Intelligent power saving system using PIR sensors

The main objective of this paper is to save power in IT work spots, using a PIR sensor capable of detecting only human beings. It deals with the concept of office automation which will be very much helpful to save power in the time of power crisis. A PIR sensor is fixed to each and every computer in the work spot. The PIR sensor fixed in the computer will sense its user for every 15 seconds as pre programmed in the controller which is fixed to the sensor. In the case of absence of user, the monitor is programmed to turn off. All the PIR sensor are centralized by a PIC controller (PIC 18F4520) in the department. This is capable of interfacing multiple electronic devices. It interfaces the PIR sensors with the relays. If a whole row or continuous 4 system is seemed to have no user then PIC controller is programmed in such a way to switch off the respective lights and fans (or AC shutters) by a interface between switchboard of light and fan control and PIR sensor. A DC relay is used for the turn ON and turn OFF purposes of electrical appliances according to the output obtained from the PIC controller circuit. A relay driver circuit is used to drive the relay according to the output pulses from the PIC controller.