ESPHome compatible "Smart Powermeter" supports up to 6 CT clamps - CNX Software

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ESPHome compatible "Smart Powermeter" supports up to 6 CT clamps - CNX Software

J.G.Aguado’s “Smart Powermeter” is an ESP32-S2 board with a 2.9-inch e-paper display designed to measure power consumption through up to six CT clamps, or Current Transformer clamps, that are each attached to one of the AC lines of a house or appliance.

I used an MT87 Digital Clamp Multimeter nearly 10 years ago to easily and safely measure the power consumption of a whole house by simply clamping it on one of the cables outside and reading the results on the display. The Smart Powermeter works in the same way but can perform measurements for up to six devices, and besides seeing the results on the display the ESP32-S2 can also send the data to the cloud or local server for data gathering and analysis using ESPHome or Arduino firmware.

The Smart Powermeter can be programmed with ESPHome firmware for easy integration with Home Assistant or the Arduino IDE for users wanting to develop their own firmware. You’ll find instructions to get started with either and more technical details on and GitHub.

J.G.Aguado used to sell small quantities of those on Tindie, but now the Smart Powermeter is available on Elecrow for $19.99 and up. But the lowest price is for the board only, and a complete system with display, enclosure, and six CT clamps goes for $61.96.

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.

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This is brilliant. I have been using a device I built myself to monitor power usage at a cottage but it was a pain in the butt. For $60 this is definitely worth it.

Yup! And clamps are so much safer than all those switches that (somehow) also measure power. Basically no skills needed to design this board and get it fcc/ce certified – even though I expect it not to be

It has potential, I also was looking for similar device – Zigbee option would be even better and a little bit more channels would be great to cover all exits of electrical cabinet (10 in my case) 😀 Also not clear, how complicated it could be to measure 3-phases with such meter?

Shame we cant power it with 120 VAC for the USA. Also how do you purchase more probes?

It’s my understanding that it works in the US too.

AC Input – 100-240VAC | 50-60Hz

You can search for “SCT-013 series” to get more probes.

ESPHome compatible "Smart Powermeter" supports up to 6 CT clamps - CNX Software

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