M-Bus (Meter-Bus) library and examples

[Zen]

RTU is Modbus, not M-bus. Don't enable it for the port that you want to use for M-bus.
Only a single script must access the port at any time. Simply reading data from the port won't produce anything. Meters won't send anything without a request from the gateway.
Most likely you need to set short addresses as stated in the integration guide. Connect only one meter to the bus, set the short address then run the scan.
Also only one GND needs to be connected.

Hi admin, thanks for the fast reply. 
For both GND i meant that i've connected the GND pole of the MBus Gateway to the GND pole of LM5/RS232 (the last on the right). I've tryed right now to set the short address but i've got the alert error "[mbus] failed to change short address to 1 no reply" triggered by the script and i've tryed out 0,1,2... to 10 as value.
Obviously i've connected only one meter.
Thank you