Theoretically 1 leader , 32 router and 511 per router , I am yet to implement practical, got delayed due to corona , can 30 modules be interconnected in nrf52840
Yes, there should not be any problem having 30 thread devices on a network.
The practical maximum number of devices on a Thread network will depend on many things, like how much data and how often you want to send data, and how the nodes are connected to each other, so it's impossible to know the maximum number of nodes in a network, but we have had customers with solutions with around 1500 nodes in use at any time e.g: https://blog.nordicsemi.com/getconnected/thread-connected-hangers-in-a-parisian-boutique
The default max children in the nRF Thread & Zigbee SDK is set to 32, but you can recompile the OpenThread stack and change this if you want to experiment with more than 1056 devices.
One more doubt, if a node gets reset or disconnected , due to power failure, dose it need to get configured again to join the mesh or it will connect to mesh by itself later when switched on ??
For the CLI example you will need to configure the node again, this is just part on how the example has been created for easier debugging so you can use it to develop your own applications. But in all other examples the devices are pre-commissioned, which means the network data is stored in flash and the node will rejoin automatically after a reset.
