When building industrial machinery and connecting PLCs, HMIs, VFDs etc over ethernet, is there any convention or guidance regarding IP address range choices?
We typically use 192.197.1.XXX. However, we bought a company 5 years ago, and noticed on one of their product lines, all machines are 169.254.1.XXX, and on their other product line 10.10.250.XXX.
We've had conflicts and been burned using the defaults of 192.168.1.XXX.
Does any one have any guidance why one would choose one over the other?

 

Hello,

Read the following page about IP classes:
https://www.meridianoutpost.com/resources/articles/IP-classes.php

Bertus

 

You have to use the RFC 1918 private IP address ranges (10.x.x.x, 172.16.x.x, or 192.168.x.x) for internal industrial networks. Avoid using 192.197.1.xxx or any public IP range unless explicitly provisioned for external communication.

 

169.254.1.XXX is very uncommon for a working product line, you normally only come across this on individual devices that are not set up properly with a fixed IP address: https://www.whatismyip.com/169-254-ip-address/