To communicate A9MEM**** / IEM**** energy meters with modbus communication using modbus:
1st Wire terminals D0 and D1 to terminals D0 and D1 of the serial modbus master.
2nd Configure the speed and parity data in the A9MEM.
1st wire terminals D0 and D1 and run them to terminals D0 and D1 of the serial modbus master.
Image taken from the installation manual:
https://download.schneider-electric.com/files?p_enDocType=Instruction+sheet&p_File_Name=NHA15801-06.pdf&p_Doc_Ref=NHA15801
2 Configure the speed and parity data in the A9MEM / IEM energy meter
The modbus mapping of A9MEM meters can be found on:
https://www.productinfo.schneider-electric.com/iem3100_iem3200_iem3300/iem3100_iem3200_iem3300-series_user-manual/iEM3100_iEM3200_iEM3300%20series_User%20Manual/English/BM_iEM3100_iEM3200_iEM3300SeriesUserManual_0000351220.ditamap
The following video tells how to perform a basic PM3000 setup: