Hi All....thanks for the good feedback on this water pumping system. Many good ideas....It looks like this is a system which can be done. I will be looking for a relay that will have the necessary voltage characteristics which will have ~200VDC on one side being normally closed and 240VAC on the other side, normally open. <br>
Mark, Allan.....I am looking at the Grundfos SQFlex Battery Back up system brochure and it shows a SQFlex system running with a pressure tank in their example system. Additionally they brochure goes on to say that "the CU 200 Controller has terminals for a pressure switch, which will control the pump's on/off operation via the pressure in the storage tank. The pressure switch should be of a normally open configuration, where the contacts within the switch are in the open position when the pressure is below the maximum set-point. When the pressure in the system rises to the maximum desired pressure, the contacts will close signaling the pump to shut off." In researching further it looks like the float terminals in the CU 200 controller are able to be used for either a float switch or pressure switch. <br>
I don't have any experience running a pressure tank in line with the output of the system but I can't see why as Allan pointed out that it would know the difference between 40PSI in a pressure tank or an additional 100' of head. I think that it is important to recognize the additional head ( due to the pressure tank) that will be present and to take that into consideration when sizing the array for the desired amount of gpm production.<br>
If anyone has any recommendations for a relay or other switch which can handle 200VDC and 240VAC I would be grateful.....<br>Cheers,<br>-- <br>Sunny Regards,<br>Kirpal Khalsa<br>NABCEP Certified Solar PV
Installer<br>Renewable Energy Systems<br><a href="http://www.oregonsolarworks.com">www.oregonsolarworks.com</a><br>541-218-0201
m<br>541-592-3958 o<br><br><div class="gmail_quote">On Mon, May 24, 2010 at 2:42 PM, Mark Dickson <span dir="ltr"><<a href="mailto:Mark@oasismontana.com">Mark@oasismontana.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
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<p class="MsoNormal"><font color="navy" face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial; color: navy;">Allan, </span></font></p>
<p class="MsoNormal"><font color="navy" face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial; color: navy;">This is all Dwight at Genpro could tell
me. . .sorry to be vague! I agree, it seems like it would not know the difference.
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<p class="MsoNormal"><font color="#1f497d" face="Calibri" size="2"><span style="font-size: 11pt; font-family: Calibri; color: rgb(31, 73, 125);">I would love to shed
some light, however this was shared with us at the NGWA show by a Grundfos
Engineer. It has brochursomething to do with the thrust load bearing on a
them. Lorentz has two I believe Grundfos has one.</span></font><font color="navy" face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial; color: navy;"></span></font></p><div class="im">
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<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Best regards,</span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;"> </span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Mark </span></font><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Dickson,</span></font><font color="navy"><span style="color: navy;"></span></font></p>
<p><font color="navy" face="ArialMT" size="2"><span style="font-size: 10pt; font-family: ArialMT; color: navy;">NABCEP Certified Solar
PV Installer ™</span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Oasis Montana
Inc.</span></font></p>
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<p class="MsoNormal"><b><font color="black" face="Tahoma" size="2"><span style="font-size: 10pt; font-family: Tahoma; color: windowtext; font-weight: bold;">From:</span></font></b><font color="black" face="Tahoma" size="2"><span style="font-size: 10pt; font-family: Tahoma; color: windowtext;"> <a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" target="_blank">re-wrenches-bounces@lists.re-wrenches.org</a>
[mailto:<a href="mailto:re-wrenches-bounces@lists.re-wrenches.org" target="_blank">re-wrenches-bounces@lists.re-wrenches.org</a>] <b><span style="font-weight: bold;">On Behalf Of </span></b>Allan Sindelar<br>
<b><span style="font-weight: bold;">Sent:</span></b> Monday, May 24, 2010 2:39 PM<div><div></div><div class="h5"><br>
<b><span style="font-weight: bold;">To:</span></b> RE-wrenches<br>
<b><span style="font-weight: bold;">Subject:</span></b> Re: [RE-wrenches]
Grundfos SQ FLEX AC/DC auto switching</div></div></span></font><font color="black"><span style="color: windowtext;"></span></font></p>
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<p class="MsoNormal" style="margin-bottom: 12pt;"><font color="black" face="Times New Roman" size="3"><span style="font-size: 12pt;">Mark,<br>
Your message gave me pause, as I just last week specified this setup, so I
checked into it with our Grundfos rep. He said he had never heard anything
recommending against the flex in a pressure system. He said the SQF doesn't
know the difference between 40 psi and 100' of head. At the end of the day the
pump just stops. <br>
<br>
He did make a point of emphasizing the need for pressure relief valves, as the
helical rotor models can overpressure a system.<br>
<br>
Could you check with your distributor about this and post the reason you're
given, please?<br>
Allan</span></font></p>
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<p class="MsoNormal"><span><b><font color="black" face="Times New Roman" size="3"><span style="font-size: 12pt; font-weight: bold;">Allan</span></font></b></span><b><span style="font-weight: bold;"> Sindelar</span></b><font size="2"><span style="font-size: 10pt;"><br>
<a href="mailto:Allan@positiveenergysolar.com" target="_blank"><span>Allan</span>@positiveenergysolar.com</a><br>
NABCEP Certified Photovoltaic Installer<br>
EE98J Journeyman Electrician<br>
<b><span style="font-weight: bold;">Positive Energy, Inc.</span></b><br>
3201 Calle Marie<br>
Santa Fe, New Mexico 87507<br>
<b><span style="font-weight: bold;">505 424-1112</span></b><br>
<a href="http://www.positiveenergysolar.com/" target="_blank">www.positiveenergysolar.com</a></span></font></p>
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<br>
Mark Dickson wrote: </span></font></p>
<p class="MsoNormal"><font color="navy" face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial; color: navy;">Our Grundfos pump distributor has always warned against using
the SQF pumps in pressure pumping situations. I can’t quite
remember why, but you may want to check into that. The Lorentz HR’s
have been the choice in these situations.</span></font></p>
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<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Best regards,</span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;"> </span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Mark Dickson,</span></font></p>
<p><font color="navy" face="ArialMT" size="2"><span style="font-size: 10pt; font-family: ArialMT; color: navy;">NABCEP Certified Solar PV
Installer ™</span></font></p>
<p><font color="navy" face="Comic Sans MS" size="2"><span style="font-size: 10pt; font-family: "Comic Sans MS"; color: navy;">Oasis Montana
Inc.</span></font></p><br></div><p class="MsoNormal"><font color="black" face="Times New Roman" size="3"><span style="font-size: 12pt;">
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