Beckhoff EL72 1 Series Documentation page 56

Commissioning
IP address of the port used
IP address/DHCP
In most cases an Ethernet port that is configured as an EtherCAT device will not transport
general IP packets. For this reason and in cases where an EL6601 or similar devices are
Note
used it is useful to specify a fixed IP address for this port via the "Internet Protocol TCP/IP"
driver setting and to disable DHCP. In this way the delay associated with the DHCP client
for the Ethernet port assigning itself a default IP address in the absence of a DHCP server
is avoided. A suitable address space is 192.168.x.x, for example.
Fig. 49: TCP/IP setting for the Ethernet port
56 Version: 3.3 EL72x1