Switchgear is a term used to describe a wide variety of switching devices that control, protect, and isolate electrical equipment in an electric power system. It is used to de-energize equipment to allow work to be done, protect equipment from electrical overload, and enhance system availability by allowing more than one source to feed a load. Switchgear is composed of electrical disconnect switches, fuses, or circuit breakers. The most common component found in switchgear is circuit breakers, which are designed to interrupt the flow of power during an electrical fault, effectively limiting damage to the system. Switchgear also provides isolation of circuits from power supplies. There are three different classes of switchgear systems: low-voltage, medium-voltage, and high-voltage. High-voltage switchgears are those that control 75KV of power or more. Switchgear is commonly found throughout electric utility transmission and distribution systems as well as in medium to large-sized commercial or industrial facilities.