Connection between MFM ABB M2M and plc PM573-ETH
Looking on M2M specification, there are different models, most of them with Modbus RTU, one with Modbus TCP/IP and one with Profibus. Also one type is without a protocol.
What is your type of device?
What do you need to read?
You can use all the tree protocols with PM573-ETH, Modbus RTU trough integrated COM port in AC500, Modbus TCP/IP trough integrated Ethernet port of AC500, for Profibus you will need additional Profibus module to the CPU. Also there are some analog, digital and pulse outputs of M2M, but I think that is not your case.
I can recommend Modbus TCP/IP or Modbus RTU (without a need of additional hardware) - it depends on the type of M2M.