Browse FAQs

Why can I not connect to my PLC over Modbus Serial?

Published date: 30 May 2019

Connecting over Modbus Serial

Product Line

Modbus Serial

RSLinx conflict

If you cannot connect to your PLC over Modbus Serial you may have Rockwell Drivers/RSLinx installed on your PC. The Rockwell software takes full control of the COM port and will not allow anything else to communicate out. The Rockwell software needs to be completely shut down to free up the COM port. 

Was this helpful?

What can we do to improve the information ?

Can't find what you are looking for?

Reach out to our customer care team to receive information on technical support, assistance for complaints and more.