we have communication between Siemens S7 PLC and ABB 450 through serial interface using card CI532 V03. We are facing sometimes that communication hangs up and is reset by using MDB MVI 1 in ABB PLC. We are not able to figure out the reason for it.

 

> We are not able to figure out the reason for it.

And from that amount of information neither am I

First up - Is this a new problem? New Installation? Has anything changed?

Are you getting any errors reported by either controller? Connect control Builder to the AC450 and send the log messages to the screen.

What serial protocol are you using - Modbus or Siemens?

What are the indicator lights on the front of the CI532 doing. Do you get any activity at all when the link stops? Are there indicator lights on the S7?

What is the CPU load on your AC450?

Do you have a PC program controlling your CI532 interface? What happens if you Block/Reset that PC program? Does it restart the interface?

Rob
www[.]lymac.co.nz