The best way to isolate a problem on an electric fence system is to follow the steps below:
1. The most common problem is vegetation in direct contact with a charged wire. You should trim back and remove any growth of tree fronds, leaves, grass or climbing vines from contact with your electric fence. Make sure that charged wires are not attached to trees, in order to prevent shorting. Always use insulators.
2. To test the charger, disconnect it from the fence and read with a “high voltage” voltmeter designed for electric fences, to determine if you have full voltage output. The voltage should be the full rated volts on the voltmeter. Warning: A regular voltmeter will be destroyed if you try to measure the fence output voltage.
To double-check the charger you can make a jumper from a piece of insulated wire and short across the output terminals. You should be able to draw an arc about 1/10 inch (2.5mm) and will hear a sharp snap sound if the fence energizer is working properly.
3. With the charger connected to the fence, read the voltage on the built-in voltmeter. If the voltage is lower than the rated volts, then check the following:
a) There may be an accidental connection between charged and grounded wires on the fence. Make sure that all of the fence wires are isolated from each other, and that only similarly charged wires on multi-wire fences are connected together.
b) There may be an accidental connection between a charged wire and earth ground. Make sure that extra ground rods installed along the fence are only connected to the ground return wire, and not a charged wire. Make sure that the charged wire is not touching metal posts or metal objects sitting on the ground. Make sure that a charged wire does not go through water in a plumbing system or through a standing puddle of water.
c) The earth ground rod(s) may not be adequate or the earth around the ground rods may be too dry to conduct current properly. This condition results in excessive ground voltage and less on your fence. You may have to install additional ground rods in a location where the earth is moist all year round. It may also be necessary to add more ground rods and/or use a ground return wire on a multi-wire fence.
d) Check the voltage from the battery. The fence charger will not work correctly if the input voltage from the battery is not 12 volts.
4. There may be loose or corroded connections where the wires are spliced or connected to the high voltage source. Also make sure all the earth ground system connections and ground return connections are solid and not corroded. It is important to insure a solid and complete electrical path for proper operation.
5. If the charger output voltage is low or zero when the charger is disconnected from the fence, then replace or repair the high voltage charger/energizer.