If you want to calculate RMS current, you need to sample the voltage of the CT waveform many times over ONE cycle of the AC line, and calculate the RMS value from its definition, sqrt( (1/N) sum (V^2)). Then calculate the current from the RMS voltage value after scaling. Oct 02, 2018 · Safe and easy DIY Home Energy Monitor Using Current Transformer with Arduino, Raspberry Pi, or Beaglebone Black To measure and monitor the energy usage of home appliances, let us build a simple and basic energy monitor.

Jul 16, 2011 · The other day, I needed to measure the AC current of my water heater without having to disconnect the wiring. Typically, you would need a clamp meter to do this. Since I don’t have a clamp meter, I thought I would just make a simple current transformer myself. In fact, making a current transformer is a very easy task. A home-brew current transformer made from a split ferrite core and some magnet wire is the sensor, and a couple of op-amps and a 555 timer make up the detection and alarm part.