mousa

In this project i used arduino and XOR gate to power factor measurement. What is power factor? Power factor is a number between 0 and 1 refers to phase shift between voltage phase and current phase in AC appliance. How to measure PF with Microcontroller (Arduino)? To measuring the power factor with microcontrollers in the first we used Op-Amp to zero cross detection to find the phase shift between current and voltage phase, the op-amp convert the sine wave signal comes from CT and PT with different amplitude to square wave with about 4v amplitude, then we connect these two square wave to XOR gate inputs.  XOR gate output will be 1 just when the inputs have different signals so when the load is resistive XOR gate output is 0 because both voltage and current phases start and ends in the same time, but when the load is inductive or capacitive XOR output is 1 because there are phase shaft between voltage and current, Hence we can find the power factor by measuring the " ON-time "