RMS measuring sensors

Hi everyone, this is my first post here. I've been looking for a sensor (power meter) that can measure the RMS value of Voltage/Current as well as Active and Reactive power in order to relieve my Arduino from doing all the heavy calculation. Does anyone know of anything that can meet those requirements?

Thank you very much

Such meters are available commercially, for a price, e.g. https://www.amazon.com/3-Phase-Correction-Multimeter-Reactive-Frequency/dp/B07FW28BBF

Much cheaper to buy a Pro Mini and dedicate it to the task (about $2 on eBay).

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Check out Open Energy Monitor.

As long as you know you have a sine wave there is a known ratio between RMS and peak (and between the RMS and average of the absolute values) and that's a simple calculation.

Most multimeters simply assume you're measuring a sine wave but there are meters that measure "True RMS".

You will need to fined the phase difference between the voltage & current.

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Check this out: real time power . I'm not sure it's true RMS but it seems to cover other functions at a reasonable cost.

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They are available but the good ones do not come inexpensive. Before I retired I used a good amount of sensors from CR Magnetics. There are dozens of manufacturers to choose from. I also used sensors from Ohio Semitronics and again not quite inexpensive stuff. Nice feature about the latest and greatest stuff is communications as many can be had with a data out bus.

Overall while nice stuff unless you are a company with deep pockets using a simple inexpensive Arduino or similar for hobby applications is the way to go. :slight_smile:

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That was exactly what I was looking for. Thank you very much :smiling_face_with_three_hearts: