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<div class=Section1>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I’m also on board that engaging the vendor reps and mechanical
engineers responsible for specification “shouldn’t” be a bother, and that we
energy modelers “should” be welcomed as part of the design process. That said…<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 includes mechanical designers and vendor reps who
are… perturbed… when you start asking questions about variables they aren’t
used to thinking around. Some will get unnecessarily defensive, and I think I
have an idea why.<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'>The most important quality in a great energy modeler is not the
ability to use his/her tools and crunch the numbers (that’s more like a
pre-req), but being an effective communicator/teacher of inputs and results to
a wide range of audiences. <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'>It’s deceptively easy to get bogged down when working with
others for something like custom performance curves, and inquiries / suggestions
of the best intentions can come across as <u>challenging another’s thought
process</u>. To put it nicely, some will take that very personally, so it’s a
delicate line to walk when having these conversations. Those of us who aren’t
as advanced in experience (old) in this industry have the extra hurdle of not
seeming pretentious/ignorant while trying to do our jobs!<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'>Thanks again to everyone contributing… I’m learning a heck of a
lot at a fast pace with you all!<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'>~Nick<o:p></o:p></span></p>
<div>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><img width=119 height=37 id="Picture_x0020_1"
src="cid:image001.jpg@01CB7B67.50D00890" alt="cid:489575314@22072009-0ABB"></span><b><span
style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p> </o:p></span></b></p>
<p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";
color:#2D4D5E'>NICK CATON, E.I.T.</span></b><b><span style='font-family:"Stylus BT","sans-serif";
color:#2D4D5E'><o:p></o:p></span></b></p>
<p class=MsoNormal><span style='font-size:7.5pt;font-family:"Calibri","sans-serif";
color:#CC9900'>PROJECT ENGINEER</span><span style='font-size:7.5pt;color:#CC9900'><o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";
color:#2D4D5E'>25501 west valley parkway<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";
color:#2D4D5E'>olathe ks 66061<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";
color:#2D4D5E'>direct 913 344.0036<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";
color:#2D4D5E'>fax 913 345.0617<o:p></o:p></span></p>
<p class=MsoNormal><i><span style='font-size:10.0pt;font-family:"Calibri","sans-serif";
color:#2D4D5E'>Check out our new web-site @ </span></i><span style='font-size:
11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><a
href="www.smithboucher.com" title="blocked::www.smithboucher.com"><span
style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:blue'> </span></u><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p></o:p></span></p>
</div>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<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>John T.
Forester<br>
<b>Sent:</b> Wednesday, November 03, 2010 1:57 PM<br>
<b>To:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Equest-users] Chiller Curves (oh boy!)<o:p></o:p></span></p>
</div>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'>Oh boy! - It seems that there is some confusion with my thoughts on
Nick’s chiller curve posts from earlier.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'>My experience has been that catalog and online data for water
chilling packages provides typical ARI Standard 550/590 data. This data
is NOT sufficient to create custom curves in eQuest unless each hour’s
operating points never stray off of these curves (not likely). This is
why I suggest working with the Mechanical Engineer and the Vendor. As a
design/support community, I don’t believe this approach is a “bother” to either
one of these team members. The approach of an integrated design process
has its merits and the participation of the energy modeler is welcome
throughout the design process. I also recognize the time it takes vendors
to provide this data. Therefore, suggesting that, unless it is expected
that the chiller will be operating above its design point, this added data is
not necessary for accurate custom curves.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'>Also, I am not suggesting that equipment is selected without
sufficient capacity to serve the calculated loads of a building/process.
I was simply stating possible cases where performance information for a chiller
between design and maximum capacities may be needed.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'>John<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Arial","sans-serif";
color:navy'><o:p> </o:p></span></p>
<div>
<p class=MsoNormal><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:gray'>John T. Forester, P.E., LEED AP, Mechanical Design Engineer </span><strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:#0000A0'>I BVH
Integrated Services I</span></strong><strong><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:black'> </span></strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>617.658.9008
tel </span><strong><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'>I</span></strong><strong><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:gray'> </span></strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>617.244.3753
fax</span><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'> <strong><span style='font-family:"Arial","sans-serif"'>I</span></strong></span><strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'> </span></strong><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>One Gateway
Center Suite 506, Newton MA 02458 </span><strong><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:#0000A0'>I <a href="http://www.bvhis.com">www.bvhis.com</a> I
Hartford ● New Haven ● Boston</span></strong><span style='color:gray'><o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal align=center style='text-align:center'><hr size=2
width="100%" align=center tabindex=-1> <o:p></o:p></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"'> Paul Diglio
[mailto:paul.diglio@sbcglobal.net] <br>
<b>Sent:</b> Wednesday, November 03, 2010 2:18 PM<br>
<b>To:</b> Carol Gardner; John T. Forester<br>
<b>Cc:</b> equest-users@lists.onebuilding.org<br>
<b>Subject:</b> Re: [Equest-users] Chiller Curves (oh boy!)</span><o:p></o:p></p>
</div>
<p class=MsoNormal><o:p> </o:p></p>
<div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt'>John:<br>
<br>
In my opinion one needs to get the chiller modeled by the factory as the catalogs
do not contain nearly enough information.<br>
<br>
See attached spreadsheet. The top portion was provided by Trane. It
models this chiller at Standard, Maximum and Minimum condenser water
flows. I performed the calculations in the red border.<br>
<br>
I needed to model this in Excel for a utility incentive. I was
implementing variable condenser water flow. The kW/Ton increases using a
variable flow sequence.<br>
<br>
My total kWh savings for varying the speed of the condenser pumps was
approximately 250,000. The chiller consumed approximately 50,000 kWh more
with minimum condenser water flow.<br>
<br>
Trane modeled this project several times for me, they had a self-interest
because I was contracting them to perform some board upgrades as part of the
energy efficiency project.<br>
<br>
Paul Diglio<o:p></o:p></span></p>
</div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt'><o:p> </o:p></span></p>
<div>
<div class=MsoNormal align=center style='text-align:center'><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>
<hr size=1 width="100%" align=center>
</span></div>
<p class=MsoNormal style='margin-bottom:12.0pt'><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"'> Carol Gardner <cmg750@gmail.com><br>
<b>To:</b> John T. Forester <JohnTF@bvhis.com><br>
<b>Cc:</b> "equest-users@lists.onebuilding.org" <equest-users@lists.onebuilding.org><br>
<b>Sent:</b> Wed, November 3, 2010 1:54:35 PM<br>
<b>Subject:</b> Re: [Equest-users] Chiller Curves (oh boy!)<br>
</span><br>
I agree with you, John, but have a couple of other thoughts to add. The first
is I have not met a mechanical engineer that does not select a chiller that is
capable of supplying all loads. In fact, they generally oversize a bit to
accommodate possible future loads. The only piece of equipment I have ever seen
selected at over 100% was a VRV system and that is because they actually work
better at 120% loading. The second is that you can generally get a catalog from
a manufacturer to have on your shelf that has technical information like how
the chiller unloads based on temperatures and what the efficiency is at part
load so you can look up the chiller you need info for and not need to bother
the ME or the vendor. If you can't get/don't want a hard copy, most of this
info is on line, just look for technical specifications.<br>
<br>
Best,<br>
<br>
Carol<o:p></o:p></p>
<div>
<p class=MsoNormal>On Wed, Nov 3, 2010 at 9:48 AM, John T. Forester <<a
href="mailto:JohnTF@bvhis.com" target="_blank">JohnTF@bvhis.com</a>> wrote:<o:p></o:p></p>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>Nick,</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>I think
you’re on the right track. Below are some of my thoughts on your
conclusions. I hope the modeling community will set me straight if I’m
wrong here.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<ol start=1 type=1>
<li class=MsoNormal style='color:navy;mso-margin-top-alt:auto;mso-margin-bottom-alt:
auto;mso-list:l1 level1 lfo3'><span style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Getting multiple performance runs from vendors that
show part-load performance independent of the CW and CHW temps can often
be challenging. Adding the “maximum capability” task to that for
each of the conditions requires a pretty detailed understanding of the selection
software. I’d say if you can get PLR data for 3-4 different CHW
temps while holding the CW temps constant at 85, 75, 65 (and sometimes
lower) – you’re ahead of most modelers. Working with the Mechanical
Design Engineer and the vendor together has been successful for me in the
past.</span><o:p></o:p></li>
<li class=MsoNormal style='color:navy;mso-margin-top-alt:auto;mso-margin-bottom-alt:
auto;mso-list:l1 level1 lfo3'><span style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Defining the chiller capabilities at the “maximum”
may only come into play if you expect your model to overload the chiller
above the specified design capacity (I’m thinking building additions or
process loads). At this point, this data (or knowing what the default
eQuest curves do in that range) would be useful. Depending on your
project, the time spent on developing curves for PLR >1.0 may not be
justified.</span><o:p></o:p></li>
<li class=MsoNormal style='color:navy;mso-margin-top-alt:auto;mso-margin-bottom-alt:
auto;mso-list:l1 level1 lfo3'><span style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>If you don’t have “max” data and don’t want eQuest
to assume performance at a part-load ratio >1.0, you can set the
DESIGN-PLR to 1.0.</span><o:p></o:p></li>
<li class=MsoNormal style='color:navy;mso-margin-top-alt:auto;mso-margin-bottom-alt:
auto;mso-list:l1 level1 lfo3'><span style='font-size:10.0pt;font-family:
"Arial","sans-serif"'>Either way, you want your curves to be normalized at
whatever condition you specify (Design or Rated) and you want to enter
those values on the Basic Specifications tab.</span><o:p></o:p></li>
</ol>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>John</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>John T.
Forester, P.E., LEED AP, Mechanical Design Engineer </span><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:#0000A0'>I BVH
Integrated Services I</span></b><b><span style='font-size:8.5pt;font-family:
"Arial","sans-serif";color:black'> </span></b><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:gray'>617.658.9008 tel </span><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:#0000A0'>I</span></b><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'> </span></b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>617.244.3753
fax</span><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'> <b>I</b></span><b><span style='font-size:8.5pt;font-family:
"Arial","sans-serif";color:gray'> </span></b><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:gray'>One Gateway Center Suite 506,
Newton MA 02458 </span><b><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'>I <a href="http://www.bvhis.com" target="_blank">www.bvhis.com</a> I
Hartford ● New Haven ● Boston</span></b><o:p></o:p></p>
</div>
</div>
<div>
<p class=MsoNormal align=center style='text-align:center'>size=2
width="100%" align=center tabindex=-1> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><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"'> Nick Caton [mailto:<a
href="mailto:ncaton@smithboucher.com" target="_blank">ncaton@smithboucher.com</a>]
<br>
<b>Sent:</b> Wednesday, November 03, 2010 12:06 PM<br>
<b>To:</b> John T. Forester; <a href="mailto:equest-users@lists.onebuilding.org"
target="_blank">equest-users@lists.onebuilding.org</a><o:p></o:p></span></p>
<div>
<div>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'><br>
<b>Subject:</b> RE: [Equest-users] Chiller Curves (oh boy!)<o:p></o:p></span></p>
</div>
</div>
</div>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>John,</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The
design/max ratio is exactly what I’m discussing below when I say “DESIGN-PLR
ratio,” so we’re definitely in the same ballpark =).</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I’d
like to apply/paraphrase your advice to a few conditions to be sure I’m getting
it correctly: </span><o:p></o:p></p>
<p><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-</span><span
style='font-size:7.5pt;color:#1F497D'>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If we create all 3 custom curves, and normalize each to a point
at maximum (not design) capacity, then the design-to-max ratio (DESIGN-PLR)
should be set to 1.00.</span><o:p></o:p></p>
<p><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-</span><span
style='font-size:7.5pt;color:#1F497D'>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If we create <u>only</u> the part load efficiency curve
(EIR-FPLR or EIR-FPLR&dT), and wish to use the library defaults for EIR-FT
and CAP-FT, then we should normalize this curve’s data points to ARI conditions
(as that’s what the library curves are normalized to, per James’s email – I
think I’ve read this somewhere also), specify an ARI capacity, EIR and
conditions on the basic specifications tab, and enter a DESIGN-PLR of [ARI
capacity/maximum capacity (for the same conditions)].</span><o:p></o:p></p>
<p><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-</span><span
style='font-size:7.5pt;color:#1F497D'>
</span><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If we create all 3 custom curves, and try to normalize each to
either ARI or design conditions, then we should specify capacity, EIR, CHWT,
CWT and condenser GPM corresponding to either the ARI or design conditions of
that normalizing point. In that case, we also specify a DESIGN-PLR using
either the ARI or design capacity divided by the maximum capacity for the same
conditions.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><u><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Profound
(to me) Conclusion</span></u><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>: In <u>No</u> instance should we <u>Ever</u> attempt
creating custom curves and NOT have at least one run from our manufacturer
telling us what the maximum (not design) capacity is for the normalizing
point. This conclusion would only apply to centrifugal chillers only.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Does
this all sound right?</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>~Nick</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>James,
</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Yeah,
if all the part load data you received held the same CHWT and CWT equal, you
might be able to make your part-load curve if it could have been a quadratic
EIR-FPLR curve (like a reciprocating chiller), but not a bi-quadratic
EIR-FPLR&dT (as with my centrifugal VSD chiller). You definitely
could not approach generating custom EIR-FT or CAP-FT curves without varying
condenser and chilled water temps. That exact issue happened to me the
first few times I tried to reign my chiller reps in =). </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>This
time, I convinced my rep to give me multiple part load runs holding the CHWT
constant and varying the CWT incrementally. This let me build the
bi-quadratic EIR-FPLR&dT curve as I had at least three different dT’s
represented in my part load data points. I plotted the 3D curve in excel
to check my work and darned if the generated coefficients seem to be really
accurate =)! It’s currently looking like a bittersweet revelation
however – the library curve for a water-cooled centrifugal VSD chiller (see
attached visualization) seems a LOT more generous (more efficient) at low part
loads than the one I’ve generated which matches my rep’s data… I might
share a visual of my custom curve for comparison once I’m dead-sure it’s
accurate – I’m trying to clarify a few things with my rep right now.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>~Nick</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img
border=0 width=119 height=37 id="_x0000_i1026" src="%20"
alt="cid:489575314@22072009-0ABB"></span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E'> </span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E'>NICK
CATON, E.I.T.</span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:7.5pt;font-family:"Calibri","sans-serif";color:#CC9900'>PROJECT
ENGINEER</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>25501
west valley parkway</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>olathe
ks 66061</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>direct
913 344.0036</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>fax
913 345.0617</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><i><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>Check
out our new web-site @ </span></i><span style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'><a href="http://www.smithboucher.com"
target="_blank" title="blocked::www.smithboucher.com"><span style='font-size:
10.0pt'>www.smithboucher.com</span></a></span><u><span style='font-size:10.0pt;
font-family:"Calibri","sans-serif";color:blue'> </span></u><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<div>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><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"'> John T. Forester [mailto:<a
href="mailto:JohnTF@BVHis.com" target="_blank">JohnTF@BVHis.com</a>] <br>
<b>Sent:</b> Wednesday, November 03, 2010 10:29 AM<br>
<b>To:</b> Nick Caton; <a href="mailto:equest-users@lists.onebuilding.org"
target="_blank">equest-users@lists.onebuilding.org</a><br>
<b>Subject:</b> RE: [Equest-users] Chiller Curves (oh boy!)</span><o:p></o:p></p>
</div>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>Nick,</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>When
defining a centrifugal chiller in eQuest, one of the items on the Basic
Specifications tab under the Design vs. Rated Conditions is a Design/Max Cap
ratio. By default, this is 92% for a water cooled unit. I believe
this gets at the discussion in the help pages that talks about maximum capacity
versus design capacity and how the chiller vendor will spec a piece of
equipment. Typically, vendors don’t often get asked (or provide) what the
“Maximum” capacity of a spec’d unit is. Therefore the performance data
that they provide are at “design conditions.”</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>If you
change the chiller type to a reciprocating chiller, this “Design/Max Cap” ratio
is disabled and the default specified condition changes from “Design
Conditions” to “Rated Conditions.” This suggests that there is little
“extra” capacity when a selection is done for that type of chiller.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>If you do
get “maximum capacity” data and create curves from that data, you will want to
change the Design/Max Cap ratio to 1.0 so eQuest knows that there isn’t any
spare capacity at the chiller. Also if the data points you are using to
normalize your curves are different than the design conditions for your energy
model, you will want to change the “Chiller Specified at” value to “Rated
Conditions” and enter the rated conditions for CHW temp, CW temp and CW gpm/ton
to match your normalized curves.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>Hope this
helps,</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'>John</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Arial","sans-serif";color:navy'> </span><o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>John T.
Forester, P.E., LEED AP, Mechanical Design Engineer </span><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:#0000A0'>I BVH
Integrated Services I</span></b><b><span style='font-size:8.5pt;font-family:
"Arial","sans-serif";color:black'> </span></b><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:gray'>617.658.9008 tel </span><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:#0000A0'>I</span></b><b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'> </span></b><span
style='font-size:8.5pt;font-family:"Arial","sans-serif";color:gray'>617.244.3753
fax</span><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'> <b>I</b></span><b><span style='font-size:8.5pt;font-family:
"Arial","sans-serif";color:gray'> </span></b><span style='font-size:8.5pt;
font-family:"Arial","sans-serif";color:gray'>One Gateway Center Suite 506,
Newton MA 02458 </span><b><span style='font-size:8.5pt;font-family:"Arial","sans-serif";
color:#0000A0'>I <a href="http://www.bvhis.com" target="_blank">www.bvhis.com</a> I
Hartford ● New Haven ● Boston</span></b><o:p></o:p></p>
</div>
<div>
<p class=MsoNormal align=center style='mso-margin-top-alt:auto;mso-margin-bottom-alt:
auto;text-align:center'><hr size=2 width="100%" align=center
tabindex=-1> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><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"'> <a
href="mailto:equest-users-bounces@lists.onebuilding.org" target="_blank">equest-users-bounces@lists.onebuilding.org</a>
[mailto:<a href="mailto:equest-users-bounces@lists.onebuilding.org"
target="_blank">equest-users-bounces@lists.onebuilding.org</a>] <b>On Behalf Of
</b>Nick Caton<br>
<b>Sent:</b> Wednesday, November 03, 2010 11:03 AM<br>
<b>To:</b> Carol Gardner; <a href="mailto:equest-users@lists.onebuilding.org"
target="_blank">equest-users@lists.onebuilding.org</a><br>
<b>Subject:</b> Re: [Equest-users] Chiller Curves (oh boy!)</span><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Thanks
for the response Carol!</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>That
120% load case is what I’m getting at – let me try to explain a little further:</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In
the DOE2 help files, the vocabulary for centrifugal chillers is “design
capacity” and “maximum capacity,” where “design” means the capacity at the
rated or designed conditions (at which you define / specify your chiller), and
“maximum” means the capacity the chiller is really capable of under the same
conditions if it runs balls-out (maximum power to the refrigerant drive).</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The
help file excerpt I copied below with the red line is pretty explicitly telling
us to normalize the part load values to the <u>maximum</u> capacity for
centrifugal chillers. I’ve highlighted a second line for clarity.
The EDR guidelines I linked below are saying you can instead normalize to the <u>design</u>
capacity for the EIR-PLR curve if that’s all your field measurements or
manufacturer rep can provide.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I’m
asking – are both approaches right? </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>My
first and second questions are kinda tied together… How would choosing to
normalize to either the maximum or design conditions affect how we should
handle the DESIGN-PLR ratio, if at all?</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>~Nick.</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img
border=0 width=119 height=37 id="_x0000_i1027" src="%20"
alt="cid:489575314@22072009-0ABB"></span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E'> </span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:11.0pt;font-family:"Stylus BT","sans-serif";color:#2D4D5E'>NICK
CATON, E.I.T.</span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:7.5pt;font-family:"Calibri","sans-serif";color:#CC9900'>PROJECT
ENGINEER</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>25501
west valley parkway</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>olathe
ks 66061</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>direct
913 344.0036</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>fax
913 345.0617</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><i><span
style='font-size:10.0pt;font-family:"Calibri","sans-serif";color:#2D4D5E'>Check
out our new web-site @ </span></i><span style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'><a href="http://www.smithboucher.com"
target="_blank" title="blocked::www.smithboucher.com"><span style='font-size:
10.0pt'>www.smithboucher.com</span></a></span><u><span style='font-size:10.0pt;
font-family:"Calibri","sans-serif";color:blue'> </span></u><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p>
<div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><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"'> Carol Gardner
[mailto:<a href="mailto:cmg750@gmail.com" target="_blank">cmg750@gmail.com</a>]
<br>
<b>Sent:</b> Tuesday, November 02, 2010 10:04 PM<br>
<b>To:</b> Nick Caton<br>
<b>Cc:</b> <a href="mailto:equest-users@lists.onebuilding.org" target="_blank">equest-users@lists.onebuilding.org</a><br>
<b>Subject:</b> Re: [Equest-users] Chiller Curves (oh boy!)</span><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>Let me
take a crack at this. If by design capacity you mean the chiller running at
100% load, you would create the curve(s) by normalizing around your ARI design
conditions i.e. the PLR curve would be 1.0 at this point, call it ARI Cap and
the other points would be 90% Cap/ARI Cap, 80% Cap/ARI Cap, etc. The same would
go for your temp curves. If, however, your chiller is operating at 120%, or
some such other level, I would normalize the curve around the ARI design conditions
of the chiller at 120%. I had to do this for a VRV hp that was selected at the
120% design condition.<br>
<br>
I find this from the DOE2 manual the most helpful:<o:p></o:p></p>
<div style='border-top:solid #999999 1.0pt;border-left:none;border-bottom:solid #999999 1.0pt;
border-right:none;padding:0in 0in 0in 0in'>
<div>
<div>
<p> <o:p></o:p></p>
</div>
</div>
</div>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><a
href="http://volume2dictionary.htm" target="_blank">Volume 2: Dictionary</a>
> <a href="http://hvaccomponents.htm" target="_blank">HVAC Components</a>
> <a href="http://curvefit.htm" target="_blank"><span style='color:white;
background:#316AC5'>CURVE</span>-<span style='color:white;background:#316AC5'>FIT</span></a>
> <a href="http://inputtypedata.htm" target="_blank">INPUT-TYPE = DATA</a><o:p></o:p></p>
</div>
<h5>INDEPENDENT-2<o:p></o:p></h5>
<p>Used for all <span style='color:white;background:#316AC5'>curves</span> having
two independent variables. A list of up to twenty values of the second
independent variable. The number of values should be the same as for DEPENDENT.<o:p></o:p></p>
<p><b><span style='font-family:"Arial","sans-serif"'>Example 1</span></b>:
defining a <span style='color:white;background:#316AC5'>curve</span> by
inputting a set of data points.<o:p></o:p></p>
<p>A packaged system (PZS) has cooling performance significantly different from
that used in the default model. The manufacturer lists the data shown in
Table 46, for cooling capacity, at 2000 cfm design air flow rate, as a function
of outside dry-bulb temperature and entering wet-bulb temperature.<o:p></o:p></p>
<p><a name="12c12a536c514b6a__Ref490744859"></a><a
name="12c12a536c514b6a__Ref490744804"></a>Table 46 Cooling capacity
(kBtu/hr) vs. temperature<o:p></o:p></p>
<div style='margin-top:2.0pt;margin-bottom:2.0pt'>
<div align=center>
<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0
style='border-collapse:collapse'>
<tr>
<td width=96 rowspan=2 valign=top style='width:1.0in;border:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='margin-top:0in;text-align:center'><b>Outside<br>
Dry-bulb</b><o:p></o:p></p>
</td>
<td width=288 colspan=3 valign=top style='width:3.0in;border-top:solid windowtext 1.0pt;
border-left:none;border-bottom:none;border-right:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>Entering Wet-bulb</b><o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>72F</b><o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>67F</b><o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:none;
border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>62F</b><o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>85F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>69<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>65<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>60<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>95F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>68<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>63 (ARI)<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>57<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>105F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>65<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>60<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>53<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>115F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>62<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>55<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:none;
border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:
center'>49<o:p></o:p></p>
</td>
</tr>
</table>
</div>
</div>
<p> <o:p></o:p></p>
<p>In this example the independent variables are the entering wet-bulb
temperature and the outside dry-bulb temperature. Because there are two
independent variables and they have units of temperature, we input a <span
style='color:white;background:#316AC5'>curve</span> of TYPE BI-QUADRATIC-T
using the given data points. The dependent variable is not the cooling capacity
listed in the table but rather the cooling capacity divided by the cooling
capacity at the ARI rating point (95 F outside dry-bulb and 67 F entering
wet-bulb). In other words, the capacities should be normalized to the ARI
rating point., as shown in Table 47<o:p></o:p></p>
<p><a name="12c12a536c514b6a__Ref490745029">Table </a>47 Normalized
capacity vs. temperature<o:p></o:p></p>
<div style='margin-top:2.0pt;margin-bottom:2.0pt'>
<div align=center>
<table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0
style='border-collapse:collapse'>
<tr>
<td width=96 rowspan=2 valign=top style='width:1.0in;border:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='margin-top:0in;text-align:center'><b>Outside<br>
Dry-bulb</b><o:p></o:p></p>
</td>
<td width=288 colspan=3 valign=top style='width:3.0in;border-top:solid windowtext 1.0pt;
border-left:none;border-bottom:none;border-right:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>Entering Wet-bulb</b><o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>72F</b><o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:
0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>67F</b><o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:none;
border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
background:aqua;padding:0in 5.4pt 0in 5.4pt;background-position-x:0%;
background-position-y:0%;background-attachment:scroll'>
<p align=center style='text-align:center'><b>62F</b><o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>85F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>1.095<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>1.032<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.952<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>95F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>1.079<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>1.0 (ARI)<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.905<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:solid windowtext 1.0pt;
border-bottom:none;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>105F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>1.032<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.952<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.841<o:p></o:p></p>
</td>
</tr>
<tr>
<td width=96 valign=top style='width:1.0in;border:solid windowtext 1.0pt;
border-top:none;padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>115F<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.984<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border:none;border-bottom:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='text-align:center'>0.873<o:p></o:p></p>
</td>
<td width=96 valign=top style='width:1.0in;border-top:none;border-left:none;
border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;
padding:0in 5.4pt 0in 5.4pt'>
<p align=center style='margin-bottom:0in;margin-bottom:.0001pt;text-align:
center'>0.778<o:p></o:p></p>
</td>
</tr>
</table>
</div>
</div>
<p> <o:p></o:p></p>
<p>The <span style='color:white;background:#316AC5'>CURVE</span>-<span
style='color:white;background:#316AC5'>FIT</span> input will look like the
following:<o:p></o:p></p>
<p>CAP-<span style='color:white;background:#316AC5'>CURVE</span>-1 = <span
style='color:white;background:#316AC5'>CURVE</span>-<span style='color:white;
background:#316AC5'>FIT</span><br>
TYPE
= BI-QUADRATIC-T<br>
INPUT-TYPE = DATA<br>
DEPENDENT =
(1.000,1.079,0.905,1.032,0.952,0.841,<br>
0.984,0.873,0.778,1.095,1.032,0.952) ..<br>
IN-TEMP1 =
( 67, 72, 62, 72,
67, 62,<br>
72, 67, 62,
72, 67, 62) ..<br>
IN-TEMP2 =
( 95, 95, 95, 105, 105,
105,<br>
115, 115, 115,
85 85, 85) ..<o:p></o:p></p>
<p><b><span style='font-family:"Arial","sans-serif"'>Example 2:</span></b>
Defining a <span style='color:white;background:#316AC5'>curve</span> by
inputting coefficients<o:p></o:p></p>
<p>We want a furnace to have a constant efficiency as a function of part load.
To do this we must replace the default FURNACE-HIR-FPLR with a <span
style='color:white;background:#316AC5'>curve</span> that will give a constant
efficiency. The <span style='color:white;background:#316AC5'>curve</span> TYPE
is QUADRATIC in the part load ratio (PLR). PLR correction <span
style='color:white;background:#316AC5'>curves</span> are always multiplied by
the unit capacity, not the load, to obtain the energy (fuel or electricity)
use. Thus the <span style='color:white;background:#316AC5'>curve</span> we want
is: 0.0 + 1.0*PLR + 0.0*PLR*PLR. The input will look like:<o:p></o:p></p>
<p>New-Furnace-HIR-fPLR = <span style='color:white;background:#316AC5'>CURVE</span>-<span
style='color:white;background:#316AC5'>FIT</span><br>
TYPE
= QUADRATIC<br>
INPUT-TYPE = COEFFICIENTS<br>
COEFFICIENTS = (0.0,1.0,0.0) ..<o:p></o:p></p>
<p>Then in the SYSTEM command we include:<o:p></o:p></p>
<p> FURNACE-HIR-FPLR = New-Furnace-HIR-fPLR<o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'> <o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On
Tue, Nov 2, 2010 at 3:21 PM, Nick Caton <<a
href="mailto:ncaton@smithboucher.com" target="_blank">ncaton@smithboucher.com</a>>
wrote:<o:p></o:p></p>
<div>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'>Hi everyone!</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'>I think I have <u>finally</u> wrapped my mind completely
around custom chiller performance curves for a centrifugal VSD chiller.
I’ve got a few specific questions now that I’m on the other side of the fence:</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'> </span><o:p></o:p></p>
<p><span style='color:#1F497D'>1.</span><span style='font-size:7.0pt;
color:#1F497D'> </span><span
style='color:#1F497D'>Is it necessary for the data points of a part load
efficiency curve (EIR-FPLR&dT in my case) to originate from data with a 1.0
(100%) PLR ratio corresponding to a maximum vs. a design load capacity?
From what I gather in <a
href="http://www.energydesignresources.com/Portals/0/documents/DesignGuidelines/EDR_DesignGuidelines_%20HVAC_Simulation.pdf"
target="_blank">the EDR reference</a> (re: “Method 2” on PDF page 32/65), this
curve can be generated using part-load readings assuming a <u>design</u>
capacity at the 100% loading mark… but the DOE2 help entry for “EIR-FPLR” seems
to suggest otherwise (copied below – see highlighted line).</span><o:p></o:p></p>
<p><span style='color:#1F497D'>2.</span><span style='font-size:7.0pt;
color:#1F497D'> </span><span
style='color:#1F497D'>If the above part load efficiency curve is created based
on data where the 100% loading point corresponds to the maximum (not design)
capacity, should “DESIGN-PLR” (the ratio of design to maximum capacity) be set
to 1.00 and the capacity of the chiller be specified at its maximum (not
design) for the design/rated conditions? As I write this question it
sounds like I’m chasing my tail – someone straighten me out =)!</span><o:p></o:p></p>
<p><span style='color:#1F497D'>3.</span><span style='font-size:7.0pt;
color:#1F497D'> </span><span
style='color:#1F497D'>When you veterans finish a project with sets of custom
performance curves, do you have any suggestions for a naming scheme for future
reference/re-use? I’m currently thinking to keep the curves grouped in an
.inp snippet I for importing along with an equipment cutsheet… but I’m certain
I’ll forget the all the details as quickly as humanly possible when this
project is behind me…</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.25in'><span style='color:#1F497D'> ~Nick</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'> </span><o:p></o:p></p>
<div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='color:#1F497D'><img border=0 width=119 height=37 id="_x0000_i1028"
src="%20" alt="cid:489575314@22072009-0ABB"></span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='color:#2D4D5E'> </span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='color:#2D4D5E'>NICK CATON, E.I.T.</span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:7.5pt;color:#CC9900'>PROJECT ENGINEER</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;color:#2D4D5E'>25501 west valley parkway</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;color:#2D4D5E'>olathe ks 66061</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;color:#2D4D5E'>direct 913 344.0036</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span
style='font-size:10.0pt;color:#2D4D5E'>fax 913 345.0617</span><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><i><span
style='font-size:10.0pt;color:#2D4D5E'>Check out our new web-site @ </span></i><span
style='color:#1F497D'><a href="http://www.smithboucher.com" target="_blank"
title="blocked::www.smithboucher.com"><span style='font-size:10.0pt'>www.smithboucher.com</span></a></span><u><span
style='font-size:10.0pt;color:blue'> </span></u><o:p></o:p></p>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='font-size:10.0pt'>EIR-FPLR</span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>Takes
the U-name of a curve that adjusts the electric input ratio as a function of<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><span style='font-family:Symbol'>· </span><u>The part load
ratio (PLR)</u> – The PLR is defined as the ratio of the hourly load to
the hourly capacity; Load / Cap<sub>hour</sub><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:.5in'><span style='font-family:Symbol'>· </span><u>The
evaporator/condenser dT</u> - The temperature differential between the
condenser and leaving chilled-water. The meaning of the condenser
temperature varies according to condenser type. <o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;
margin-left:2.7pt'>For most chillers, the dT has a relatively small effect on
part-load performance. However, for variable-speed centrifugal chillers, the
effect of dT is as important as the PLR. This is because the pressure
rise across the impeller is proportional to the square of the impeller’s speed.
Unless some form on condenser temperature relief is employed to reduce the
temperature (and pressure) differential across the chiller at part load, the
performance of a variable-speed chiller may not be significantly different than
that of a constant-speed chiller.<o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>To
model power consumption as a function of the PLR only, use a CURVE-FIT of TYPE
= QUADRATIC or CUBIC. To model as a function of both PLR and dT, use a
BI-QUADRATIC-RATIO&DT curve. <b><span style='color:red'>The curve must be
normalized to 1.0 at full load and the rated temperature differential. </span></b><o:p></o:p></p>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span
style='color:red'>Note that, for centrifugal chillers, ‘full load’ is defined
as the ‘maximum capacity’, not the ‘design capacity’.</span></b> Refer to the
DESIGN-PLR keyword for more information.<o:p></o:p></p>
<p style='margin-bottom:12.0pt'> <o:p></o:p></p>
</div>
</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><br>
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</div>
<p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><br>
<br clear=all>
<br>
-- <br>
Carol Gardner PE<o:p></o:p></p>
</div>
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<p class=MsoNormal style='margin-bottom:12.0pt'><br>
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<p class=MsoNormal><br>
<br clear=all>
<br>
-- <br>
Carol Gardner PE<o:p></o:p></p>
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