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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Your option is to request 20 data points from the chiller manufacturer, for various temperatures and loads, then let eQuest curve fit that data, so that you
have custom performance curves which represent the VFD operation.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">You could use more data than 20 points and do the curve fits yourself in Excel, and then transfer the coefficients back to eQuest. If you research curve fits
on this forum, there are some excellent posts covering this.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">I think 20 points to represent chiller performance is adequate.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">My experience is that if a firm has a good relationship with chiller vendors (i.e. works on several projects with chillers), the chiller vendors should work
with you to provide the requested data. The chiller vendors will want their chillers shown in the best possible light with regards to energy savings, LEED, etc. The best way to do that is via custom performance curves which more accurately reflect chiller
performance.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hope this helps.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;font-family:"Calibri","sans-serif";color:#339966"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#339966">JAH<o:p></o:p></span></b></p>
<p class="MsoNormal"><b><span style="font-size:8.0pt;font-family:"Calibri","sans-serif";color:#339966"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><i><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#339966">James A. Hess, PE, CEM, BEMP</span></i></b><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><br>
Energy Engineer<br>
TME, Inc.<br>
Little Rock, AR<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Mobile: (501) 351-4667<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> equest-users-bounces@lists.onebuilding.org [mailto:equest-users-bounces@lists.onebuilding.org]
<b>On Behalf Of </b>Sambhav Tiwari<br>
<b>Sent:</b> Wednesday, May 08, 2013 7:32 AM<br>
<b>To:</b> equest-users<br>
<b>Subject:</b> [Equest-users] VFD in chillers<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi Equesters,<o:p></o:p></p>
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<p class="MsoNormal"> I have one building where the screw chillers have VFD control but the provision of doing this is not available in software.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Kindly let me know how can i claim the saving.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Thanks<o:p></o:p></p>
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<p class="MsoNormal">Sambhav Tiwari<o:p></o:p></p>
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