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Inserting a parameter to existing process history view for continuous trending

Hi All

How do I edit a .phv   so as to include another parameter such that it is trended continuously even if I close the Process history view in DeltaV run mode and reopen it again. I tried to open process history from a faceplate and included a parameter to be trended but it disappears when the view is closed.

Thanks

Arthur

chigarthur

• 19 Apr 2016 10:42 AM
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3 Replies

• iam5113

  

  • 19 Apr 2016 11:46 AM

  You have to save the view to the .phv file before you close Process History View.
  It's better to have pre-defined trends saved to each workstation rather than do anything ad-hoc, although DeltaV's standard display objects from v11 onwards have a nice right-click functionality to add the module's PV to the trend builder, then open it up in Process History View 9oh, and the SP and OUT for controllers too).
  This does allow operators to quickly trend 2 or 3 values very easily, but the view is lost if they don't then save it.
  If you're not using the standard display objects, it is possible (but not easy) to copy the standard right-click functionality from a standard object and use it on your own objects (I've done it, but can't remember how).

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• wpettit@fce.com

  

  • 19 Apr 2016 1:27 PM

  In reply to iam5113:

  I am not sure but it also sounds like you are asking how to add a point to the historian so that even when the trend is not open the data is being collected and can be displayed when the trend is again opened. If that is the case you need to go to the module in DeltaV explorer right click and add the data point to the historian then save and download and last but not least download the application station historian. That way when you open the trend again historical data will be available while the trend was closed and the trend can be opened and closed and the data will still be there hope this helps.

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• Andre Dicaire

  

  • 19 Apr 2016 4:42 PM

  There are several things being discussed here that should be clarified.
  
  PHV is the DeltaV Historical client application where trends and events are displayed. PHV Trends can combine historical data with real time data so that a parameter can be trended even if it is not defined in the historian.
  In order for a trend line to show historical data, the parameter must be collected in the historian. When a PHV Chart is called up, it begins plotting the current data using the real time OPC connection on that workstation, and also contacts the history server for any collected data for that parameter. If there is not history, the trend continues to populate and store the parameter in what is referred to as a Real Time Trend. Refreshing or reopening this Chart will result in loss of this collected data.
  
  As Wpetit below explains, in order for PHV to show history collected data, you must add the parameter to the history collection. This is done by adding the parameter to the history collection in host module. The module is part of a plant Area, which must be assigned to the Continuous Historian, to which PHV is pointed to. You must download the continuous historian once the parameter has been configured for collection. At this point, history collection will start.
  
  PHV has preconfigured CHARTs designed to function with different types of modules. The relationship of which Chart works with which modules is based on the assigned faceplate display for the module. The name of the Faceplate display is used to name the corresponding CHART in the library. The Faceplate has a PHV Button that launches this PHV Chart, passing it the module name. This library CHARTs use a wildcard specifier called "@mod@", and when the chart is launched, the module name is substituted in this library CHART to show the predefined variables for that module.
  
  PHV also has user defined CHARTs, which can contain any 8 parameters in the system, and if these have history data collected, will show history when called. Users can create and save these charts on any operator station. There is a user privilege required to save charts, but users can add parameters to any open CHART as needed.
  
  If you launch a CHART from the Faceplate icon, you can add a parameter to the chart but you can not save this path to the library CHART. The library CHARTS must be configured using the @MOD@ wildcard. When adding a trend to a chart, at run time, you must use the module name to see the data, and this would not be the right format for these library CHARTS.
  
  In a User Defined CHART, you can save the CHART and be able to recall it later, with the defined paths, and retrieve the history for those parameters that are being collected.
  
  So, to the specific question above, if you wish to add a parameter to the library Chart associated with a specific module type, you must edit and save the CHART on the Professional Plus and use the @MOD@ qualifier for the module name. for example, if the Module in question uses a specific .GRF file called FP_LOOP.GRF, then you must edit the Library CHART called FP_LOOP.PHVE (the extension may vary). Save this file and download to the operator stations. All modules that use this same faceplate will now show the new parameter. Also, the parameter must be in the module, and should be in all modules that use this same faceplate and Chart.
  
  If you are trying to combine parameters from different modules, the library Charts are not intended for this. You should use a User defined CHART to combine the various parameters as needed, and then use a button on a display to call up this view of the data, or you could embed this as a chart directly in a display.
  
  The thing to remember is that Library Charts are intended to work with a type of module, based off a Class or a Module template, and all parameters in the chart are present in that module type. If you want to create a unique CHART for a module, you'll need to create a new faceplate file and associated CHART with the same name. Copy the existing faceplate and CHART and assign this faceplate to the module or modules that will make use of the new CHART. Modify the CHART to reflect the data you want to show.
  
  Hopefully this helps you understand how the CHARTS work with Faceplates and where you might want to make changes. You might want to get some assistance before you start modifying the library CHARTS and end up with undesirable behavior in other modules. Once you understand these interactions and dependencies, you'll be able to plan your changes.

  Andre Dicaire

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