The block diagram of the project Power Measurement using Arduino is as shown.
The load circuit consists of resistive loads which are bulbs each of rating
200 watts.
These loads are energized by single phase 230V AC supply.
The current and voltage through the load are stepped down to safer values by using a current transformer and potential transformer respectively.
As the AC signals can’t be given to Arduino board, these signals are offsetted using voltage and current offset data conditioning cards. These cards are energized using regulated DC supply.
The function of offset data conditioning cards is to clamp the AC signal with respect to a preset reference DC voltage.
The output waves from the voltage offset card are given as analog input to Arduino board at pins A and ground.
Similarly the output from the current offset card is given as analog input to Arduino board at the pins A and ground.
Once the analog inputs are given to Arduino and the measurement of power is done by Arduino sketch