Electric Fencing


Basics of electric fencing

Planning a fence

As with many things, proper planning and preparation will prevent issues and make things go a whole lot smoother.

  1. Consider leaving room on the outer perimeter of your fence so that you can cut the grass/weeds.
  2. Walk the planned fence line and get a good feel of the terrain. Keep an eye out for obstacles and areas that may flood.
  3. Adjust your fence line to deal with the terrain. You may want to make your fence higher where there is a possibility of flooding. A wire set at 6" will short your fence out if it is sitting in 8" of water.
  4. Do not use trees for fence posts. Trees grow.
  5. Think about how you will access the fields - both on foot and with equipment. Plan out appropriate gates.
  6. After you think everything is planned out, walk the fence line again with your plan.
  7. After you have put your posts in place - only run your lowest wire and tighten it. You can now walk the fenceline and see where you will need to adjust things.
  8. You will need a fence tester at some point, so might as well buy one when you get your fence.
  9. Also get at least one fence alarm and put it in a place where you can see it easily (and often).

Building a fence

This is the basic layout of our fence:
Our Fence layout Wires 1,3,4,6 and 8 are connected to the positive side of the fence charger.

Wires 2,5 and 7 are connected to the ground side.

The ground side of the charger is also connected directly to two grounding rods, as per its instructions.

So far, this has worked very well in containing our goats - except when we get more than 6" of snow (rare) or when the lower parts of our field floods.

The alternation (+/-) for the higher wires is to make sure that a goat will get a jolt even if it jumps.

Unless you have a very choice piece of property, you will probably have to deal with variations in slope.
Dealing with a hill When dealing with a hill, your posts must be at 90 degrees to the slope of the hill - NOT 90 degrees to "level".

Other than that, you can treat them just like if they were on flat ground in terms of spacing, etc.

Dealing with Dips / Rises presents a bit of a challenge.
What a dip does to the fencing A dip between fence posts will create a gap that animals can use to get in or out.

Our solution was to use one or more "T" posts to close the gap.

When doing this, make sure that your lowest wire doesn't come too close to the ground
If it does, use another "T" post to get the proper spacing.

What a rise does to the fencing A rise between fence posts will bring the ground closer/in-contact to the lowest wire.

Our solution here was to use one or more "T" posts to keep the wire at the proper distance.

When doing this, look out for creating too much space at the 'edges' of the rise.
You may need to use more "T" posts to keep gaps from forming.

Parts of the fence

This is a (cheaper) plastic insulator used to keep the wire (far) away from the post.
This one is in the feedlot, where there is an actual wire mesh fence stretched between the posts.
The (electric) wire is there to keep the goats from pushing on the fence.
This is a (cheaper) plastic insulator that is slightly shorter than the long one above.
This one is also in the feedlot, but higher up on the posts - where the physical fence is more 'flat'.
The (electric) wire is there to keep the goats from pushing on the fence.
This is a (cheaper) plastic insulator that I used on the posts out in the field.
It handles the up and down force of the wire well. It does not do well when there is any horizontal force (such as when a fence changes direction slightly).
The wire will 'eat' through it fairly quickly even with only a small amount of pressure in that direction.
This is a slightly more expensive plastic insulator. (Ceramic ones are more expensive still, haven't used any of those). These do handle some horizontal pressure, but don't use them for corners or major bends.
These devices are used to maintain tension on the fence. There is a sort of lever that goes with them, and you use it to crank these around.
There is a spring, ratchet, and some teeth that work together to keep the spool from going backwards after you crank it with the lever.
The electric wire does stretch over time, so you may need to retighten things now and again.
The tension can be loosened by cranking slightly then holding the spring so the ratchet doesn't engage the teeth. Do this if your fence breaks and you need to repair wires..
They require another (insulated) wire to hold them to the post.
This sort of insulator is for corners, but I also use them for starting (ending) a run of wire.
The fence wire goes around the outside of the insulator, and another (insulated) wire goes through a hole in the middle.
The second wire is then looped around the post and twisted.
This is one of my 'endposts'. As you can see, I alternate tensioners and corner insulators to keep things from 'rubbing' and to give me a bit more room to work (the ratchet) in.
Here we have a corner post. I guess this is the 'real' use for the corner insulators - they act like wheels for the fence wire to allow it to move freely.
This post is at a 'bend' in the fenceline. I used the less expensive plastic insulators, but even so one broke - so I replaced it with a corner insulator.
I'll replace each insulator as it fails with one of the corner ones. (lesson learned).
Here you see a dip in the ground that I dealt with by using a less expensive post made from what looks to be rebar. It isn't as tall as a "T" post but it does reach the first 4 wires of the fence. At some point I will add an additional wire 'branched' off the lowest fence wire just to cover the gap here.

Trouble shooting

Ok, so your fence alarm is going off. Or, you chose to use the animals as a fence alarm and now they are wandering about.
First, make sure the animals aren't going anywhere. Food is a good distraction.
Now its time for: troubleshooting your fence.
Activity Actions Description
Walk your fenceline
  • Broken wires
  • Wires touching each other
  • Wires laying on the ground
  • Wires touching the (T) post
  • Check each insulator
    to make sure it has its wire.
  • Downed/broken posts
  • Something shorting out a wire
You are checking that the fence is physically intact.
Things happen to fences: trees fall on them, animals run into them, over time wires will stretch and insulators will break.

I have found that the fence wire has a tendency to "eat" through plastic insulators over time (the wire is under tension, after all).
Test your charger
  1. Unplug your charger
  2. Unhook the "+" and ground wires
  3. Plug it back in
  4. Measure the voltage across its output terminals with your fence tester
  5. Compare your measured voltage to the expected voltage
You are checking that the fence charger itself is working (disconnected from the fence).
They are electric devices, and are not expected to work forever.

The voltage you measured should match (or at least be close) to what the manual for the charger says it should be. If it is not, your fence charger is not working correctly. If you read zero, your charger is not working at all.
Measure voltages on the fence.
  1. Unplug your charger
  2. Hook the "+" and ground wires back up.
  3. Plug it back in
  4. Walk your fence line, measuring voltage:
    1. Between each wire and the ground
    2. Between each wire and all the others
  • There should be little or no voltage difference between 'like' lines (+/+ or -/-).
    If there is, find which line is most different and figure out why.
    • Lower voltages on the + line indicates that the line is (partially) shorted.
    • No voltage on the + line indicates that the line isn't tied into the others.
    • A voltage difference on the ground line indicates that it isn't tied into the others.
  • There should be little or no voltage reading between a ground line and the soil. If there is, then you need extra grounding.
  • The voltage between the soil and each + line should be about the same. If it is different, choose the lowest voltage line and trace it.
Test wire by wire.
  1. Unplug your charger
  2. Disconnect any and all 'tie' wires on your fence.
  3. Disconnect the 'ground' wire from your charger to the fence.
  4. Disconnect any additional grounding rods from the fence.
  5. Hook the '+' wire from the charger up to only one wire on your fence.
  6. Walk your fence line, measuring voltage:
    1. Between each wire and the ground
    2. Between each wire and all the others
  7. Repeat this for each wire on the fence.
  8. If your fence is in sections, start connecting sections back together - keep each wire 'loop' seperate from the others in the fence.
  • The one wire that you have hooked up should be (almost) at the maximum voltage that the charger puts out.
  • There will most likely be a reading of some low voltage on the other lines - this is due to inductance. If the voltage is high, then the lines are still tied together somehow.
    Check to see if you didn't miss a tie line, or if the wires are resting on a T post or something.
  • The object is to test each wire (loop) by itself.