Dynamic Scaling for Tags?

Ignition
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1

A SCADA in development is designed to pull data off of an OIT that provides dynamic decimal point placement and dynamic scaling for a limited number of tags. We've been able to achieve the dynamic decimal points using expressions, but the scaling seems more complicated. The only place I can see to control tag scaling is on the tag itself, where no bindings exist. Is there a work around, or some information I may be missing? I am not seeing anything in the help manual or forum, so any ideas would be appreciated!

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If you're already using an expression binding you should be able to do your scaling manually in there. Hopefully you've made those tags as part of a UDT. Ideally you would have some parameters to the UDT that would determine the scaling.

3

Technically, this is scaling. You're just always using multiples of 10.

An expression such as this would do the trick. (Linear Scaling):

{originalValue} * ({scaledMax} - {scaledMin}) / ({inputMax} - {inputMin}) + {scaledMin} - ({inputMin} * ({scaledMax} - {scaledMin}) / ({inputMax} - {inputMin}))

Alternatively, you can use system.tag.writeBlocking() to write to the scaling parameters of a tag:

#assuming a Linear Scaled Mode
tagPaths = ["path/to/your/tag.scaledLow","path/to/your/tag.scaledHigh"]
system.tag.writeBlocking(tagPatsh,[0,100])
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