https://forge.codesys.com/forge/talk/Engineering/thread/b2cc07c91c/2022-02-24T19:55:59.956000ZRecent posts to Understanding PID Function and Transfering a PID Function to Codesys2022-02-24T19:55:59.956000Z2022-02-24T19:55:59.956000ZLee23https://forge.codesys.com/u/jaedenlee/https://forge.codesys.com6f5c7433b37eb0fb7cddfe919e778587cde99455

<div class="markdown_content"><p>Hello All,</p> <p>I am new to the industry of automation and I could use some advice and clarification on the subject of PIDs. I am using a Groov Epic Proccessor from Opto22 with Codesys installed, and am just transfering over a PID from a previous PAC Control Basic PID, to work on a fan to help regulate temperature of a machine. </p> <p>Currently when I try to build a normal PID function block an error pops up saying that the PID is not defined (<em>Figure 1 &amp; 2</em>), so I subsituted the codesys PID with the OSCAT_BASIC.CTRL_PID (<em>Figure 3</em>) however I am uncertain if this is a suitable replacement or I am doing something wrong. </p> <p>At the same time I am having some difficulties transfering the PID and determining the what can and cannot be transfered over from the PAC Control Basic PID to Codesys. I have listed some of the values of the Oscat function below and what I believe they are connected to however I will admit I may have gotten them wrong and am uncertain of others as I am still a novice.</p> <p>I have also attached a PNG (<em>Figure 4</em>) of the list of settings used in the PAC Control that Im transfering over, I am still unsure of what some of them do as I am reading into them.</p> <p>The Manual that is being referenced is this one: <a href="http://documents.opto22.com/1641_OptoTutorial_SNAP_PAC_PID.pdf" rel="nofollow">http://documents.opto22.com/1641_OptoTutorial_SNAP_PAC_PID.pdf</a></p> <table> <thead> <tr> <th>Codesys Oscat_Basic.CTRL_PID</th> <th>Purpose</th> </tr> </thead> <tbody> <tr> <td>ACT</td> <td>Actual</td> </tr> <tr> <td>SET</td> <td>Setpoint</td> </tr> <tr> <td>SUP</td> <td>(UNSURE)</td> </tr> <tr> <td>OFS</td> <td>Offset</td> </tr> <tr> <td>M_I</td> <td>(UNSURE)</td> </tr> <tr> <td>Manual</td> <td>Manual Switch</td> </tr> <tr> <td>Reset</td> <td>Reset Switch</td> </tr> <tr> <td>KP</td> <td>KP (Proportional)</td> </tr> <tr> <td>TN</td> <td>TN (Integral)</td> </tr> <tr> <td>TV</td> <td>TV (Derivative)</td> </tr> <tr> <td>LL</td> <td>(UNSURE)</td> </tr> <tr> <td>LH</td> <td>(UNSURE)</td> </tr> <tr> <td>Y</td> <td>Control Output?</td> </tr> <tr> <td>DIFF</td> <td>(UNSURE)</td> </tr> <tr> <td>LIM</td> <td>Limits</td> </tr> </tbody> </table> <p>I have also attached a PNG Showing the previous HMI (<em>Figure 5</em>) that is used in PAC Display if that helps clarify anthing. I am thinking I may need to trim and take away some of the variables in my codesys HMI as some of them might not useless in Codesys.</p> <p>Thank you for your time, any feedback or advice is greatly appreciated.</p></div>