SMS Based Control of Electrical Appliances

Abstract

In today’s developed and technologically advanced world, automation is fast becoming a norm. From everyday items such as the doors to much advanced electrical equipment such as cars, washing machines etc. have all been automated for the ease of individuals. The project proposes a similar automation where switching operation of electrical appliances would be controlled based upon text messages. The project involves design and fabrication of a stand-alone device that is capable of switching various electrical appliances connected to it. It has been implemented in final product form and also supports some additional advanced features such as device feedback, scheduling, timed operations, critical data maintenance on power down, power save/idle mode, password set/reset, operation notifications and notification enable/disable option. It is password protected to avoid any un-authorized access. It also offers better safety measures against sparking since it utilizes solid state relays which do not have any mechanical parts as compared to electromechanical relays. GSM technology has been utilized since it has more outreach and is prevalent in Pakistan as compared to both GPRS and EDGE. The device has a current rating of 10 amps presently. The bottleneck in design are the wires utilized, as they can only conduct up to 10 amps but the solid state relays have a rating 40 amps, whereas the feedback circuitry can sustain up to 30 amps of current. Thus current rating of the device can be boosted up to as much as 30 amps if required. In current state, it can be used to control the operation of electrical appliances with power rating of 2200 W or less. This includes electrical appliances such as fans, lights, television, computers, battery chargers, electric iron, refrigerators etc. It can not only be utilized for ease or convenience but it is also particularly useful for medically unfit people who cannot move about.