• 'BMX P34 2030' M340 PLC'.
• BMX NOE 0100 Ethernet module.
• OFS OPC server version 3.2.
• A PC running Windows XP, Service Pack 2
• 'Wireshark version 0.99'.6 Ethernet network protocol analyzer.
• A localized Ethernet network using a hub.

The 'Wireshark version 0.99'6' Ethernet network protocol analyzer was used to record sample
measurements of the response time for the 'Modbus TCP/IP' request because it provides a more accurate
representation. Even though the OFS Server diagnostics allows the user to view the response time of the
Modbus TCP/IP request, it is not considered to be accurate because of a delay in OFS display update.
The OFS Testing Client was configured to perform the following tests.

• Read 500 registers with a poll rate set at 100msec.
• Read 100 registers with a poll rate set at 1000 msec.

The tests results on the 'BMX P34 2030' M340 PLC' are shown below:



The tests results on the 'BMX NOE 0100' Ethernet module are shown below:




As conclusion, it can be seen the response time for a request being sent to either the 'Embedded
The Ethernet port of the 'M340 PLC' or its optional 'NOE0100' Ethernet module is very fast. The increased
load added by additional requests is also considered to have a negligible impact.

The additional time added to the NOE0100 response time as a result of the backplane processing is
also very small (about 2-4 msecs.). This can be seen in the results above by comparing the two charts
for NOE0100 Ethernet module against the M340 PLC.