PID controller to control temperature

[plssendhelp1506]

Hello guys, just to check if I were to include linearized feedback specifically the I=V^2/R  formula here, I can just use the feedback node right? 

-Emma 

[GerdW]

Hi Emma,

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@plssendhelp1506 wrote:

if I were to include linearized feedback specifically the I=V^2/R  formula here, I can just use the feedback node right? 

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Just because you want to "include feedback" doesn't mean you need to use a "feedback node"…

Where exactly do you want to place the "I=V²/R" calculation? Why do you think you need a feedback node for this simple calculation (basically only one CompoundArithmetic node)?

[plssendhelp1506]

Hello GerdW,

To answer your question, I am planning to put it after the manipulated variable since that is the '' end '' product of sp and pv and probably set the voltage and achieve resistance and just a little update I have implemented a formula node with the formula R=V^2/I since both current and voltage is the input here inside so that it matches my block diagram...please let me know if there is anything i can improve on or decorate this file ? ..Thanks

Best regards, 

Emma 

[GerdW]

Hi Emma,

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@plssendhelp1506 wrote:

please let me know if there is anything i can improve on or decorate this file ?

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• Use better control labels, "numeric"/"numeric2" don't reflect anything about "V" or "R"…
• Apparently your formula is more than just "V²/I" so make the formula node larger to show the whole formula! (Code documentation and readability!)
• Why do you need a formula node for such simple calculations?
• What's the sense of implementing the formula node when the result of the calculation isn't used in the loop and isn't even visible in your screenshot?
• Again you attached a VI created in LV2024, even though you should know by now we prefer older LabVIEW versions. (I still prefer LV2019.)

[plssendhelp1506]

Hello GerdW 

So sorry, over here is the code. 

I was thinking it might be difficult if I were to use Compoundarithmetic node, since it only has ADD and MULTIPLY function...

With regards,

Emma 

[GerdW]

Hi Emma,

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@plssendhelp1506 wrote:

I was thinking it might be difficult if I were to use Compoundarithmetic node, since it only has ADD and MULTIPLY function...

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Wrong, it also knows how to subtract and divide! Read the f***ing help!

No formula node needed:

Out of curiosity: how do you determine resistance by multiplying voltage and current? Mr. Ohm declared something different…

[plssendhelp1506]

Hi GerdW,

Tks !

The second sentence is just a false condition that i made up......coz i mean it will be possible for current and voltage to reach 0...unless you turn the supply off

Regards,

Emma 

[GerdW]

Hi Emma,

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@plssendhelp1506 wrote:

The second sentence is just a false condition that i made up

coz i mean it will be possible for current and voltage to reach 0...unless you turn the supply off

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What is the result of the condition when I=0? What will be the result of the comparison function in this case?

You need to evaluate your code much better:

What do you expect for "x<=0" indicator when running this small code?