How do I change the Baud Rate of a field bus (either Infinet or Bacnet MSTP) if there is either an Infilink or B-link on the network?

Issue

How do I change the Baud Rate of a field bus (either Infinet or Bacnet MSTP) if there is either an Infilink or B-link on the network?

Product Line

Andover Continuum, SmartStruxure Solution

Environment

  • Infinet
  • BACnet

Cause

The Infilink and B-link must have their baud rate set manually.

Resolution

All Infinet or Bacnet B3 controllers autobaud on initial startup or when the fieldbus commport is changed from the parent controller's commport editor.

The Infilink and B-link must have their baud rate set manually.

The proper procedure to change the fieldbus baud rate is to first go to the commport editor and change the fieldbus baud rate. At this point a message is sent to all field bus controllers to change their baud rate. They will all change immediately, however the Infilink and B-link have not yet changed, so the bus will now be in a confused state and there will be offline issues. The next step is to go to the Infilink or B-link repeater and manually change the baud rate to the new setting.

At this point the network should work normally, however if the procedure is not followed there may be network issues where you have some controllers that are running at different baud rates causing the network to be totally shut down. If this is the case the way to resolve the issue is to make sure the Infilink or B-link repeater is set to the desired baud rate and power down or reset those controllers on the network so that they will all synch up to the correct Baud Rate upon power up.

** Changing many controllers

  1. A method that may help when needing to change the baud rate of many controllers is to bypass the b-link
  2. Connect segment 1 of the b-link directly to the BCX comm port and change the baud rate
  3. Reconnect the B-link and verify the controllers are now online, repeat the baud change if necessary.
  4. Repeat this process for each segment
  5. You may still have some isolated controllers that need to be powered off/on.

Related: Lessons Learned Article #13759