Short Circuits, Circuit Overloads, and Overcurrent Protection

An electrician with more than four decades of experience, Alan Courtemanche joined Rockville, Maryland’s Standard Solar in 2015. He initially worked for Standard Solar as an electrical superintendent, but has since advanced to the position of senior quality assurance inspector. Alan Courtemanche manages several responsibilities in his position as an NABCEP-certified inspector, such as enforcing the National Electrical Code.

As the industry benchmark for safe electrical installations and designs, the National Electrical Code (NEC) provides the basis for most local codes found throughout the United States. The NEC provides electricians with information regarding a variety of electrical products and procedures, such as the basics of overcurrent protection.

The science of overcurrent protection has been developed with the goal of preventing electricity from flowing in an abnormal and potentially dangerous manner. In the absence or failure of overcurrent protection, a circuit can be at risk for a short circuit or overload.

A short circuit occurs when electricity flows through a pathway that is shorter than the intended route. As electricity flows beyond the parameters of the circuit, the circuit breaker automatically shuts off. Some of the most common factors involved in short circuit accidents include animals chewing through circuit wires and water damage. In some cases, the cause may be as simple as a loose connection.

Ground faults are a specific type of short circuit that occurs when an active wire touches a grounded portion of the device, or any component powered by the electrical circuit.

An overload, meanwhile, occurs when a circuit is subjected to more electricity than it has been designed to handle. When a residential circuit is overloaded, it will typically shut off, an important safety measure against house fires. In addition to a sudden power failure, signs of an overload include dimming lights and outlets and switches that are buzzing or warm to the touch.

A few of the devices commonly used to combat overcurrent damages and interruptions include fusible links, fuses, and circuit breakers. Home and business owners frequently experiencing short circuits, overloads, or ground faults should discuss improved overcurrent protection with a professional electrician.