These switches regulate the lighting at certain specified positions of the room, for instance those at which work is carried out.
Localised switches produce noticeable energy savings and increase user satisfaction compared with the common situation where the lighting in the entire space is controlled with a single switch. Indeed, studies in open offices have shown wide variations in user preference for lighting, with some occupants switching their lighting on under almost all conditions and others doing so only on rare occasions. Localised switching provides more flexible control of the lighting of a worker’s space than a bank of switches mounted at the main entrance of a space.
Localised switching is important where only part of a large space requires the electric lighting to be on, either because the other parts are unoccupied or because daylight there is adequat. In general, the area controlled by a particular switch should have a similar daylight level in all parts. It should also be related to the occupancy pattern. For example, in an office where individual occupants may be absent it should cover the space of a single occupant or small working group; in a factory it could be related to a particular production line or process. As a guide, local switches should be no further away from the furthest luminaire than 8 m or 3 x room height if greater.
