<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Wayne,<div>First, let's hope you mean 12 of the 2YS31. A single battery string is always preferable to multiple strings in my book. The only downside is interconnect cables the same size as your inverter cables. That probably means 4/0 CU for most 24V, 3KW and up inverters. Two strings in parallel-not too bad. Three strings- as far as you want to push it. More strings- Don't go there.</div><div>Bob-O</div><div><br><div><div>On May 31, 2011, at 2:49 PM, Wayne Irwin wrote:</div><br class="Apple-interchange-newline"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div class="hmmessage" style="font-size: 10pt; font-family: Tahoma; ">Hello Esteemed Battery Gurus,<br><br>Which of the following do you believe is the better 24 V battery bank?<br><br>A) 13 - Rolls 2-YS-31 2430 AH @ 20 HR (one string)<span class="Apple-converted-space"> </span><br><br>or<span class="Apple-converted-space"> </span><br><br>B) 9 - Rolls 8-CS-25P 820 AH @ 20 HR (3 strings of 3)<br><br>Thank you in advance for your input!<br><br><br><font color="#76923c">Wayne Irwin</font><font color="#76923c">, EE<br>Director of Engineering<br></font><font color="#76923c">Pure Energy Solar International Inc.<span class="Apple-converted-space"> </span></font><font color="#76923c"><br></font><font color="#76923c"></font><font color="#76923c">State Licensed Solar Contractor</font><font color="#76923c"><br></font><font color="#76923c">License # CVC56695<span class="Apple-converted-space"> </span></font><br><a href="mailto:PureEnergySolar@hotmail.com">Wayne@PureEnergySolar.com</a><span class="Apple-converted-space"> </span><br><a href="http://pureenergysolar.net/" target="_blank">http://pureenergysolar.com</a><span class="Apple-converted-space"> </span><br><font color="#76923c">352 377-6527 Office</font><font color="#76923c"><br></font><font color="#76923c">352 336-3299 Fax</font><font color="#76923c"><br></font><font color="#76923c">352 316-1637 Cell</font><br><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; "><font color="#76923c"><span style="font-size: 10pt; font-family: Arial, sans-serif; ">The content of this message is Pure Energy Solar Confidential. If you are not the intended recipient and have received this message in error, any use or distribution is prohibited. Please notify me immediately by reply e-mail and delete this message from your computer system. Thank you.</span></font></div></div></span></div></div></body></html>