You can use ETH_MOD_MAST block in your AC500 PLC. Seperate blocks for read and write can be used. As said aove the schneider plc supports modbus tcp ip, it is simpler to configure.
Remember to configure on schneider plc too.
With fast browsing and googling the Schneider PLC it seems that their ethernet slot can
communcate using modbus tcp.
That is also a deault on a AC500 PM583 plc internal ethernet slot.
So I would recommend using this for transfer.