Hello,
I'm trying to provide a list of history tags from a DVCH historian (v14.LTS) to be imported into a PI system for collection. Generating the list of tags is easy, but the this PI team is asking for parameter data types. Is there a way to get the data type for parameters out of a module aside from a manual expedition?
Thank you
Not directly. The DVCH is able to discover this and scaling information automatically at run time to create the required information in the historian. So DeltaV does not have a convenient export of all the history tag information. I believe there are external tools that have been developed to extract the data from a database FHX. I don't have access to these. maybe someone can share.
have a look at DVCHDump.exe. located in the DV utilities of the C drive. It is a command line interface tool. You can redirect the output to file when you run this from the command line.
One option is - C:\dvchdump configuration. This gives the following results:
DeltaV=PW1-PROPLUS PIC1-1110/PID1/OUT.CV Float Continuous Automatic 1sec Comp=[SlopingBoxCar 1] Max=14400 DeltaV=PW1-PROPLUS PIC1-1110/PID1/PV.CV Float Continuous Automatic 1sec Comp=[SlopingBoxCar 2] Max=14400 DeltaV=PW1-PROPLUS PIC1-1110/PID1/SP.CV Float Continuous Step 5sec Comp=[SlopingBoxCar 2] Max=14400 DeltaV=PW1-PROPLUS PIC1-1120/AO1/READBACK.CV Float Continuous Automatic 1sec Comp=[SlopingBoxCar 0.1] Max=28800 DeltaV=PW1-PROPLUS PIC1-1120/PID1/MODE.ACTUAL UnicodeString Continuous Automatic 10sec Comp=[SlopingBoxCar 0.01] Max=14400
This identifies the parameter type: Float, UnicodeString, UnsighedInteger, Enumerated, etc.
It also includes the line formatting and compression information.
The Engineering units and range are not included. If you need these, you will have to extract them from the configuration. Knowing the parameter paths, you can locate the associated scaling parameters from the block structure.
The OPC HDA server of the DVCH does expose the scaling information, but I'm not sure how to programmatically extract that. I'd parse the FHX or use excel add in to read scaling data from run time, because I'm familiar with that. Taking the DVCH Dump or the PHIST.SCR file as your tag input, you can extract the Block path and determine the scaling parameter path for the parameter. AI1 means OUT_SCALE for both OUT and PV parameters. PID1 has PV_SCALE for PV and SP, and OUT_SCALE for OUT. and so on. with this you can read the EU0, EU100 and Units fields for each.
I'm thinking there may be a utility to convert DVCH to Advanced Historian, which is really a PI historian. I thought this was available to migrate DVCH users to Advanced Historian. If this exists, migrating the to PI would create a PI database that should contain all the scaling information. But I don't know if this actually exists. I could not find it on our system, but it may be on the installation media, which I don't have handy. Check on Guardian web site if a KBA exists that might instruct you on how to do this.
Andre Dicaire