There is no option to add an Ethernet option on the non E suffix ATV340 drives. If the Ethernet port on the ATV340.....E fails you can not replace the module its not replaceable. The non E suffix version or Standard ATV340 does support modbus but not Modbus TCP.
Only the E version of the ATV340.....E drive supports Both Modbus TCP and Ethernet IP.
On a side note only the none E suffix version allow the other option cards not the E suffix version.
1:) CANopen
2: )PROFIBUS DP V1
3:) DeviceNet
4:) EtherCAT
5:) ProfiNet