Emerson Exchange 365

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DeltaV Historian

Hello,

   I'm about a year into using DeltaV, programming and modifying operator interface, etc.  One problem that has come up recently is that when am Operator/User calls up the Process History trend function to view the history of a tag value,  when they click on the trend, the vertical cursor line appears on the trend at a point an hour later than where they click.. It's like there is a 1 hour bias applied somehow.

  I've noticed that the time down below the trend in the timestamp is always agreeing with where on the trend you actually click.

  And to add another quirk,  if you click somewhere right on the trended line itself, the cursor line will appear where you click, but the time down in the timestamp area is now an hour LESS than where you clicked!

  Searched a long time for anything that would account for this.  Rebooted Historian PC< Engineer Work Station PC, OPC PC, none affected the issue.

  So, any ideas?  Thanks in advance

Ralph Kitts  

Ralph Kitts

• 10 Mar 2022 1:46 PM
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4 Replies

• Andre Dicaire

  

  • 10 Mar 2022 3:44 PM

  The History data is stored in UTC time and displayed at the console using the workstations Time/Date settings, including behavior for daylight savings time. I haven't seen this behavior, but I would definitely start by making sure all the time zone settings and Daylight savings time settings are all set the same, and then make sure the Time has been adjusted correctly.
  
  Is the behavior seen on all workstations? Do you have the latest version/hotfix installed? I'd suggest you explore these settings on the workstation side and align with the server and see if you can identify what may be causing this. Once you know what the source of the issue is, you can evaluate if any changes to the server should be made. Changing time settings on the server can impact how the past data is displayed and you should understand that before making any changes there.
  
  Have you logged a call with the GSC? If this is a known issue, the GSC can help identify it and any workarounds or hotfixes to address it.

  Andre Dicaire

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• Ralph Kitts

  

  • 10 Mar 2022 3:55 PM

  In reply to Andre Dicaire:

  Thanks for the advice, Andre. I will dig into these and get back with what I found.
  
  All workstations are showing this behavior, and all have their time set by the EWS (Time master).

  Ralph Kitts  

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• Don Dron

  

  • 15 Mar 2022 9:17 PM

  In reply to Ralph Kitts:

  Install the latest workstation hotfix, it will fix this issue.

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• Ralph Kitts

  

  • 16 Mar 2022 10:56 AM

  In reply to Don Dron:

  The problem corrected itself.
  
  The correction occurred at Daylight Savings Time.
  
  Since the EWS is the Master Timekeeper and was itself set to for automatic for Daylight Savings Time, I'm still at a loss as to why this occurred.
  
  I will implement the latest hotfix as soon as possible.
  
  Thanks for all your suggestions :-)

  Ralph Kitts  

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