Limiting the write tag values like in PID

[arunagiri]

Hi,

I am trying to write the values to the manipulating variable (Final Control Element) like control valves. I want to define low/high limit values to the same tag.

Example:
I wanted to write a value to the tag valve position=22
Low Limit of valve=20
High Limit of valve = 30

when I write valve position=35 for example
It should be sent 30 since it is a High Limit

when I write valve position=15 for example
It should be sent 20 since it is a Low Limit

• This topic was modified 2 years ago by arunagiri.

[Mikhail]

Hi,

You should add a formula in the Formulas table to change a command value if it is out of limits. For example:

public double FixVal(double x)
{
  if (x < 20)
    return 20;
  else if (x > 30)
    return 30;
  else
    return x;
}

Then use the formula in the output channel: FixVal(CmdVal)

• This reply was modified 2 years ago by Mikhail.

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