I recently received the new Sonoff Zigbee Dongle Plus, primarily sold as a Zigbee coordinator. It’s a USB device – and you would plug it into a computer (Raspberry Pi for example) running for example Zigbee2MQTT. This unit would be the primary and only “coordinator” in a Zigbee network. Why this one? Well, Sonoff have been making such coordinators for years – and they keep improving while keeping prices reasonable… and providing good online documentation.
This new model claims to have a decent antenna and the latest and most powerful chipset. Unlike some earlier models, there’s no need to press buttons or open the case. The included 1 m USB extension cable helps reduce USB interference for a more reliable wireless connection (I learned the hard way that wireless 2.4Ghz devices should be kept away from USB hardware – shielding is important). As it happens, I use an RJ45 Ethernet-based coordinator so without interfering with my network I could not do anything with this as a coordinator – however it can easily be turned into a router without installing anyhing on your computer.
If you found that confusing – what Zigbee calls a coordinator performs a role that many people might think of as the network’s central router, while what Zigbee calls a router is more like a repeater or range extender. But there we are, we’re stuck with these terms – this isn’t Sonoff-specific – it is Zigbee-specific. As for what Zigbee routers are used for – well, unlike Wi-Fi, Zigbee doesn’t use your Wi-Fi router – and a coordinator and Zigbee2MQTT work together to make your Zigbee devices work with the rest of your IoT kit in, for example, Home Assistant. Signals from the coordinator are passed back and forth to devices such as Zigbee switches, lamps and sensors but the range is limited – hard to put a figure on it but in my cave-home for example, the signal barely gets beyond one room (very thick stone walls).
And this is where the routers come in. A device like this can be plugged into any old wall USB supply and will become part of the Zigbee network, so if you have a bunch of sensors at the far end of the house, out of range of the Zigbee coordinator, then one or more routers on the path between the coordinator and the sensors will ensure signals get back and forth.
Here’s where it gets slightly more complicated… as any mains-powered Zigbee device such as a smart plug or smart lamp – whether on or off – as long as it is plugged in – is also likely to be acting as a Zigbee router. All done by sleight of hand, you don’t have to set anything up – the network just organises itself as long as there are no major gaps.
Anyway, I’m happy with my RJ45 Ethernet coordinator so I plugged in the Sonoff unit to my PC USB and went to the Sonoff website and converted the dongle into a router – no buttons – no opening and moments after connecting and telling the site I wanted the unit to be a router – it was done.
I unplugged the unit, plugged it into a nearby USB power adaptor and went off to my Home Assistant Zigbee page (an optional integration in Home Assistant) and looked at the main Zigbee Overview. I clicked the “Permit Join” button in Zigbee and waited for the device to join. They normally appear momentarily with a long ID number at which point I rename them to something useful and there’s a tickbox to update the Home Assistant entity name to match.
WELL, as the Sonoff unit is brand new, when nothing happened I just assumed it had failed. It wasn’t until much later I just happened to go off to DEVICES tab – and lo and behold, the new device with its long, unhelpful number was in there. I renamed it and that was that.
But why didn’t it appear at the top of the device list in the home view? This was new to me and may be new to you…. devices that are ROUTERS ONLY, for reasons best known to the Zigbee2MQTT team are NOT shown in the Home view – only in DEVICES.
I did notice that when I clicked the device to get DETAILS it was marked as “unsupported” – that’s because at the time of writing it is not officially released. Sonoff Zigbee devices ALWAYS end up compatible with ZigbeeMQTT. Being impatient, I looked at my Zigbee2MQTT MAP which takes AGES to appear when requested as I have LOTS of devices on the network.
To show you this – I went to the main Zigbee2MQTT page in my browser, NETWORK in the list on the left, then MAP – and went off for some coffee (it really does take that long for my fast PC displaying Zigbee on my fast Home Assistant Mini-PC – several minutes). Ten minutes later, the complete map appeared (like that’s going to mean anything).
That yellow dot in the middle is my coordinator – everything starts there and branches out. Devices with only one wire going to them are end-devices – i.e. sensors. Then there are a few devices with nothing attached. Thats’ because they are currently offline. Down at the bottom right is an interesting one with LOTS of stuff branching off it…. I’ll zoom in..
At some point in the near future we’ll take another look at this map to watch as the number of connections grows automatically (sometime in August 2026 I expect).
Of course if you have lots of Zigbee plugs and lights you may not need a dedicated router at all, however they generally seem to have better range than many Zigbee lights and plugs thanks to their larger antenna and dedicated design and if your network is primarily composed of battery powered sensors – well, that’s another matter.
