All About Energizers

Gallagher makes a number of different lines of fence charger products and within each you'll have multiple choices. What makes each charger different? Why do you need one over another? What joule rating do you need?

What Types of Charger Are Available?

AC, or 110V, fence chargers are simply powered directly by a connection to your electrical grid. Maybe you put your charger on your barn wall and plug it in there. Maybe you run an extention cable out to an energizer housing closer to your fence line. However you do it, your AC chargers have to plug in to the wall at some point making them very convenient and easy to use in most cases, but downright impossible when you have to power a fence line in some remote location. See Our AC Fence Chargers

ac fence chargers

DC, or battery-run fence chargers are, perhaps, even simpler to use than AC chargers. Instead of running a line directly to your wall outlet, a battery fence charger draws its power from an internal (or external depending on the model) power source. Typically, most Gallagher fence chargers are optimized to run on a 12V deep cycle battery (a car battery). This makes battery chargers very easy to use in remote locations, but also requires that the batteries be recharged every now and again to keep the fence up and running. You can minimize electric fence down time by keeping multiple 12V batteries and swapping them out on the charger when time comes for a recharge. See Our DC Fence Chargers

dc fence chargers

Solar fence chargers are pretty self-explanatory. Similar to DC chargers, a solar charger draws its energy from a connected power source (a battery). The difference is that a connected solar panel can then recharge the connected battery keeping it functional non-stop without the need for swapping batteries. This really makes solar solutions ideal for any temporary or rotational fencing implementation. See Our Solar Fence Chargers

solar fence chargers

Keep in mind that many chargers (even many Gallagher chargers) can be used interchangeably with different power sources. for example the "B" series of portable chargers (the B100, B200, and B300) can all be used with just a battery or a full solar setup. Similarly, most of the battery chargers can be converted to AC power with a simple adaptor available for fairly cheap.


What Do All The Numbers Mean?

Once you know what type of charger you need you can start to drill down to what size and power of charger you'll need.

As you look through our fence chargers online, you'll notice we make comparisons in power in Joules, Miles, and Acres. It is important that the numbers that are provided are under assumed "ideal" conditions (enough moisture in the ground, set up correctly, no weeds along the fence line, well insulated, and so on). I'll get into determining how these conditions affect your charger purchase a little further down.

Here's a bit about what each number means:

  • Joules - A measure of energy that essentially tells you the relative power of each energizer. For comparison with other brands, we provide both the "stored" and "output" joules for each product. Remember that the best use of this number is to look at two chargers and determine which one is more powerful. You won't likely ever get the recommendation to buy a specific joule level of charger. that is where measures of distance come into play. NOTE: Do not confuse joules and volts. All Gallagher products are around 7,000 volts at the charger. You won't likely need more than that for any animal control.
  • Miles - All our chargers come with a "miles" rating to help you decide which charger will be ideal for your length of fence. The longer your fence line, the bigger charger you will need to maintain 7,000 volts along the entire length. If you have 3 miles of fence line with 4 lines of poly wire you actually have 12 miles of fencing material to be powered. To make things simpler for you each of our charger products is rated at a "multi-wire" distance (3 wires) and a "single-wire" distance.
  • Acres - We don't suggest you make buying decisions off of acres because the distance of fencing surrounding a single acre can vary by as much as 60% depending on how you set up the perimeter. However, in making quick estimates and comparing with other manufacturers, the approximate acreage can be useful.

No Fence Situation is Perfect

The reality is that no fence is perfect. There will never be a perfect transfer of electricity from ground rods to through the ground. Its also very near impossible to set up every fence 100% perfectly.


Here are some of the environmental factors that may change which charger you ought to buy:

  • Poorly conductive soil - Dry soil tends to be a poor conductor of electricity. That means that your charger has to work harder to push energy through the ground to shock any animal coming in contact with the fence. This effect can be minimized by using a ground wire (usually an extra center wire run along the fence but connected to the ground terminal instead of the positive terminal). However, if you think you may have issues with grounding efficiency, you may want to consider a slightly stronger charger. See all our grounding products here
  • Undergrowth and weeds along the fence line - A second very common problem in electric fencing is weeds and undergrowth growing up into contact with the live wires at the bottom of your fence. This can cause some drain to your charger and over a distance can significantly reduce the effectiveness of your electric fence. Of course the correction is to keep you fence line clean of debris, weeds, etc. but you are very busy and there are times when you simply won't have time to care for it daily. If you think this could be an issue, make sure you buy a charger that is slightly stronger than the distance rating you require.
  • The number of lines in your fence - As mentioned before all our products come rated with a single and multiple wire distance rating. As you add more wires you are essentially extending the distance that energy needs to be pushed along your fence line. Without getting into the hairy math of it all, if you keep track of the total distance of fencing material you will be powering, that will be a safe estimate in most cases of the distance rating you are looking for (single-wire in this case). So, for example, if you have 1/2 mile of 6-wire fence, you would need to power 3 miles of fence material (6 lines * 1/2 mile = 3 miles)
  • Animal type - One last thing to consider is the type of animal you are trying to contain (or repel). The amount of charge required to let a bear know that it should leave will be far different than that of a small rabbit. The bigger the animal in question the higher up the spectrum you would need to go. Most of our chargers are also rated for what types of animals they can control.