Power monitoring


I was just watching an EU based power monitoring video and thought I’l like to use some similar modules here. I’m ok with Raspberry Pi’s, most linux distros, even mac OSX, but refuse to touch Windows. I do have a neurio power monitor in my switch-box but it’s proprietary, and although I was monitoring the output for a while through a python script, it’s only useful as a whole house solution.

What’s the best and least expensive plug pack solution for power monitoring that has ESP32 type connectivity and would hopefully be compatible with OpenHAB or Home Assistant?


Hi Madivad,

I wanted to do the same, so when we built the house I bought a DIN rail power monitor from Schnap in Sydney Australia. It is similar to a Lanx Australis LXEM145 and it provides an isolated transistor output pulse. The one I bought gives a pulse output for every 2.5 WattHours. I have an ESP8266 connected to it, reporting to a MQTT server.
HTH David


You will need,

1x etherten

2x ct’s rated for “more” that what u plan to max out at, (they skew the results when u get over 3/4 the rated curent) (solid core is better but harder for average Joe to install) (set up your own bias resistors (not preinstalled)) To sample current draw…

2x small double tapped transformers (ie. 120vac in to 6v-0v-v6) for voltage samples

Assemble following the arduino DIY section…

If u need any help picking parts, or understanding the bias resistors let me know, I found my 400Amp ct’s @ Frys, and transformers @ Mouser…

U can output to mqtt or web server with minimal knowledge…

I’ll upload my “powermeter.ino” to my github later today and drop a link in here although the calibration numbers in mine will probably be different for you… (those come from trial and error with a multimeter and are per-install figures)

Mine is verified more accurate that the carrier grade zigbee based meters used in my part of the US… (I haven’t found a good way to read the GridstreamRF meters without power company complaints of lost signal)


I Might Upload pictures in the future if I get a free day to open it all back up…


I’ve used Efergy Engage Hub with a couple of Efergy Transmitter/ Clamps to monitor “whole of house” usage and “solar inverter” output and I use the Efergy Engage Dashboard on my Macbook Air and iPhone for offline history capture and spreadsheet analysis. I also use Home Assistant for online moniforing. HA’s discovery has picked up the Efergy data stream well and provides near real time loads as well as historical data that can be displayed as a trend using History Graphs. Ultimately I would like to use HA to time share (enable/disable switching) the big discretionary house loads - heated spa, washing machine/ clothes dryer, dishwasher. I plan to use Sonoff’s loaded with Tasmotta firmware talking both directions to HA via MQTT - still work in progress. Just one more thing - the Efergy is only a load indicator not a real power meter. Technical reason is that it assumes constant voltage and power factor of the load - not ideal but should be good enough for a first pass on the control algorithm. Hope this may be of interest. Cheers, Phil.

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