<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">HI Ray,<div><br></div><div>What charge parameters are you using if you are not doing an EQ.</div><div>volts absorb and volts float and absorb time?</div><div><br></div><div>thanks,</div><div><br></div><div>jay</div><div><br></div><div>peltz power<br><div><div>On Nov 7, 2009, at 12:45 PM, R Ray Walters wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">I think that periodic Equalization is "old school", a concept left over from the days of C30 controllers that didn't fully charge the batteries on a regular basis. <div>I now only recommend Eq charging if:<div>a) the batteries have sat for over a month in a deeply discharged state, or</div><div>b) checking individual cell voltages indicates more than a 2% difference between batteries. (over a tenth on a 6 v battery)</div><div>Eqing every 30 days just isn't necessary with today's PWM temp compensated controllers IMHO.</div><div>Equalization charging can overheat batteries, which according to my research is the number one factor in reduced life.</div><div>Also, even when Eqing, I recommend the generator only be used to bring the batteries up to close to full charge, and then let the PV array perform the Equalization, thus the MATE isn't necessary.</div><div>I still do install MATEs on projects with owners that know what they're doing, and know when to equalize, etc.</div><div>Finally, its very inefficient to use a generator for the hours necessary for Equalization while running at fairly low power.</div><div>Hit the genie early in the morning, shut down most loads, and Eq with the array from 11:00am through the afternoon. If the array can't do this, then its undersized, or you have designed a highbred system that does require a MATE. (and an owner that understands what he's doing)</div><div><br><div> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>R. Walters</div><div><a href="mailto:ray@solarray.com">ray@solarray.com</a></div><div>Solar Engineer</div><div><br class="khtml-block-placeholder"></div><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span> </div> </div></div></div></blockquote></div><br></div></body></html>