Modicon M241 Logic Builder - Custom FB Output issues.

[Corm8873]

Hello,

I just wanted to thank in advance for taking the time to read and help if possible.

I'm currently working on a project creating the Logic for a Modicon M241 PLC. The site will be inputting values from other PLCs. To scale the values to the appropriate range I wrote a custom scaling function block. I've added to the post the logic for my custom function block.

My question is why is my output variable staying at 0. According to the logic the equation should equal 60. But no matter values I input my output variable is always equal to 0. See image below.

 

[drbitboy]

Try ((A * C) / B) + rPARMScaleMin

 

[goghie]

Because it is INT, and you are dividing 600/1000 (A/B), and that is 0. Them you are multiplying 0 with C, and again it is zero. Then you are adding rPARMScaleMin (again 0).

 

[drbitboy]

Try ((A * C) / B) + rPARMScaleMin

Better: (((A * C) + (B/2)) / B) + rPARMScaleMin