Power factor and current measurement

Thread Starter


Joined Nov 14, 2009
I need to design home energy monitor using Hall Effect sensor. The circuit encorporates current sensor, precision rectifier, A/D Converter,μcontroller, display monitor etc. Question is, how do I measure the Power factor and Current(since it has been converted to proportional voltage) for the load. I Appreciate any advice. With thanks


Joined Aug 26, 2009
Pretty much every vendor that sells Hall effect sensors that are intended for power measurement has an application note that describes in detail how to use their sensor for that purpose.

If you're trying to use a sensor that's not designed for power measurement ("power metering" isn't listed on the first page of the datasheet as one of the inteneded applications), then it won't be a great sensor, not would they have app notes for it. In that case, go to a vendor that does sell such chips and check out their app notes. Teridian, Microchip, Atmel, TI and Analog Devices immediately come to mind. Everything that you need to know is almost certainly in any one of them.