Disconnect the power source to the electric fence charger. The charger is the main power box that the connects the ends of the fence and the ground line. Most fence chargers have a power cord that you simply unplug from the outlet. Some fence chargers use batteries, requiring you to remove the battery cables. Remove the wing nut securing the the positive cable first and then remove the negative cable.
Remove the fuse on the outside unit. The fuse may be hidden behind an access panel. If so, unscrew the access panel with a Phillips-head screwdriver and pull the fuse out of the charger
Remove the fence wires from the terminal inside the fence charger. Loosen terminal screws with a Phillips-head screwdriver if your charger uses screws to connect the ends of the electric fence wire. Turn wing nuts counterclockwise to remove the fence wires, if your charger has these type of terminal fasteners.