External reference

I am trying to do an external reference from one module to another and have never had this issue before, but here is the scenario...

I read the PV of a PID block either directly from the PID block or via a paramater wired from the PID block.  When I read the parameter from another module it is showing a value of 0 with red ??? beside it.  It is ran through a scaler block and the status of the input shows 'Bad NoCommNUV'.

Ive never seen this before and am doing this exact same thing in several other places with no issues at all.

Any suggestions?

3 Replies

  • Is it possible your external reference source exists on a different controller than your destination and your two controllers do not have peer-to-peer connectivity? 

     

    Make sure your external reference parameter is a read (not a write) if you are referencing a PID/PV.

     

    Can you provide screen shot of the issue?

     

    Youssef El-Bahtimy | Systems Integration Technologist
    PROCONEX | 103 Enterprise Drive | Royersford, PA 19468 USA
    Proconex Office: 610 495 2970 | Cell: 267 275 7513


  • I am talking across different controllers, and all communications have been OK for other talks of this same matter.
     
    I was performing a read from one controller to another and it was having the issue.  Again, other parameters in this same module work with no issue.  I did change the format and starting writing to the parameters from the actual PID module and is now working.  We are in process of converting some instruments from a Provox system to DeltaV, so there may be some status of the modules that are causing the issue.  Once the modules are fully converted I will try again and see what the results are.
     
    Thank You,
     
    Joshua Wooten
    Network Engineer |PLC & DCS Controls Programmer
    Microsoft Certified Systems Administrator (MCSA)
    M&G Chemicals | SR 2 Apple Grove, WV | 25502
    Office: 304-576-4553
    Mobile: 304-360-6051
     
    From: Youssef.El-Bahtimy [mailto:bounce-YoussefEl-Bahtimy@community.emerson.com]
    Sent: Tuesday, June 03, 2014 11:15 AM
    To: DeltaV@community.emerson.com
    Subject: RE: [EE365 DeltaV Track] External reference
     

    Is it possible your external reference source exists on a different controller than your destination and your two controllers do not have peer-to-peer connectivity? 

     

    Make sure your external reference parameter is a read (not a write) if you are referencing a PID/PV.

     

    Can you provide screen shot of the issue?

     

    Youssef El-Bahtimy | Systems Integration Technologist
    PROCONEX | 103 Enterprise Drive | Royersford, PA 19468 USA
    Proconex Office: 610 495 2970 | Cell: 267 275 7513
     
  • In reply to jwooten84:

    Try downloading changed setup data on each controller and the proplus.  The controller's keep a lookup table of modules that they host, so perhaps if the module is new, the setup data has not been properly spread across peers.