Design analysis of a micro controller based automatic switching system using passive infrared sensor

Abstract

Poor management and conservation of public power supply has constantly resulted into wastage of electricity there by limiting the industrialization process especially in third world countries. To reduce energy wastage in homes, institutions and public places, this paper presents the development of  an automatic switch using passive infrared sensor (PIR). Automatic switch is adevice that detects the human presence in a pre defined area and  can turn on the lights or any electrical appliances. Similarly, the device will automatically turn off the lights or any electrical appliance if nobody is present in  the area. Using the PIR sensor (for human detection), Light Dependent Resistor (LDR) (to detect night and day), and a micro controller programmed  using Micro-C, as witching circuit that detects humans in a pre defined area is investigated. In particular, an automatic switching system using passive  infrared sensors to prevent unwarranted wastage of electricity, and also to prevent electricity related hazards which could result from the use of  unmonitored electrical appliances is implemented. The research work guarantees less consumption of power, hence, lower utility bills. Also, it allows for more safety in homes, schools, and offices since heavy-duty and high-power equipment that could cause fire e.g. Air-conditioning systems, electric  cookers, boilers, electric irons etc, if left unattended to, can be turned off automatically.