I was mighty impressed with Sonoff MiniR4 (Extreme) size and design. One of the smallest WiFi relays to handle your in-wall switching. I hoped the MiniR4 was the beginning of the Extreme overhaul and it looks like I had been proven right. The next device on the ITEAD list for making stuff smaller/better is the Sonoff ZBMiniL2 (extreme). It brings 2 of my favourite features in one tiny package.
Sonoff ZBMiniL2
If you know how to decipher ITEAD product names, the presence of ZigBee 3.0 and no-neutral requirements won’t be a surprise to you. Sonoff ZBMiniL2 is in fact, a redesign of an older Sonoff ZBMiniL – a popular ZigBee in-wall really – with a much bigger footprint. Right now, I’m confident to say, that we should see more devices in the Extreme lineup soon (even though I have no official confirmation from ITEAD).
Sonoff ZBMiniL2 is a tiny in-wall single-channel relay that fits behind a light switch and requires no neutral wire to be plugged in. All automation fans in the UK (and countries with similar wiring standards) rejoice! What you have – is essentially the same (in function) device as Sonoff ZBMiniL, in a much smaller form. Measuring 37x19x32mm, the device is much smaller than the original ZBMiniL, but 2mm thicker than the WiFi equivalent.
It’s rated for 6A resistive load and it comes with all terminals needed to connect it straight to your in-wall switch. One button acts as a pairing button and the device toggle.
Inside Sonoff ZBMiniL2
WARNING: the device has the ability to store current after it has been disconnected. To avoid getting shocked, unplug it, then activate the relay via the switch a couple of times until residual power is discharged. You will hear the internal relay working even if the power is disconnected.
Curious to see what was on the inside, I opened it up. It’s really easy to remove the plastic casing. Sonoff ZBMiniL consists of a main PCB and 2 daughter boards one for the 8A relay (this time I was able to verify the relay model) and a separate board for handling ZigBee 3.0 signal with EFR32 MG22 IC. You probably remember this IC from my review of the new and improved Sonoff ZB Temp & Humidity sensor. Something tells me this is not there last time ITAD’s products will feature this IC. Sadly, this relay, despite being connected to mains 24/7, can’t be used as a router to extend ZigBee mesh – we have to thank no-neutral connection for this limitation.
The ZigBee daughter board has a couple of depends if you want to tinker with that, but as Sonoff ZBMiniL2 is ZigBee based, I don’t believe a typical DIY home automation enthusiast would need to play with its firmware to get it to work. Everything inside is densely packed, leaving no space for anything else.
Pairing and use
I used my Sonoff ZigBee Bridge to get it paired with my eWeLink account and had my first playtest there. The pairing process is uneventful and the device once is in pairing mode (hold button for 5 sec) connects in seconds. It’s worth mentioning that without pairing, I had problems operating the physical switch.
Inside the eWeLink app, we have a typical single-channel relay interface. At the time of writing, the setup for Sonoff ZBMiniL2 offered only schedules, times and loops. No additional switch controls were present in the settings. To change the switch mode from push to toggle, you’ll need to toggle the pair button 3 times – make sure to set the correct mode in advance.
Of course, thanks to eWeLink app integration with Alexa and Google services is possible and works without a hitch.
The relay responds rapidly to both, the input from the switch and the cloud/hub interactions with the app updating the interface promptly. In short – it works as it should.
Power consumption
Sonoff ZBMiniL2 doesn’t have a power meter function, not a massive issue as the switch will be connected to a source with fixed power consumption. You can get estimated consumption using my flow in NodeRED. The device alone has a minimal power consumption of its own.
My meter would not register the draw in the power-off state and reported a 0.1W difference when the lights were on. It rings true for all ZigBee-based devices tested in my article about the cost of home automation.
Other ecosystems?
I tried to pair the switch with Aqara, without luck, but Tuya worked beautifully without any issues. Feel free to add Sonoff ZBMiniL2 to your Tuya ecosystem. My guess is, and that’s a guess as I have no Echo devices with ZigBee routers inside them, it should work just fine in the Alexa ecosystem without skills. Don’t blame me if that’s not going to be the case. The safest approach is to try ZigBee2MQTT and that’s the next chapter.
Sonoff ZBMiniL2 in Zigbee2MQTT
My Sonoff ZBMiniL2 arrived late, and it looks like it’s already supported by ZigBee2Mqtt – so using it in your own home automation is a breeze. Shows up in the Zigbee2MQTT dashboard correctly and you can start using it without any problems. The payload just supplies basic information:
{"linkquality":145,"state":"OFF"}I tested mine with Sonoff ZigBee Dongle with a firmware I recommended to use in this post. But any other coordinators like Electrolama’s ZZH should work too. This time around, I was feeling lazy and simply re-used my Aqara relay NodeRED flow to give it a quick test. I also discovered some bugs in the code, so a new version of the project is coming soon as well!
Shop with Sonoff
Take a look at the ZigBee and WiFi range of the devices compatible with eWeLink:
Final thoughts
It looks like Sonoff ZBMiniL2 is also reasonably priced – you can order yours for $13.99 with shipping starting in the 2nd half of January. For now, I’m happy that DIY automation enthusiasts have one more ZigBee 3.0 switch to look forward to – and that’s good news. Thoughts or questions? Feel free to leave it in this Reddit thread.
🆓📈 – See the transparency note for details.
