If you had, for instance, strings of quantity 10 PVL136 watt modules, and you needed to put in a 68 watt module because of a skylight, then you would want to use a string of 9 PVL136 watt + 2 PVL68 watt. This would keep the voltages the same between strings. Having a string of 9 PVL136 + 1 PVL68 paralleled with strings of 10 PVL136 would cause some of the strings to see non-optimal voltages. I don't see how bypass diodes would fix things.<br>
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Message: 1<br>
Date: Thu, 30 Oct 2008 13:29:38 -0700 (PDT)<br>
From: Geoff Greenfield <<a href="mailto:geoff@third-sun.com">geoff@third-sun.com</a>><br>
Subject: [RE-wrenches] mix-n-match Unisolar<br>
To: RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</a>><br>
Cc: Randy <<a href="mailto:Randy@third-sun.com">Randy@third-sun.com</a>><br>
Message-ID:<br>
<<a href="mailto:7296183.5724731225398578887.JavaMail.root@zimbra4.mindcentric.com">7296183.5724731225398578887.JavaMail.root@zimbra4.mindcentric.com</a>><br>
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I thought I knew the answer to this one, but wanted to run it by the list.<br>
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We are responding to a bid where the electrical engineer has designed a system with different sized Uni-solar laminates in some?series strings paralelled with consistant full size strings.? (this was done to work around skylights etc).<br>
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We suggested that this was a poor design and will lead to "least common denomenator" performance, exacerbated by MPPT confusion.? The EE responded that "the bypass diodes allow for this".<br>
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Any experience with this in practice?<br>
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For a brighter energy future,<br>
<br>
Geoff Greenfield<br>
Founder and CEO<br>
Third Sun Solar & Wind Power Ltd.<br>
340 West State Street, Unit 25<br>
Athens, OH 45701<br>
<br>
740.597.3111 ? ? Fax 740.597.1548<br>
<a href="http://www.Third-Sun.com" target="_blank">www.Third-Sun.com</a><br>
<br>
Clean Energy - Expertly Installed<br>
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