HMI & CPU IP Addresses

[dierkens]

Quick question that I've been asked about a few times by clients and other controls engineers that I have a 'hard time' answering.

We assign an IP Address to both the CPU and the HMI but we only ever use the HMI Address for anything such as MODBUS/TCP communications, VNC, FTP, etc.

What's the purpose of the CPU IP Address if we never use it for anything?  

It' nice that the 2 ports are actually into a switch but if we can't really use the other IP Address then what's it for?

This tends to come up when we need to communicate/access the PLC over different networks.

[Joe Tauser]

From the Help - 

 

Joe T.