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Instructions for Installing an Electric Fence to Control Beavers

A low four wire electric fence
Height: 3 feet



These pages provide the following: 

Parts List: 

Other Items Needed:

·         Gardening or work gloves

·         Knife

·         Wire cutters

·         Hammer

·         Trowel

·         Twist ties or nails

Installing the Fence: 

1.            Clear the path over which the fence will run.

2.            Set the steel U-posts a foot into the ground at the following locations:
- fence corners
- ends (where the fence runs into a building, wall, or other fence)
- both sides of any gate opening

3.            Attach the insulators to the fiberglass posts:
Attach four clip on insulators to the fiberglass posts at your desired wire heights.  We suggest spacing the wires at 9 inch intervals.    Keep in mind that the posts will be driven 1 foot into the ground.

Attach the insulators when the temperature is above 40º F to prevent cracking the insulators. If setup must occur during freezing, you may bring the insulators over to each post in a bowl of warm water.

4.            Insert the fiberglass posts:
Space your fiberglass posts out so that there is no more than 10 feet between any two fence posts.  Insert them 1 foot into the ground.

If you need to pound a fiberglass post in with a hammer, put a small board between the hammer and the top of the post to avoid marring the post top.

5.            Attach the U-Post insulators:
Attach four U-post gate insulators to each gate post at all four wire heights. Use the cotter pins provided with the insulators.

6.            Attach the corner knob insulators to the U-posts at the corners:
Cut off a foot-long length of wire and run it through one of the corner insulator’s  channels, and twist the wire on. Then put the wire through the holes in U-Post and twist the wire around itself on the other side to secure it. Repeat this action on each of your corner posts at each height on the post where you want a fence wire.

The insulator goes on the inside of the corner. The actual active fence wire will later run through the second channel (the one not being used to attach to the U-Post) to make a corner.

Corner knob attachment can be confusing.  Please watch this
video playlist for a demonstration
Youtube channel:  Electric Fence Install – McGregor Fence Company
How to attach a corner knob to a U-Post and then string it with wire

7.            Begin stringing your fence wire:
Start at the right side of a gate post by winding the wire around the top insulator.
If it is metal wire, twist the end of the wire around the outgoing wire tightly several times to fix it firmly to the insulator.
If it is polywire, secure the end of the wire to the outgoing run with a split-bolt clamp, placing the clamp close to the insulator.

Proceed to run the wire (metal or poly) all around the fence, hanging it from the appropriate clip-on fiberglass post insulator on each post. Pull the wire reasonably tight manually as you go, making sure it is taut enough to maintain the proper height.

8.            Run wire through the corner insulators:
When you reach a corner, detach the appropriate corner knob from its post by untwisting the ends of the attachment wire. Then detach the attachment wire from the corner knob by untwisting the middle portion of the attachment wire a turn or two. Next, insert your fence wire (whether metal wire or polywire) into the inner channel on the corner knob, replace the corner knob in the loop of attachment wire, twist the middle part of the attachment wire around a couple of times to secure the corner knob, and reattach the wire to its former position on the post by twisting the attachment wire’s two ends together. Repeat this each time you come to a corner.

9.            String wire over gates:
When you reach the next gate, run the metal wire or polywire around the insulator several times to secure it without touching the insulator’s metal base. DO NOT cut the wire at this point. Instead, figure out how much wire is needed to span the gate opening and cut the wire at that point.

Thread the end of the wire through the hole at the back of a gate handle, arranging things so that the gate handle can hook onto the non-metal part of the gate insulator on the other side.
If you are using metal wire, twist the wire several times around itself at the back of the gate handle to secure the wire to the gate handle.
If you are using polywire, connect the two polywires at the back of the gate handle with a split-bolt clamp to secure the polywire to the gate handle.
Remove any excess wire at the back of the gate handle with a wire cutters.

10.       Continue to string the fence wire:
begin stringing fence wire at the gate insulator at the far side of the gate (the side where the gate handle hooks in). Continue in this manner until you reach the place on the fence where you started and terminate the wire at that point.

11.       Tighten saggy wires:
If the fence wire is running a little lower than desired at any point, tighten and raise it:
If you are using metal wire: taking an extra turn or two around a nearby fiberglass post (fiberglass is an insulator) or by twisting one of the wire’s clip-on insulators around the post a few times.
If you are using polywire: apply a polywire tensioner at this point.

Make sure that your fence wire does not come close to the metal base of any U-post insulator at any point.  Touching a U-Post will ground out the fence.

12.       String the remaining wires:
Repeat steps 7 through 11 in order to hang each of the three other runs of metal wire or polywire on your fence.

13.       Post the warning signs on or near the fence:
Give special attention to places where people are likely to be surprised by the fence.

14.       Install the ground rod:
The ground rod is best placed in a location that:
- has soil which is generally moist during the seasons when the fence will be working
- is close to the fence
- is reasonably close to the electric fence charger/energizer

This spot should also be at least 50 feet away from the grounding system associated with your home’s electric service.

15.       Hammer the ground rod (thread end up if you are installing the 2-footer) into the ground until only about 4 inches protrude.
If you are installing the 2-footer, place a board between the hammer and the top of the rod to avoid damaging the threads.
If you are installing the 6-footer, after the rod is in the ground slip the clamp over the top of it, undoing the clamp’s tightening screws a bit if necessary.

16.       Connecting the fence sections: (if using 2 or more gates, other interruptions):
Use insulated wire and split-bolt clamps to connect together the different sections of your fence.

To connect two sections of your fence across a gate opening or other interruption, cut a length of insulated wire 14 feet wider than your gate opening. Now take the insulated wire across the gate opening, burying it a few inches underground to keep it away from feet and lawnmowers. Bring the hookup wire up on the other side of the gate and attach it to the fence wire with a split-bolt clamp.

If vehicles will be coming through the gate it’s a good idea to put the hookup wire through a pipe to protect the insulation against cracking; also put some holes in the bottom of the pipe to ensure drainage.

DO NOT replace the hookup wire with regular insulated wire designed to carry house current, because the charger’s output, though harmless, has too high a voltage to be contained by house current wire, and so this substitution will prevent your fence from working.

17.       Spreading the charge among the four wires:
Ensure that all four wires are activated on each of the fence sections.  For each independent section of fence, connect the four electric fence wires to one another using small pieces of wire and split bolt clamps.

Charger/Energizer Installation and Trouble-shooting:

1.            Remove the fence charger/energizer from its package:
upon opening, read the installation instructions; including the safety provisions.

Never by-pass the charger, and never use an extension cord carrying house current outdoors in connection with this kit–because house current is dangerous and can create life-threatening situations.

Note that charger instructions are commonly written for cattle fence lines extending many miles in dry conditions. They often recommend installing multiple or 8-foot ground rods.  Unless your fence is in the desert or tundra, you don’t need so much grounding.

2.            Place your charger/energizer:

a.      If your charger is AC-powered, plug it into an AC outlet near the fence, arranging things so that you have enough insulated hookup wire to reach from the charger to the fence.

If your charger is being placed outdoors:
Prolong the charger’s life by providing some protection from the weather (rain and snow).  This can be done with wooden housing or with something as simple as the bottom of a 1 gallon plastic milk bottle, with a small vent cut in it.

If the charger is being placed indoors
Provide a small hole through a wall or woodwork that is large enough to admit the insulated hookup wire.

Do not pass the insulated hookup wire through a door or window opening, as this is likely to cause bending or other stress that could break the insulation.

b.      If your charger is battery-powered, get either D-cell batteries or a deep cycle battery of the appropriate voltage; these batteries (in contrast to car batteries) can be drawn down fully before being recharged. Locate the charger near the fence and connect it to your battery.

Prolong the charger’s life by providing some protection from the weather (rain and snow).  This can be done with wooden housing or with something as simple as the bottom of a 1 gallon plastic milk bottle, with a small vent cut in it.

c.       If your charger is solar-powered, orient it so that its solar panel catches maximum sun and place the charger near the fence.  Allow it some time to charge before testing it.

3.            Test the charger/energizer:
Plug in or turn on the charger/energizer; many have lights, meters, or clicking noises when activated.  Use your fence tester to touch both the positive and negative terminals simultaneously, and the tester should activate.  If it does not activate, you may have a problem with your battery/outlet/charger.  Run control tests to see if you have a defective battery/outlet.  If still unresponsive, the problem is likely with the charger, and you should call the charger’s maker to activate its warrantee.

4.            Connect the positive (+) terminal to the fence wire:
Unplug or turn off the charger. If you are using insulated hookup wire, strip 2 inches of insulation from it. Attach the wire to your charger’s POSITIVE (+) terminal. Run that wire out to the fence. Attach the other end of the connection wire to the fence wire with a split-bolt clamp.

If you are using insulated wire, put it an inch or so underground to keep it safe from feet and lawnmowers. Or else, if heavy traffic passes over the hookup wire at any point, put the wire through a well-drained underground pipe to protect it.

5.            Connect the negative (-) terminal to the ground rod:
Take a connection wire (either bare or insulated) that is long enough to reach from the top of the ground rod to the NEGATIVE (-) terminal on your electric fence charger.

If you have our two-foot ground rod
, thread the two nuts onto the ground rod. Open a space between the two nuts, loop the wire around the ground rod in this space, and tighten the nuts so that the wire cannot move.

If you have a 6-foot rod, tighten the clamp on the top of the rod with the two screws and unscrew the top screw until the hole below it is fully open. Slip the wire into the attachment hole and then tighten the top screw until the wire cannot move.

Then attach the other end of the connection wire to the electric fence charger’s NEGATIVE (-) terminal

Make sure that NOTHING attached to the charger’s positive (+) terminal–including the charged fence wire–has been connected directly or indirectly to the charger’s negative terminal. The positively charged system (positive terminal, hookup wire, polywire) must be kept entirely separate from the negative system (negative terminal, ground wire, ground rod, moisture in the ground). That’s because the beaver gets a shock when it provides a bridge between the two systems. If the systems are already hitched together, or if weeds leaning on the fence provide a better bridge between the two systems than the animal does, then the beaver will not get a shock.

6.            Test your fence:
Take your fence tester and check the fence wire at various points along the fence line.  Do this by inserting the tester’s needle (at the end of the cord) into moist ground and then touching the metal tip at the top of the tester to the charged wire. The tester should register a voltage similar to that advertized on your charger/energizer. If it doesn’t, even though the charger’s light is flashing, check all the connections on the fence to ensure that a good flow of energy is being maintained across all the connections. Once the tester is registering the desired voltage along the whole fence line, your fence is operating in a manner suited to repelling beavers.

Maintenance Tips:

The soil just outside the charged wire should be damp enough so that any animal touching the wire will be grounded. Wetting the fence line area during periods when the soil seems dry should help to accomplish this (remember to first turn off the charger to avoid a shock).

Be aware that animal impacts, falling branches, or plants leaning on the charged wire can neutralize your system. Therefore, inspect periodically for downed posts or lines and for encroaching vines, grasses, or other plants in order to minimize fence drain.

Finally, please note the following seasonal limitations of your system:
An AC-powered charger can operate through the winter, but very low temperatures can freeze the ground moisture hard enough to neutralize the system.
A battery-powered or solar-powered charger will be less effective in cold winter seasons, partly because of reduced sunlight and partly because chemical storage batteries tend to operate at less than full efficiency in cold weather.