ABSTRACT:
The main aim of the project is to design a versatile device that can control AC motor by using RF technology of wireless communication. This device can be used to control the speed and direction of the AC motor.
The RF modules used here are STT-433 MHz Transmitter along with an RF encoder HT12E, STR-433 MHz Receiver along with an RF decoder HT12D.
The project is designed in such a way that four switches will be interfaced to the controller to control the speed and direction of the motor. Two switches will be assigned to control the direction, and two more switches will be dedicated for sped control. And the RF transmitter is also interfaced to the controller through an RF encoder to encode the data received by the controller. Hence the encoded data will be transmitted by the transmitter over the wireless medium and will be received by the RF receiver which will be interfaced to the controller through an RF decoder, on the receiver side. The RF decoder is used to decode the received data into a 4 bit digital data which will be fed to the controller. And an AC motor will also be interfaced to the controller through a TRIAC. TRIAC reduces the energy flow to the motor and works very well for alternating currents. Now, it is the job of the controller to read the data received from the decoder and to perform the predefined task of rotating the motor clockwise, anticlockwise and increasing, decreasing the speed of the dc motor. 16X2 LCD is provided at the receiver side to display the status of the AC motor. This project uses regulated 5V, 500mA power supply. Unregulated 12V DC is used for relay. 7805 three terminal voltage regulator is used for voltage regulation. Full wave bridge rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.
TECHNICAL SPECIFICATIONS:
HARDWARE:
Micro controller : AT89S52
Crystal : 11.0592 MHz
LCD : HD44780
RF transmitter : STT-433MHZ
RF receiver : STT-433MHZ
RF encoder : HT12E
RF decoder : HT12D
AC motor
TRIAC
switches
Power supply
Transformer : 12V step down
Filter : 1000uf/25V
Voltage Regulator : 7805
SOFTWARE :
Keil microvision
proteus
UC flash
APPLICATIONS:
- Industrial applications