Simple Wattmeter (for AC 230V)
A simple wattmeter, P18F2550 based, with minimal hardware. The software is written in mP (mikroPascal from Mikroelektronika).
It measures:
- the Rms voltage (unit: Volt)
- the Rms current (unit: Ampère)
- the apparent power consumption (unit: VoltAmpère: VA, the product of both the rms Voltage and the Rms current). This value is also called “Complex power”.
- the real power consumption (unit: Watt) (= the one that you are going to pay for)
- the power factor (no unit, ratio of real power to the apparent power), is the same as “cosΦ” (cos phi) for sinusoidal voltages and currents.

Updates from the author