I’d like to measure the energy passing into and out of (we export energy from solar) our house in the UK via the meter. Our meter has a pulse light but only for consumption so I think our only option is for a current clamp.
I’m seeing fairly cheap Tuya Zigbee clamps (~£15) on eBay (e.g. https://ebay.io/m/iv235t ) but some of them, as per this example, explicitly say they’re not compatible with HA which seems odd. Can anyone say whether these cheap clamps are worth it or best avoided?
Actually, looking at that Tuya device, it is mains powered and as the meter is external, I don’t have convenient access to mains power. Therefore, I would need a solution that is battery powered…
Hi, be aware that integrating Tuya can be a PITA.
Is your mains power meter mains powered? They usually are.
Maybe the power monitor could be too? Do you need your electrician to install a power outlet, or can it be hard wired when the monitor is installed? Often if they are DIN mounting, they can be co-located with your meter in the same box.
Do you have to install separate metering at all?
Ask your retailer if your meter is smart and measures flow both ways, so your bill has the correct amount for solar feed-in (amazing they pay you a different amount for what you supply, compared to what you consume), and if that raw data is accessible. Often the data is available via a data portal and there are integrations to get the data into HomeAssistant without any wiring or equipment required.
You didn’t share the model of your existing meter and name of your electricity retailer, so we cannot give any more detailed suggestions on that aspect.
Be aware that cheap devices sourced from China and Tuya compatible are carrying your entire household current and should be appropriately rated (and trusted).
Getting the data from a ZigBee device requires further infrastructure you need to factor into your home automation ecosystem. Do you go Matter/Thread instead, WiFi, or even RS485/ModBus? How do all your other devices interact with your HomeAssistant server? Do you need added devices such as a hub to relay signals?
Tuya compatibility can be patchy, and who do you call for technical support if your cheap chinese device, selected based on lowest price, built on a dimly lit kitchen table by child labor, using the cheapest parts available from the local weekend market, has problems? Consider other vendors such as Shelly and Zemismart that offer full HomeAssistant integration out of the box without a lot of consternation, have full technical documentation, a support team at call, and a reputation to maintain.
How could that be done? You can’t measure energy by monitoring just current. You need to measure voltage as well and separate active power from reactive power. These can be done only by mains connected device.