How many devices can a Conbee2 stick handle using ZHA?
I started to move over devices from IKEA gateway to Conbee2/ZHA because IKEA could not handle 50+ devices and stopped to respond accordingly.
Now I have moved 40+ devices to Conbee2/ZHA and after startup of HA it takes 2-3 minutes before ZHA devices is discovered.
With 20+ devices this was seconds.
As far as I know it doesn’t depend on the integration how many devices are supported, but rather on the hardware.
FWIW I have 80+ devices connected to a ConBee II and it works just fine. The limit is somewhere above 200 as far as I remember.
I believe that ConBee I/II can only have 20 “direct children” (Zigbee devices connected directly to the Zigbee Coordinator without going through a Zigbee router and thus instead of being indirectly connected).
If you only have Zigbee routers connected to the Zigbee coordinator then you will be able to add many more devices that will, in turn, be able to connect through them and by doing so offload the coordinator.
You should be able to have a total of one thousand (1000) devices that follow the older Zigbee Home Automation 1.2 specification in your Zigbee network mesh, but you might only be able to have a total of 50-200 Zigbee 3.0 devices in your Zigbee network mesh depending on CPU and RAM in the MCU (microcontroller unit) in your Zigbee coordinator because the security protocol for Zigbee 3.0 devices adds a lot of overhead.