Hi Robert

In your plugin on github i founded probably error.

there is
Volts_AB = self.rs485.read_float(0x2000, functioncode=4, numberOfRegisters=2)/10
...
should be

Volts_AB = self.rs485.read_float(0x2000, functioncode=3, numberOfRegisters=2)/10
...

for read modbus devices you shuld use ...