What would optimal 3-Phase setup be?


I currently have emonPi monitoring my grid and solar and love it, a big shout out to all the people that have contributed to OpenEnergyMonitor!

I’m moving to 3-phase (and probably battery storage) and I want to implement the optimal OpenEnergyMonitor setup. What does that look like in 2020?

I was thinking of getting the electrician to install 3 x AC sockets in the meter box, one wired to each phase for the voltage sampling.

Not sure how relevant it is but I’m happy in Linux, would prefer wired connectivity and can solder SMT.

What are people doing?


I don’t think it will be much different from 2019. :laughing:

That’s essential.

That will be a very useful skill.

The optimal setup would be one emonTx monitoring each of the three phases, and treating each as a single-phase installation. Depending on how many individual loads you want to monitor, you might need more than three. But wired won’t be easy, as the emonTx only has a RS232-type wired output available. I know you’ve written that you love emonTx, but if you feel you’re in danger of acquiring too many, you could think about developing your own front end hardware, and then I’d look hard at the dedicated energy monitoring i.c’s and use a processor to collect the data and send it on to (say) a RPi (or any server) running emonCMS or whichever dashboard you choose.
It’s in emonCMS (or whatever) that you’d gather together the data for 3-phase loads, for example.

When you think about battery storage, you’ll probably want an inverter/charger that’s capable of reporting its data to your system.

I’m not clear what you have in mind, so that’s about all I can say.

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Thanks, is there a way to have 3 x emonTX be wired into something that converts the serial to ethernet, that I could aggregate somehow and send to the CMS?

The ESP8266 module does what you want for WiFi. For wired, you could move to the emonTx Shield and an Ethernet-equipped Arduino, or a plain Arduino with both Ethernet Shield and emonTx Shield; or there are serial to Ethernet converters available for your emonTx, but they’re not cheap and I’ve no experience of using them, nor can I remember seeing any mention of one here.