<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">This mailing list is being discontinued and in its place we are implementing a user forum. Please post your questions on the new forum in the future; www.trnsys.com/community<div><br></div><div>But to answer your question, the example and the documentation are both consistent. Start with the tank half full and the controller off. When the tank indicates it is empty (state = -1) the controller will start filling the tank</div><div><br></div><div>Controller turns ON when input 1 - input 2 > upper deadband </div><div><br></div><div>0 - -1 = 1 which is greater than the upper deadband of 0.9</div><div><br></div><div>When the tank indicates it is full (state = 1) the controller will stop filling the tank:</div><div><br></div><div>0 - 1 = -1 which is less than the lower deadband of -0.9</div><div><br></div><div>You should connect the model to itself so the model can calculate the previous state of the controller correctly. In some cases you may want the controller to calculate its signal based on the operation of a different controller - in that case you would connect the input of the controller to the status of the other controller (rare).</div><div><br></div><div>Jeff/TESS</div><div><br></div><div><br></div><div><br id="lineBreakAtBeginningOfSignature"><div dir="ltr">Sent from my iPhone</div><div dir="ltr"><br><blockquote type="cite">On Jun 18, 2024, at 8:43 AM, saeid mohammadzadeh via TRNSYS-users <trnsys-users@lists.onebuilding.org> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">Hello everyone, </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">I have a question about the ON/OFF Differential controller in the PVT example in TRNSYS. The tank level indicator is from 1 (full) to -1 (lower) and 0 (in between). </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">In this example, in order to maintain the level in water in the tank, the first value is set to zero; the second value is connected to the level indicator. The upper and lower dead bands are 0.9 and -0.9, respectively. </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">Can somebody please explain this to me? Since it is against what is explained about dead bands in the software. (copied below)</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">"The controller is ON if it was previously ON and Th (Input 1) minus T (Input 2) is greater than the lower dead band. Otherwise the controller is OFF.<br>The controller is ON if it was previously OFF and Th (Input 1) minus Tl (Input 2) is greater than the upper dead band. Otherwise the controller is OFF."<br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">I have another question, why we should connect ON/OFF Differential controller to itself again?</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="color:rgb(0,0,0)"><i style="font-size:12.8px"><font color="#000000" size="2"><i><font color="#000000" face="arial, helvetica, sans-serif">Best Regards</font></i></font></i><br></div><div style="color:rgb(0,0,0)"><i><font size="2" face="arial, helvetica, sans-serif">Saeid Bina, Dr. (Eng.)</font></i></div><div style="color:rgb(0,0,0)"><i style="font-size:12.8px;color:rgb(34,34,34)"><font color="#000000" face="times new roman, new york, times, serif" size="2"><i><font color="#000000" face="arial, helvetica, sans-serif" size="3">-------------------------------------------------</font></i></font></i></div><div style="color:rgb(0,0,0);font-family:HelveticaNeue,"Helvetica Neue",Helvetica,Arial,"Lucida Grande",sans-serif"><font color="#000000" face="times new roman, new york, times, serif" size="2"><div align="left"><font face="arial, helvetica, sans-serif" size="3" style="font-size:16px"><font color="#000000" face="times new roman, new york, times, serif" size="2"><div align="left"><em><font face="times new roman,serif">Akita <var></var>University</font></em><br></div></font></font><font face="arial, helvetica, sans-serif"><font color="#000000" face="times new roman, new york, times, serif" size="2"><div align="left"><span style="font-family:"Times New Roman",serif"><i>Graduate
school of International Resource Sciences</i></span><font face="times new roman,serif"><em>.<br>1-1 Tegata gakuen-machi, Akita 010-8502, Japan</em></font></div></font></font></div><div align="left" style="font-size:16px"></div></font><font color="#000000" face="times new roman, new york, times, serif" size="2" style="font-size:16px"><div align="left"><div style="font-family:HelveticaNeue,"Helvetica Neue",Helvetica,Arial,"Lucida Grande",sans-serif;font-size:16px"><i><font color="#000000" face="times new roman, new york, times, serif" size="2"><i><font color="#000000" face="arial, helvetica, sans-serif" size="3">-------------------------------------------------<br><br><br></font></i></font></i></div><div style="font-family:HelveticaNeue,"Helvetica Neue",Helvetica,Arial,"Lucida Grande",sans-serif;font-size:16px"><font color="#000000" face="times new roman, new york, times, serif" size="2"><div align="left"><font face="arial, helvetica, sans-serif" size="3"><font color="#000000" face="times new roman, new york, times, serif" size="2"></font></font></div></font></div></div></font></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
<div><Screenshot 2024-06-18 134829.png></div><span>_______________________________________________</span><br><span>TRNSYS-users mailing list</span><br><span>TRNSYS-users@lists.onebuilding.org</span><br><span>http://lists.onebuilding.org/listinfo.cgi/trnsys-users-onebuilding.org</span><br></div></blockquote></div></body></html>