Lightning and Electric Fences: How to Protect Your Livestock and Property

Lightning and Electric Fences: How to Protect Your Livestock and Property

Lightning is an unavoidable threat to livestock, farms and ranches. Since most farm operations are located in areas where there’s ample pasture land and plenty of open space, farm buildings and fences can often attract lightning during stormy weather.

Since this electricity follows the path of least resistance from the sky to the ground, it is often drawn toward objects that can serve as conductors. These objects include buildings, fences, trees, people and even the livestock themselves.

Protecting your electric fence from lightning strikes should be a top priority for ranchers, since a hit can destroy valuable electronics, kill livestock and destroy other property.

To best protect your electric fence, you should follow all of these steps:

  • Install a lightning arrester between the fence and the controller. Install one on every corner of the fence if possible. Keep these devices at least 50 feet from the energizer.
  • Add a Storm Guard to your 1 joule or higher charger to absorb any lightning that is able to move past the other devices. (Storm guard is included with all Zareba 100- and 200-mile chargers.)
  • Disconnect the energizer prior to a major storm, if possible.

By adding these devices, your fence charger has a better chance of surviving the stormy weather as they divert the energy away and into the ground.

What Does Lightning Do to an Electric Fence?

Lightning will always seek out the path of least resistance on its way to the ground. As such, fences with hundreds or thousands of feet of metal wiring in them make excellent conduits for the electricity blasted out of the sky in the form of a lightning bolt.

In fact, lightning rarely strikes a fence. Instead the lightning induces voltage on the fence line, and can happen even when lightning strikes several miles away from the fence. This type of energy induction can reach your fence as often four times a year.

As the energy from induced lightning travels along the fence, it seeks out a path that will deliver it into the ground while expending the least amount of energy. In the case of an electric fence, that path will be through its ground rod system, which is on the “opposite side” of the fence charger. That means if induced lightning hits an electric fence, it must travel through the charger to get to the ground rods. This route can total the fence charger in the process.

The other possible route for induced lightning to reach your fence charger is through a utility line. With that kind of strike, the electrical energy will travel through the utility line to the outlet and into the device itself. This surge of energy can also destroy the charger.

Direct lightning strikes on your fence will likely cause a failure to your fence charger no matter what precautions you make.

Physical damage to the rest of the fence is very rare. That being said damage can occur if the energy arcs unexpectedly from the fence to another object. Likewise, the energy from a lightning bolt can be strong enough to vaporize metal. That sort of surge can spell trouble for nearly any component of an electric fence.

Trees are frequently struck by lightning and are extremely dangerous for people and animals to stand under during a storm.

Trees are frequently struck by lightning and are extremely dangerous for people and animals to stand under during a storm.

Lightning Safety for Livestock

Livestock left in a pasture during an electrical storm are usually safe, but a particularly intense storm can decimate a herd. The biggest problem is that cattle tend to congregate under trees to keep out of the rain. Since lightning often seeks out and strikes the tallest structure it can find, cattle lingering under a tree canopy can be electrocuted by the ground current when lightning hits those trees.

Another problem with trees: Water soaking in roots and the sap coursing through a tree makes it an especially good conductor.

These factors combine to make the space under trees dangerous during lightning storms. Further, the ground near a tree is just about as dangerous – the current can electrocute anything standing in the wet grass nearby.

To protect your animals from lightning:

  • Move livestock inside a grounded building to protect them from direct strikes.
  • Only allow trees to grow in rows on your pasture, rather than in groups. This spreads out the chance for strikes, and theoretically limits the number of livestock injured.
  • Also note that certain trees with large root systems tend to be hit more often than those that don’t.
  • Place metal feeding troughs in low-lying areas, rather than on the top of the hill.
  • Further, you should make sure your herd is insured for lightning strikes.

A Bad Storm is Coming Right Now — What Should I Do?

Assuming the lightning storm isn’t directly overhead, you should first move to protect your livestock. Once you secure them appropriately, you can work to save your fence charger. Your best bet is to turn off the fence, disconnect the charger and remove it for the length of the storm.

Once the storm has passed, reconnect your charger and test your fence. After that, check to see if any debris fell on the fence or other damage occurred. Once you’re satisfied your fence is operating, allow your livestock to return to their paddocks.

There are a number of products to protect your electric fence from being damaged by lightning strikes. Investing in them can save your fence and keep your animals from wandering after a storm.

There are a number of products to protect your electric fence from being damaged by lightning strikes. Investing in them can save your fence and keep your animals from wandering after a storm.

Lightning Arresters and Other Lightning Protection

The primary concern for your fence during a lightning storm is your fence charger. Since it’s an electrical device, a sudden energy surge brought on by the storm can destroy it.

To protect your fence charger from lightning strikes you must prepare in advance by installing equipment that isolates your charger and discharges or absorbs lightning. These can include lightning arrestors, lightning diverters and surge protectors.

It is best to use a combination of these devices for maximum electric fence lightning protection.

LIGHTNING PROTECTION PRODUCTS
PRODUCT Lightning Arrester Storm Guard
SEPARATE GROUND ROD NEEDED? Y N
REPLACE AFTER STRIKE? Possibly Y
INSTALLATION TIME Hour (including adding ground rods) Minutes
PROTECTIVE FUNCTION Transfers lightning energy into the ground. Use in conjunction with Storm Guard. Attaches to fence at ground posts to absorb energy from lightning strike. Last point of contact. Protects charger.

Lightning Warranty

Zareba® offers full lightning damage coverage on all chargers under the two- and three-year limited warranties. Make sure to register your charger online to extend your warranty.

Lightning on the Farm

Is your farm or ranch susceptible to “bolts from the blue”? Tell us about the challenges you are facing in the comments below. We would also love to hear about your storm stories, which you can tell us about the next time you visit Zareba® on Facebook. Got questions on the operation or installation of our lightning protection products, send them to our online customer service center or call 855-5-ZAREBA.

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