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Hi bob,<div><br></div><div>Wow now thats unusual!</div><div><br></div><div>So have you figured out a better charger or are using a IBE or similar?</div><div><br></div><div>jay<br><div><div>On Aug 3, 2008, at 6:02 PM, robert ellison wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div dir="ltr"><div>The 80 volt battery banks are not on inverters, sorry I didn't mention that.</div> <div>They are 2 - 20 cell packs in series for 80 volts total.</div> <div>These power a Zamboni. I didn't know what one of those was either when they called me to work on the batteries 10 or so years ago.</div> <div>These are the machines that groom the ice on skating rinks, in most cases you can't use an engine inside a building anymore, so they are going electric. <div>I did put out some feelers a few years ago about building a 3 stage charger to charge them. Many are still using the transformer based, taper type charger we got away from years ago.</div> <div> </div></div> <div>It's another cool toy I get to play with.</div> <div> </div> <div>Later,</div> <div>Bob<br><br></div> <div class="gmail_quote">On Sat, Aug 2, 2008 at 12:31 PM, jay peltz <span dir="ltr"><<a href="mailto:jay@asis.com">jay@asis.com</a>></span> wrote:<br> <blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <div style="WORD-WRAP: break-word">HI Bob, <div><br></div> <div>What are you using 80v battery banks for or which inverters anyway?</div> <div><br></div> <div>Would be great for larger systems.</div> <div><br></div> <div>thanks,</div> <div>jay</div> <div>peltz power</div> <div> <div></div> <div class="Wj3C7c"> <div><br></div> <div><br> <div> <div>On Aug 1, 2008, at 10:18 PM, robert ellison wrote:</div><br> <blockquote type="cite"> <div dir="ltr"> <div>When i went to an SEI class at the Trojan factory one of the points mentioned was that the best way to get the lowest cost per watt from the battery bank</div> <div>(T-105's were at the time the lowest) was to cycle them to 80% discharge then fill them all the way up. Not feasible in an off grid system at all.</div> <div>We get more years life by just taking off the top 20 - 25% and returning it daily.</div> <div> </div> <div>My battery distributor says that an industrial deep cycle battery needs to be cycled occasionaly to prevent them developing a "memory" so to speak. </div> <div>I recommend to my customers that they occasionally let them run down to 50 -60% DOD and fill them back up with an EQ charge to stir up the electrolyte so you can get an accurate reading with a hydrometer.</div> <div>Stratification will throw off the gravity readings unless they get stirred up occasionally. </div> <div>I have pulled apart batteries that did not get an EQ and found the bottom of the plates wore out and the top still looking reasonably good. That is from the acid being a lot stronger at the bottom than the top and just working on the bottom of the plates in the battery. This is not a "fun" project and usually results in some trashed clothes, rubber suit or not.</div> <div> </div> <div>I have 80 volt battery packs that get cycled to 70-80% DOD daily for 5 months a year then sit for 7 months with just a couple freshening charges and last 6 - 7 years till wore out, some of these are hi acid batteries that are in the specific gravity range or 1.325 or more when fully charged instead of the usual 1.265 -1.270 that we are used to seeing.</div> <div> </div> <div>I am not a battery "expert" I just have several big banks that I maintain and have formed some opinions over the last 15 or so years.</div> <div>I have also experienced wearing out a set of L-16's by hitting the end of their cycle life in just over a year. It was way too small a battery bank and got cycled fully almost daily hitting it's cycle life limit far sooner than a larger bank would have if treated well.</div> <div> </div> <div>Good night,</div> <div>Bob </div> <div> </div> <div> </div> <div><br><br> </div> <div class="gmail_quote">On Sat, Aug 2, 2008 at 12:01 AM, jay peltz <span dir="ltr"><<a href="mailto:jay@asis.com" target="_blank">jay@asis.com</a>></span> wrote:<br> <blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <div style="WORD-WRAP: break-word">Hi Robert, <div><br></div> <div>When you mention cycling batteries, are you saying that batteries in a offgrid system that are being cycled 15-25% a day should be cycled even deeper than that?</div> <div><br></div> <div>Thanks,</div> <div><br></div> <div>jay </div> <div>peltz power <div><br> <div> <div>On Aug 1, 2008, at 8:36 PM, robert ellison wrote:</div><br> <blockquote type="cite"> <div dir="ltr"> <div>A couple things that I haver noticed in the past, sometimes batteries like to be cycled, shut off the controllers and run them down, then charge them up fully and then give them an eq charge till it comes up the peak voltage and hold it there as it (sometimes) slowly rises. Any of these thoughts are superseded by Jamie if he has any thoughts. </div> <div> </div> <div>Also, if you have not given them an eq in a while it might take longer than the available solar time has to get them to the top and hold them there..</div> <div>Have the controllers settings changed?<br></div> <div> </div> <div>Bob<br></div> <div class="gmail_quote">On Fri, Aug 1, 2008 at 10:18 PM, Allan Sindelar <span dir="ltr"><<a href="mailto:allan@positiveenergysolar.com" target="_blank">allan@positiveenergysolar.com</a>></span> wrote:<br> <blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"> <div><p><font face="Arial">Wrenches,</font> <br><font face="Arial">In late 2003 we installed a 24V set of Rolls-Surrette 4-KS-21PS 6V 1104 A/hr batteries in the off-grid system of a long-time client. The client's system had a democracy array of around 800 watts of tracked PV. In early 2005 we added 1,280 watts of additional PV, and the client hasn't run the generator since; the system rarely drops below 80% and fills to 100% most days in sunny New Mexico. Batteries are located in a basement, so temperatures stay relatively constant, although it will vary slightly seasonally. MX60 controller is temperature compensated, with 29.6 VDC bulk and 31.4 VDC EQ set points.</font></p><p><font face="Arial">The problem is that the client reports being unable to achieve previous EQ voltages, and this inability appears to be a new development. The system is otherwise performing well. As the client is sharp and pays close attention to the system's operation, I'm not ready to blame user ignorance (with one possible exception; read on). This may be an issue of seasonally warm temperatures, but I'm not sure this would explain the full 0.4 VDC reduction in voltage. I told him that I would post his problem to this list, and also request advice from Surrette Battery.</font></p><p><font face="Arial">Here is the client's description of the symptoms:</font> <br><font face="Arial">I'm concerned that I am unable to equalize batteries at this time. Up</font> <br><font face="Arial">until June of this year the Tri-Metric readings during equalizing indicated</font> <br> <font face="Arial">holding voltage at 31.1, with maximum amps gain of around 52. Three weeks</font> <br><font face="Arial">ago, when set on equalize, the maximum voltage reading was 30.7, with</font> <br><font face="Arial">maximum amps of 46; this was reached around noon, and by around 1:30 pm</font> <br> <font face="Arial">voltage/amps began its typical afternoon drop-off. I attempted equalizing</font> <br><font face="Arial">on two other occasions since then--the last time this past Saturday, with</font> <br><font face="Arial">clear skies up until mid-afternoon--but having the same results. So, the</font> <br> <font face="Arial">question is: are my batteries beginning their decline? We've had this set</font> <br><font face="Arial">for 4 1/2 years, so it would seem a bit too early for this, given that these</font> <br><font face="Arial">batteries are expected to last 7-10 years.</font> </p><p><br></p></div></blockquote></div></div></blockquote></div></div></div></div><br>_______________________________________________<br>List sponsored by Home Power magazine<br><br><a href="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank">RE-wrenches@lists.re-wrenches.org</a><br> <br><a href="http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org</a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank">http://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><br><br><br></blockquote></div><br></div> <div style="MARGIN: 0px">_______________________________________________</div> <div style="MARGIN: 0px">List sponsored by Home Power magazine</div> <div style="MIN-HEIGHT: 14px; MARGIN: 0px"><br></div> <div style="MARGIN: 0px"><a href="mailto:RE-wrenches@lists.re-wrenches.org" target="_blank">RE-wrenches@lists.re-wrenches.org</a></div> <div style="MIN-HEIGHT: 14px; MARGIN: 0px"><br></div> <div style="MARGIN: 0px"><a href="http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org</a></div> <div style="MIN-HEIGHT: 14px; MARGIN: 0px"><br></div> <div style="MARGIN: 0px">List rules & etiquette:</div> <div style="MARGIN: 0px"><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank">http://www.re-wrenches.org/etiquette.htm</a></div> <div style="MIN-HEIGHT: 14px; MARGIN: 0px"><br></div> <div style="MARGIN: 0px">Check out participant bios:</div> <div style="MARGIN: 0px"><a href="http://www.members.re-wrenches.org/" target="_blank">www.members.re-wrenches.org</a></div> <div style="MIN-HEIGHT: 14px; MARGIN: 0px"><br></div></blockquote></div><br></div></div></div></div><br>_______________________________________________<br>List sponsored by Home Power magazine<br><br><a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a><br> <br><a href="http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org" target="_blank">http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org</a><br><br>List rules & etiquette:<br><a href="http://www.re-wrenches.org/etiquette.htm" target="_blank">http://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><br><br><br></blockquote></div><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">List sponsored by Home Power magazine</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">List rules & etiquette:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><a href="http://www.re-wrenches.org/etiquette.htm">http://www.re-wrenches.org/etiquette.htm</a></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Check out participant bios:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">www.members.re-wrenches.org</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div> </blockquote></div><br></div></body></html>