Recent Control & Safety Systems Discussions
Similar Posts
Scaling logic in 0-100 to 0-4700 in Calc Block?
Updating External Reference Path via String in Calc Block
Changing PCS modules and Functional Blocks to SIS modules and Functional Blocks
MOV Logic via DC function block
Use STATUS parameter of I/O cards in Calc Block
Share

Change the Engineering Unit of a SCALE parameter via CALC block or Function Block

Hi,

In DeltaV I'm trying to change the Engineering Units of the OUT_SCALE parameter of an instance of the C_AI_SOFT130 composite via CALC block.

In the CALC block I've tried the following lines but none of them seems to work:

'^/AI1/OUT_SCALE.UNITS' := 1607;

or 

'^/AI1/OUT_SCALE.UNITS' := "cm";

Do you know if this is at all possible?

Thank you for your help

Davide
  • Davide

    In reply to Matt Stoner:

    Hi Matt,
    thanks again for your help.
    My colleague Neil was able to find a solution to this problem and I want to share it with the community hoping it might be helpful to others;

    It seems that for some reason the statement '^/AI1/OUT_SCALE.UNITS' := 1088; doesn't work;

    What worked was:
    1. In the CM, add an internal parameter of type Floating Point (in our case called KG_ENG_UNIT), and with a value of 1088
    2. In the CALC block re-write the statement as '^/AI1/OUT_SCALE.UNITS' := '^/KG_ENG_UNIT.CV';

    With this new statement we were able to modify the EU of the parameter '^/AI1/OUT_SCALE.UNITS' without having to take the CM OOS.

    (Maybe with the statement '^/AI1/OUT_SCALE.UNITS' := 1088 the CALC block was passing the value as a 32-bit Integer whereas the statement := '^/KG_ENG_UNIT.CV' forces it to pass it as a Floating point? Not sure about it)
  • Davide

    In reply to Matt Stoner:

    Hi Matt,
    yes, using '^/AI1/OUT_SCALE.UNITS' := 1088 in the CALC block doesn't work. What worked was to use '^/AI1/OUT_SCALE.UNITS' := '^/KG_ENG_UNIT.CV'; (where KG_ENG_UNIT is a floating point internal parameter set to 1088).

    Thanks for noticing the error with "l" and "lb".

This is the official online community site of the Emerson Global Users Exchange, a forum for the free exchange of non-proprietary information among the global user community of all Emerson Automation Solution's products and services. Our goal is to improve the efficiency and use of automation systems and solutions employed at members’ facilities by sharing our knowledge, experiences, and application information.

User Groups | World Areas | Community Guidelines | Legal Information | Privacy Policy | Contact Community Manager

Website translation provided by Website Translator

© 2015-2022 Emerson Global Users Exchange. All rights reserved.