pdf dtmf based load control system

[sheetal]

The project works on the concept of DTMF (dual tone multi frequency) tone command so received from any phone to remotely switch any electrical load such as agricultural pump, domestic and industrial loads etc. In industries, the loads are spread over a large area and thus, operating these loads is a very tiresome and difficult task.

In agricultural fields also, pumps and other loads are connected over a large area and hence it is difficult for the farmer to operate all the loads and similarly for house hold loads. Keeping these problems in mind, the proposed system has been designed which uses DTMF technology to control the loads remotely.

A cell phone is interfaced to a DTMF decoder in the system from its audio output socket for receiving tone commands. The receiving cell phone codes are converted into digital commands by using a DTMF Decoder which will identify the frequency of the key and convert that frequency to its equivalent digital code which is then fed to a microcontroller (8051 family).

As per the commands sent from the sender s mobile, the microcontroller will send signals through a buffer to actuate the respective loads by turning the relays ON/OFF. These relays are actuated by a relay driver IC interfaced to the microcontroller.

Further this project can be enhanced by using a GSM modem, where the loads can be controlled by sending an SMS. This will eliminate the need of answering the call for the system to work.

[greatjitz]

Project DTMF (dual tone multi frequency) tone ordering concept so any phone works on remotely obtained from such agricultural pumps, domestic and industrial weight etc industries to switch any electrical load, loads are spread over a large area and thus, these weights to handle a very tedious and difficult task.

Also in the agriculture sector, pumps and other loads are connected over a large area and therefore it is difficult for the farmer House work and so all the weight to. Keeping these issues in mind, the proposed system which loads to control DTMF technology is designed.

A cell phone voice commands to get your audio output socket is a DTMF decoder system interfaced with. Get cell phone code to identify an instance of that key DTMF decoder and digital code which is equivalent to a microcontroller (8051 family) is fed to that frequency will change are converted to digital by using commands.

According to the commands that are sent from the sender's mobile, send a signal through a buffer microcontroller/ By turning off the relay will actuate the respective weight. These relay a relay driver IC are inspired by the microcontroller interfaced.

In addition this project by sending an SMS, GSM modem, where the load can be controlled can be enhanced by using. This system works to eliminate the need to answer the phone.