since Version 2023.9.0 and 2023.9.1 of Homeassistant has IamMeter no connection to HA.
There is no function via offical Homeassistant Integration / Hacs via Cloud Integration / Hacs via Modbus Integration.
Tested with the new Firmware .68 and the older Firmware .66
Back to HA 2023.8.4 -> Everything works
I am facing the same issue. Tried every configuration in HA but after some connection, it got broken again and again. Upgraded to new firmware and now IAMeter is not responding at all.