The main disconnect is a device installed in most electrical systems within customer facilities. Today’s electrical codes require some type of disconnecting device such as a switch to simultaneously shut off all the circuits within the facility. For most homes and offices this is the main breaker in the breaker box, which is designed to shut off power to all the individual breakers. In some systems or older or larger facilities, main disconnects are used instead of main breakers. If a customer’s facility comprises multiple buildings, it may be desirable to have a main disconnect switch that can shut off power to all buildings rather than individual breakers for each building. The main disconnect is usually owned and installed by the customer.