Allan - Good point. With that in mind I would revise my loss estimate upwards. I would be very curious to hear from anyone with actual experience with this type of situation.
Andrew Truitt Truitt Renewable Energy Consulting 202 486-7507 http://www.linkedin.com/pub/andrew-truitt/8/622/713 Please excuse brevity and typos - this message was typed on tiny keys. On Jan 15, 2011 11:02 PM, "Allan Sindelar" <[email protected]> wrote: A little more musing here...and I'm looking for others' opinions on this theoretical piece. If you have two unmatched strings, won't the string with the larger Imp define the MPP of the inverter? If so, I would expect that the weaker string would be forced to operate at the Imp of the stronger string. If the stronger string operates at a higher Vmp, it will pull the weaker string's operating voltage above its own MPP, which could pull the current down substantially as voltage moved from Vmp toward Voc. Conversely, if the stronger string operates at a lower Vmp, it will pull the weaker string's operating voltage back toward its own MPP, which would maintain approximately the same current at a slightly lower voltage. This would reduce output slightly, but not nearly as much as in the other direction. Does this make sense? And does real-world experience bear this out? Allan Sindelar [email protected] NABCEP Certified Photovoltaic Installer EE98J Journey... > > Friends: > > I have a client with a Xantrex GT2.8 inverter. Feeding it are 8 Solar World SW175... _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] > > Options & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > ... _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] Options & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
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