Matter support for the emonTx v4

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After some tinkering with my emonTx v4, I created an ESP32 Firmware that allows me to expose the 6 CT clamp power readings via the Matter smart home protocol! It leverages the UART expansion header on the emonTx and reads the serial data,

Support for the Matter Electrical Sensor is a bit limited, but my Aqara hub supports it.

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I’m tinkering with a Matter based energy manager, which prompted this little side project.

All the code is up on Github, but the repo is private at the moment as I need to tidy up the README etc.

I’ve written the whole thing up here - Adding Matter support to the OpenEnergyMonitor emonTx v4 – @tomasmcguinness

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Nice @tomasmcguinness - which ESP32 did you use? We’ve made an ESP32 adapter for the Tx4, Tx5, and Tx6 to fit into their respective UART ports. Should be available soon from the OEM shop.

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That’s exactly why I went on a C6 for my mk2Wifi module… To be able to cope with matter and thread.

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What is your mk2Wifi module?

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ESP32-H2 to start

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Nice, the -H2 looks very similar to the -C3 we’re currently using.

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For my PCB, I’ll use a C6, probably the SuperMini board for simplicity. The H2 is designed for low power scenarios, which this isn’t. I just happened to have an H2 DevKit on my desk :rofl:

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That’s a similar module like the emonWiFi but for the mk2pvrouter.

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I’m thinking if we went for a C6 instead of the C2 on the emonWiFi this would be easily extendable with ESPHome.

However, I’m not sure I see the point in a home environment of Matter/Thread/Zigbee over WiFi for the emonWiFi.

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Well, for some situations like at home, that’s quite an advantage to go over a mesh network like zigbee or thread.
Thread supports ipV6 too.

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I really like Thread because there is no longer a single point of failure in the network

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Sure, that’s another point!

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Except at the point where it enters the HA system (unless you have 2 dongles) :rofl:

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Not sure I follow?

Outside of my Thread network and its border routers, my network switch is a single point of failure for most scenarios.

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This assumes you have multiple Thread Border Routers already then. Not everyone will have so still a single point of failure.

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Well at some point, to avoid single point of failure, you’d need full redundance, as in an industrial installation.
With my experience, thread/zigbee devices are really less prone to connection lost than pure wifi devices, as long as some of these devices act as routers.