power supplyside of the circuit, because it isconnected to the excellent groundingnetwork provided by the earth-returnnetwork. The energizer can be pro-tected from lightning strikes on thefarm power side of the circuit byinstalling a surge suppressor at thereceptacle used to power the ener-gizer.

It is a good idea to protect all ofthe sensitive electrical equipment onthe farm with a surge protector.

Can lightning enter theenergizer from the earth-return system?

Lightning can destroy the ener-gizer due to improper installation ofthe earth-return system. Specifically, ifanything above ground is connected

Lightning Protection

to the earth-return system (e.g.,fences, silos or anything made ofsteel), a lightning strike to any ofthese structures has an easy path tothe energizer.

How many lightningarrestors should I install onmy fence?

Each lightning arrestor should beattached to an 8-foot ground. Thetotal length of lighting protectionground rods should be at least equalto — but preferably greater than — thetotal length of earth-return rods. Forexample, if you have a 10-jouleenergizer and 32 feet of earth-returnrods, you should install at least 4lightning arrestors around the perim-eter of the fence with an eight footrod at each.

Where should I install thelightning arrestors?

One lightning arrestor should beinstalled near to where the energizeris connected to the fence. The other

arrestors should be placed evenlyaround the perimeter of the fence inplaces that are easily accessible forinspection. Other recommendedlocations include near gates, at fencecorners and at the high point of hills—all places where lightning is mostlikely to strike.

Is it possible to be totallyprotected against lightningstrikes?

Proper installation of an electricalfence system, along with protectivemeasures on both sides of the ener-gizer, will greatly reduce the probabil-ity of severe damage from a lightningstrike. Unfortunately, it is not possibleto be completely protected. Highenergy lightning strikes can over-power even the best safety measures.

“It is important to protect fenceenergizers and all other sensitiveelectrical equipment on the farm

from lightning strikes.”

10

Cow Trainers

Cow trainers and crowd gatespresent several uniqueproblems. A cow trainer is

designed to train cows not to archtheir back while defecating or urinat-ing so that waste falls in the gutter.Cow trainers must be carefully ad-justed for each individual cow in orderto be effective. A great deal of stressand agitation will be produced if cowscannot easily avoid the trainer. Withmost cow trainer circuits, the barnfloor is part of the earth-return path.It is likely, therefore, that the trainerpulses will appear at all locations inthe barn whenever any cow touches atrainer bar. This makes it especiallyimportant that trainers be adjusted

properly so that cows contact thetrainers infrequently.

What size energizer shouldbe used?

Never exceed a 2500-volt ener-gizer for a cow trainer. Too muchpower can cause excessively nervousbehavior in animals. Furthermore,higher voltage increases the likelihoodof the energizer pulses traveling toundesired locations.

How should cow trainers beadjusted?

Adjust the trainer bars so they areapproximately 3 inches above thecow’s shoulders, or until they areeffective in training the cows to drop

their manure in the gutter. [Note: Thismay be as close as 1½ inches in somecases.] It is essential that the trainerbe fastened securely to eliminate thepossibility of the unit sliding downonto the cow’s back. It is also impor-tant to make sure cows get back intotheir own stall which has had thetrainer bar adjusted for them. If thiscannot be done then the bars must beadjusted every time cows return to thebarn.

What type of wire should beused?

Always use wire with 20,000 voltinsulation for the lead-out from theenergizer’s hot terminal to the trainerconnections. Do not connect the high

voltage output terminal toanything not associated withthe energizer.

11

Electric crowd gates aredesigned to train cows toenter a milking parlor. These

devices should be fitted with a bell orbuzzer so the cows know when it willbe moved. The potential for misuse ofthese devices is great. If an inattentiveor overly aggressive operator makes itimpossible for cows to avoid the crowdgate they will be frightened andagitated before being milked.

These devices work in a similarway to electric fence systems; however,extreme care must be taken in theirinstallation, because the high voltagepulses are flowing in and around abarn. Special attention must be paidso that these pulses do not appear onparlor stalls, waterlines, or otherconducting surfaces in the animalconfinement areas.

How can I improve thesafety of an electric crowdgate?

To improve the safety of electriccrowd gates, use an energized wirealternating with a return wiresimilar to a continuous groundfence as described earlier in thispublication. There are severalelectric fence supply companies thatmanufacture plastic/metal tapecombinations that have both hotand return wires woven into thesame material. Keeping the electri-cal flow in the wires rather thanthrough the floor reduces thepossibility of energizer pulsesoccurring in unintended locations.

Where should earth-returnsbe installed for cow trainersand crowd gates?

The recommended location andinstallation of the earth-return rodsfor a cow trainer and crowd gate isshown in Figures 8 and 9. Rememberthat each energizer (fencer, trainer,crowd gate must have its own dedi-cated earth-return system. DO NOTcombine the earth-return systemsfrom two different devices.

However, the same principlesdiscussed in the section on buildingearth-return systems for fences (size,type, number and placement of earth-return rods and connection to theenergizer) also apply for the earth-

return systems for your trainer andcrowd gate.

Why should cow trainers andcrowd gates be separatedfrom electrical and watersystems?

It is essential that both theenergized and return portion of theenergizer circuit for cow trainers andcrowd gates be electrically separatedfrom all grounded objects so that thehigh voltage energizer pulses do notoccur in undesired locations. Watersystems are the most likely place forearth-return currents to appear,because they are usually part of thegrounding system for the farmselectrical system.

Crowd Gates 12

Should I keep energizedwires away from other metalequipment?

Any metal object running parallelto an energized wire will pick up someof its voltage. This voltage can be keptto a minimal level if the metal objectis grounded. The National ElectricCode requires that any metal objectsthat could be come energized, such aswater pipes, milklines and stall workshould be grounded for safety reasons.The induced voltage can also beminimized by keeping the energizedwire as far from long metal objects aspossible and by keeping the length ofparallel runs to a minimum.

What is the best type ofinsulator?

There is not a “best” type ofinsulator. There are many new modelsand styles on the market. Bothporcelain and plastic insulators mayperform adequately as long as theyare kept clean. The most importantdifferences between insulators have todo with their strength and durability.

Do wooden posts needinsulators?

Yes. In wet or humid climateswooden posts should be fitted withinsulators. Wet and treated woodposts provide an electrical path toground and will reduce the effective-ness of an energizer.

Do fiberglass posts needinsulators?

Some types of fiberglass postsrequire insulators and some do not. If

Insulators, Posts & Safety Tips

the posts were manufactured specifi-cally for electric fencing, they gener-ally do not require insulators. Checkthe specifications of the post.

What type of post works bestfor electric fencing?

Any type of post will perform wellprovided the fence wire is insulatedfrom the earth. Each type has advan-tages and disadvantages. The mostimportant function of the fence post isto keep the wires where you wantthem.

Can insulators go bad?The effectiveness of an insulator

in a barn can re reduced if it becomescovered with dirt, white-wash or birddroppings. Bird droppings can be aproblem on fence insulators. Any formof debris, particularly when combinedwith moisture, will provide a leakagepath for the energizer pulse reducingthe effectiveness of the device and thepotential for fencer pulses to appearin undesired locations.

How often should I test thefencer system?

It is recommended that the fencerbe tested twice each year during thedriest period. Use a specially designeddigital electric fence voltmeter tocheck the voltage output at the powerunit and at various points along thefence. If the voltage is abnormally low,a short may exist. This may also be anindication that fencer pulses areoccurring in undesired locations.

How often should I inspectthe electric cow trainer andcrowd gate?

These systems should be in-spected every six months to ensuretheir proper operation.

Can electric fences causedeath or injury?

Any type of wire fence has thepotential of causing death or injuryto animals. The primary dangeroccurs if an animal becomes en-tangled in the fence. Smooth high-tensile wire is recommended forpermanently installed electric fencesfor three reasons. First, they arerelatively easy to install and maintain.Second, they can stand up to theabuse of animals and equipmentwithout breaking. And third, animalsare not as likely to become entangledin them. BARBED WIRE SHOULDNEVER BE USED on an electrifiedfence.

Can electrical transmissionlines cause problems with afence?

Voltage can be induced on anyconductive element, such as a fencewire, that is running parallel to a highvoltage transmission line. If a fence isinstalled next to a transmission lineand voltage can be detected evenwhen the energizer is turned off, itmay have to be moved or replacedwith a different type of fence. If youare receiving shocks from a fence thatis not energized, and the fence islocated near a transmission line, callyour utility and discuss this with afield representative.

13

Acknowledgements & References

AcknowledgementsThe Wisconsin Farm Electric Council would like to thank Mr. Thomas Cadwallader, Lincoln

County UW-Extension Office, for his contribution in the preparation of the text. We would alsolike to thank field experts from Wisconsin, Minnesota and Iowa who participated in thedevelopment of this publication.

ReferencesAmerican Society of Agricultural Engineers (1990). Test Procedure for Measuring the Output

Characteristics of an Electrical Fence Controller. ASAE Standard: ASAE S500. ASAE,2950 Niles Rd., St. Joseph, MI 49085-9659.

Cadwallader, T.K. (1996). Constructing an Earth Return System. Grazing Reference MaterialsManual. University of Wisconsin Extension and College of Agriculture and Life Sciences.UWEX, Extension Bldg, 432 N. Lake St., Madison 53706

Cadwallader, T.K. (1996). Keeping the Current Flowing on an Electric Fence. Grazing ReferenceMaterials Manual. University of Wisconsin Extension and College of Agriculture and LifeSciences. UWEX, Extension Bldg, 432 N. Lake St., Madison 53706

Cadwallader, T.K. (1992). Understanding the Basics of Electric Fence Energizers. GrazingReference Materials Manual. University of Wisconsin Extension and College of Agricultureand Life Sciences. UWEX, Extension Bldg, 432 N. Lake St., Madison 53706

Cadwallader, T.K. (1996). Protecting an Energizer from Lightning. Grazing Reference MaterialsManual. University of Wisconsin Extension and College of Agriculture and Life Sciences.UWEX, Extension Bldg, 432 N. Lake St., Madison 53706

Fick, R.J.; Surbrook, T.C.; Holycross, M.G.; and Althouse, J.R. (1998). Electric Fence SystemInfluence on Animal Contact Voltage. Written for presentation at the 1998 InternationalMeeting Sponsored by the American Society of Agricultural Engineers. ASAE, 2950 NilesRd., St. Joseph, MI 49085-9659.

Gustafson, R.J. and Winter, D.F. (1990). Use of Electric Current for Training and Control ofAnimals. American Society of Agricultural Engineers. Paper No. 90-3539. ASAE, 2950Niles Rd., St. Joseph, MI 49085-9659. Wisconsin Department of Agriculture, Trade andConsumer Protection.

Installation of Electric Fence Controllers, ASAE EP568, April 1997

Safe and Effective Electric Animal Controllers: Fencers, Cow Trainers & Crowd Gates. Preparedin cooperation with the Wisconsin Public Service Commission and University of WisconsinExtension. WDATCP, 2811 Agriculture Dr., Madison, WI 53704.

14

15Checklist for each Energizer

EnergizerSelect properly sized Energizer

See pages 4 and 5 for fencers or page 11 for cow trainers or crowd gates

Earth-Return SystemEarth-return Rods 8-foot Copper clad or galvanized

See page 6 to determine the number of rods needed for each energizerWire from energizer to the earth-return rods:

#8 stranded copper wire with Insulation rated for at least 600 voltsBolt-on-lug or “acorn” connectors to attach wire to earth-return rods (one for each rod).

Connect Energizer to energized wire, trainer or crowd gateHigh voltage lead-out wire from Energizer to fence, trainer or crowd gate

High voltage wire with insulation rated for at least 20,000 Volts long enough toconnect energizer to nearest energized wire.Bolt-on lug, screw terminal or other compression type connector to attach lead-out wireto the energized fence trainer, or crowd gate wire

Lightning ProtectionLighting Arrestors - one for each ground rodlighting protection ground rods - same number and size as earth-return rods Surge Arrestor

Cut-off switch

Split-Bolt type compression connector“Acorn” type Ground-rodClamp

Crimp-on type compressionconnector (requires specialcrimping tool)

Notes…

02-05

T

Mission Statement

his publication was developed by theMidwest Rural Energy Council.

The mission of the MREC is to initiate, develop, support, andcoordinate education, research, and communication

programs on significant and emerging rural energy issues forthe consumer, energy suppliers, and allied industries through

cooperative efforts of council members.

Related Publications from theMidwest Rural Energy CouncilFarming Safely and Efficiently with Electricity

Equipotential Planes for Stray Voltage Reduction

Planning Electrical Systems for Dairy Expansions

Power Quality and Computers on the Farm

Stray Voltage Detection, A Self-Help Guide

We invite you to visit our website at the following address: http://

www.mrec.org

Midwest Rural Energy Council