Emerson Exchange 365

DeltaV switchover Problem

I have a plant problem which when switch over happens in controller level, The modules which contains DC function block gives a alarm and this alarm produce a serious problem.

DeltaV Version: 8.4.1

The observed error description: confirm time error, unresolved reference

Be part of solution, not part of problem

brenet_1345

• 12 Oct 2013 12:19 PM
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4 Replies

• AdrianOffield

  

  • 12 Oct 2013 12:28 PM

  It sounds like you must be referencing an external point from another controller.  If you are, then you need to condition the external reference until the switchover has finished.  Use the .CST parameter of the external reference to determine if the link is good to use or use an ACT block with “abort on read errors” so the ACT stops processing while the switchover happens and the external references are still resolving.

   

  Hope that helps.

   

   

   

  From: brenet_1345 [mailto:bounce-brenet_1345@community.emerson.com]
  Sent: Saturday, October 12, 2013 3:20 PM
  To: DeltaV@community.emerson.com
  Subject: [EE365 DeltaV Track] DeltaV switchover Problem

   

  I have a plant problem which when switch over happens in controller level, The module with Dc block give a alarm and this alarm produce a serious problem.

  DeltaV Version: 8.4.1

  The observed error description: confirm time error, unresolved reference

  • Cancel
• brenet_1345

  

  • 13 Oct 2013 5:53 AM

  In reply to AdrianOffield:

  Dear AdrianOffield, Thanks for your reply, but actually the problem is in switchover-ed controller not another controller. The message parameter for this alarm was "Confirmed time". I have done a bit further search in internet and find following Issue:

  Incident: 52190

  >>>

  Description: On a controller switchover the DC Function Block back calculates the SP value from the state of the outputs. This can present an incorrect alarm if the “Passive on Active Confirm” option is selected and the device is in the Active State when a switchover occurs.

  Current Status: This Issue has been resolved.

  <<<

  But I couldn't find the relevant HotFix number which resolved the issue.

  Be part of solution, not part of problem

  • Cancel
• AdrianOffield

  

  • 13 Oct 2013 9:21 AM

  Yes, I am also referring to your “switchover-ed” controller, inside this controller there can be external references to “other controllers”.  These links are what I’m referring too, and you need to condition for switchover behavior.

   

  If you don’t have any external links then, obviously, this not related to your problem.

   

  The DC block goes through initialization on switchover, so please check how you handle your inputs, perhaps one of the inputs are dropping on switchover.  I’ve had a problem with FF DO blocks and topworx valves and the DC block referencing the READBACK_D of the DO block.  On switchover, the READBACK_D value would initialize, causing the DC block to see a “failed confirm”.  

   

  This has since been rectified in CTRL14 for 10.3.1 - TFS130940

   

   

  From: brenet_1345 [mailto:bounce-brenet_1345@community.emerson.com]
  Sent: Sunday, October 13, 2013 8:54 AM
  To: DeltaV@community.emerson.com
  Subject: RE: [EE365 DeltaV Track] DeltaV switchover Problem

   

  Dear AdrianOffield, Thanks for your reply, but actually the problem is in switchover-ed controller not another controller. The message parameter for this alarm was "Confirmed time". I have done a bit further search in internet and find following Issue:

  Incident: 52190

  >>> 

  Description: On a controller switchover the DC Function Block back calculates the SP value from the state of the outputs. This can present an incorrect alarm if the “Passive on Active Confirm” option is selected and the device is in the Active State when a switchover occurs.

  Current Status: This Issue has been resolved.

  <<< 

  But I couldn't find the relevant HotFix number which resolved the issue.

  • Cancel
• cbpun

  

  • 18 Oct 2013 3:56 AM

  Hi All, I am not very sure whether DeltaV supports following capacity:

   

   

  1.    Given 10 standard PID Control loops with a 500 msec. Can this be achieved ?

   

  2.    multiple clients to access up to 12 servers or 12

           redundant pairs of servers. Is this possible in deltaV Control Network?

   

  Regards.

   

  From: brenet_1345 [mailto:bounce-brenet_1345@community.emerson.com]
  Sent: Saturday, October 12, 2013 8:20 PM
  To: DeltaV@community.emerson.com
  Subject: [EE365 DeltaV Track] DeltaV switchover Problem

   

  I have a plant problem which when switch over happens in controller level, The module with Dc block give a alarm and this alarm produce a serious problem.

  DeltaV Version: 8.4.1

  The observed error description: confirm time error, unresolved reference

  • Cancel