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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>From my personal experience…<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'>Not true. If you put 80Aoutput potential on the input of a 40A PWM controller, the output breaker will trip (assuming it is a 40A breaker). If there is not an output breaker, you will smoke the controller. The C-40 does not have a output current limit setting, like most MPPT controllers.<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'>This is not the case for a MPPT controller (generally speaking). I use MPPT controllers to charge 12V battery banks from 48V banks. I tried using a PWM controller for this purpose and found that it did not work…<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'>Good luck!<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'><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'><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"'> re-wrenches-bounces@lists.re-wrenches.org [mailto:re-wrenches-bounces@lists.re-wrenches.org] <b>On Behalf Of </b>Chris Mason<br><b>Sent:</b> Thursday, October 25, 2012 5:50 AM<br><b>To:</b> RE-wrenches<br><b>Subject:</b> Re: [RE-wrenches] C-40 question<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'>It does "take". Your charge controller controls the load and current, hence the name "controller". It is not a fixed resistance. If you program a charge rate limit, the controller will control the current flow to limit the charge rate, hence it is "taking" a certain current up to the limit of the source's ability to supply that current but not above, regardless of the size of the array.<o:p></o:p></p><div><p class=MsoNormal>On Wed, Oct 24, 2012 at 10:17 PM, Richard L Ratico <<a href="mailto:Richard.L.Ratico@valley.net" target="_blank">Richard.L.Ratico@valley.net</a>> wrote:<o:p></o:p></p><p class=MsoNormal>Huh? The equipment does not "take" or "draw" anything. The electrical pressure<br>of the source, called voltage, forces electrons through the load. Electrons per<br>unit time are called current. The current is only limited by the resistance of<br>the load, in accord with Ohms Law. The resistance of the load acts as a valve or<br>choke point in the circuit, thus limiting the current. In the case Allan<br>describes, the battery is the primary resistance in the circuit. If the battery<br>was large enough and, or, sufficiently discharged (low resistance), and the<br>source could provide enough current, the C-40 would "Toast".<br><br>Dick Ratico<o:p></o:p></p><div><p class=MsoNormal><br>--- You wrote:<br>Because it is not 80 amps current flowing, it is a capacity of 80 amps.<br>Think of it this way. Your toaster is plugged into an outlet that is<br>powered by the grid. The grid has infinite capacity. Why doesn't your<br>toaster explode? Because it takes the current it needs. Now, increase the<br>voltage and you may have a runaway current situation, but at the design<br>voltage the equipment takes the current it needs up to the limit if the<br>supply.<o:p></o:p></p></div><p class=MsoNormal>--- end of quote ---<o:p></o:p></p><div><div><p class=MsoNormal style='margin-bottom:12.0pt'>_______________________________________________<br>List sponsored by Home Power magazine<br><br>List Address: <a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br><br>Options & settings:<br><a href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a><br><br>List-Archive: <a href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank">www.re-wrenches.org/etiquette.htm</a><br><br>Check out participant bios:<br><a href="http://www.members.re-wrenches.org" target="_blank">www.members.re-wrenches.org</a><o:p></o:p></p></div></div></div><p class=MsoNormal><br><br clear=all><o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <br>Chris Mason<o:p></o:p></p><div><p class=MsoNormal>President, Comet Systems Ltd<o:p></o:p></p></div><div><p class=MsoNormal><a href="http://www.cometenergysystems.com" target="_blank">www.cometenergysystems.com</a><o:p></o:p></p></div><div><p class=MsoNormal>Cell: 264.235.5670<o:p></o:p></p></div><div><p class=MsoNormal>Skype: netconcepts<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></body></html>