Most electrical fence problems are caused by improper grounding. An electrical fence is an electrical circuit. Electric current flows from the charger over the fence, through the animal, through the ground to the grounding system, and back to the charger. If the grounding system is insufficient, the electric current will be reduced and the animal will receive less shock. Again, errors occur when electric current flows from the fence to the ground. It is often caused by grass, weeds, or hanging branches that touch the electric fence. Defective insulators can cause malfunction if the wire of the electrical fence reaches the fence post.