What is the definition of a occupancy switch? An occupancy switch is a device that detects the presence of people in an area and can activate or deactivate lighting and other electrical equipment. This type of switch is often used in commercial spaces, such as offices, warehouses and stores, as well as in residential applications. It is typically connected to a lighting and control system that provides automatic lighting control in response to occupancy. The occupancy switch can also be used to control heating and cooling systems, fans and other equipment. Occupancy switches can be either manual or automatic. Manual switches require the user to physically activate the switch and to turn it off when the space is no longer occupied. Automatic switches have the capability to detect when people enter or leave the space and adjust the lighting and other devices accordingly. Occupancy switches are an efficient and cost-effective way of managing energy consumption in a space, as they can reduce energy costs by reducing the amount of time equipment is running when no one is present.