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<DIV dir=ltr align=left><SPAN lang=en-us><FONT face=Arial size=2>I'm looking for
data pertaining to the subject. I found information on motor efficiencies
at various loads, such as from the MotorMaster database and a couple of research
papers. However, I haven't found clear information on motor efficiencies
when driven by VFDs. Here are the types of information that could be
useful:</FONT></SPAN></DIV>
<P><SPAN lang=en-us><FONT face=Arial size=2>Efficiency vs. load at constant
speed (have that for non-VFD applications)</FONT></SPAN> <BR><SPAN
lang=en-us><FONT face=Arial size=2>Efficiency vs. speed at constant
load</FONT></SPAN> </P>
<P><SPAN lang=en-us><FONT face=Arial size=2>I'm also aware that VFDs can be
setup different ways, but I don't know much about this. I suspect that how
the volts per Hz varies impacts the motor efficiency, so that type of
information would also be valuable.</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial size=2>Or are VFD setups for HVAC
applications inconsistent, so it is hard to generalize?</FONT></SPAN> </P>
<P><SPAN lang=en-us><FONT face=Arial size=2>I am seeking this information
because I am working on some spreadsheet applications for the CEC (that will be
available to everyone) for estimating savings for changes to variable-flow
systems (change to pressure setpoints, resets, etc.)</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial size=2>Any relevant information would be
helpful. I may not be able to incorporate all the information now, but I'd
like to know (and eventually address!) any shortcomings in my current
applications.</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial size=2>Thanks,</FONT></SPAN> <BR><SPAN
lang=en-us><FONT face=Arial size=2>Bill</FONT></SPAN> </P>
<P><SPAN lang=en-us><FONT face=Verdana size=2>William E. Koran,
P.E.</FONT></SPAN> <BR><SPAN lang=en-us><FONT face=Verdana size=2>Senior Energy
Engineer</FONT></SPAN> <BR><SPAN lang=en-us><FONT face="Arial Unicode MS"
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face="Arial Unicode MS" color=#0000ff>I</FONT></SPAN> <BR><SPAN lang=en-us><FONT
face=Verdana size=2>Portland Energy Conservation Inc.</FONT></SPAN> <BR><SPAN
lang=en-us><FONT face=Verdana size=2>1400 SW 5th Avenue, Suite 700</FONT></SPAN>
<BR><SPAN lang=en-us><FONT face=Verdana size=2>Portland, Oregon
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