Electrical Appliances control using PC’s parallel Port
Title of the project: Electrical Appliances control using PC’s parallel Port
Domain: PC Based Projects
Software: C Language
Optocoupler: MCT2E
Flip-flop: CD4013 D-Type
Relay: 5V, 100Ω SPDT
Power Supply: +5V, 500mA Regulated Power Supply
Display: LED, PC Screen
LED: 5mm White-in-Red, 5mm White-in-Blue
Input: Computer Key Board
Port: LPT1
ABSTRACT
PC based electrical appliances control is an interesting PC based project, mainly useful for industrial applications, home automation, and supervisory control applications. This project gives exact concept of interfacing a high voltage electrical device or DC / AC motor to high sensitive personal computer system. This project is the first step to design of PC based industrial automation projects.
Parallel port which is also called LPT or Printer port is used in this project for interfacing electrical devices to the computer system. A simple and powerful program is written in C, which sends control signals to the parallel port.
As, the PC is costly and sensitive system, it needs isolation from the high voltage electrical devices. A powerful technique of optical interfacing is used for interfacing both the devices. For this optocouplers are used in this project. Digital logic design is developed in this project by using flip-flops to turn on and turn off the electrical devices effectively. Reset function of flip-flops is used in this project to turn off the electrical devices at a time. This project also illustrates how to drive high current drawing devices such as Electromagnetic relays, DC motors and other inductive loads. Simple and powerful transistor driver circuit is designed to drive high current drawing devices.
This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.
BLOCK DIAGRAM
{Block diagram can be replaced with your owns}