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Modbus TCP/IP interface to PLC package

Dears,

We have serial interface from a package sending the modbus data to DeltaV. ( Modbus TCP/IP interface)

The package is sending me a mixed of signed and unsigned 16 bits integers values in contiguous registers.

Can we  implement them in DeltaV by creating the same  'Dataset' of 16 bit signed integers for all values?

the mapping can not be change on package vendor side.

any advise?

Thanks for your time taken to answer.

Rodrigue

Rodrigue

• 14 Jan 2021 11:35 PM
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3 Replies

• Lun.Raznik

  

  • 14 Jan 2021 11:43 PM

  On top of my head, DeltaV does not care if you have multiple datasets pointing the same register. Of course DST count will increase but if this is for dislay it will be SCADA tag only.

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• Andre Dicaire

  

  • 15 Jan 2021 1:48 AM

  In reply to Lun.Raznik:

  Lun is correct. Using a second Dataset avoids having to convert values in a DeltaV module. The cost of an additional DST would likely be less than the engineering hours for developing the conversion logic and testing. But you have to map the right registers.
  
  Converting a signed Integer to unsigned integer is not that complicate though. And once you've solved this for one, it's a cut and paste exercise. by doing that, you have one register to worry about. Either way would work.

  Andre Dicaire

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• Rodrigue

  

  • 16 Jan 2021 12:08 AM

  Ok Noted. Thanks for your quick reply !

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