Ron, >From what Daryl said below and the fact that your customer has about 15 amps >of PV charge, you should deduct that the batteries have MOSTLY been deficit >charged their entire life. Here's what I told you on Oct 22 in my lengthy >explanation about what the problem is and why it happened: "Undersized RE >charging systems, or perhaps oversized batteries, is the culprit that >contributes to this all too frequent phenomenon of chronic undercharging."
You said that the customer has been compensating for an undersized system by running a generator. They can not know this because there is no monitor. The batteries now have a sulfation problem, perhaps unrecoverable, that could have been prevented if the owner had a battery capacity monitor. This is not pleasant news, I know. I have to explain this bad news to people MANY times each week. This is a huge issue globally. And such waste of money, time and resources just bugs me! Larry Crutcher Barer of Bad News Starlight Solar Power Systems On Nov 17, 2011, at 5:17 AM, penobscotso...@midmaine.com wrote: > Ron, > I'm going to reiterate what Jeff says here. It is similar to what I had > said in my email. The charge rate must REGULARLY be C10 on the KS > (5000 series) batteries. This means, on KS 25's, a routine bulk > charging rate of 135 amps. I find that on these types of hybrid > systems, while the batteries might occasionally (sunny day, generator > running, etc.) that kind of charging, they do not regularly see C10. I > think if you gave Jamie Surrette a call he would give you the same > possible assessment. > I do think the problem is oversulfation, but none of this solves your > problem, I know. We have been installing KS series batteries since they > came out and this necessity of regular C10 charging has been an > integral part of design for me for many years. > > Best, > Daryl > > > > >> Ron, >> >> >> >> This reply a little late since I have been off line a few days. I >> mentioned >> in a similar thread last year that I had an off grid home client I >> designed >> and installed in Idaho back in 1998 that had a Kohler 8.5 kw generator, a >> Trace 4024 inverter, two separate solar arrays and Outback charge >> controllers, and 16 Trojan "L-16" batteries. This system worked >> flawlessly >> for 7 years and only required the generator a few hours per month, then it >> was time to change the batteries. I replaced the Trojans with the same >> size >> battery made by Surrette and everything went to crap. They had to run the >> generator hours and hours to get them past an 80% charge and we had lots >> of >> problems with overloading the generator even though we did not make any >> program changes and used the same generator. The generator was replaced 2 >> years later but this system never worked like it did before the battery >> replacement. >> >> >> >> When researching all this at that time I had talked with Surrette, Trojan, >> and anyone else that might help and this is what I found out. Of course >> there are just my opinions based on these conversations, but it is my >> understanding that Surrette is a much longer life battery with much less >> water loss when comparing apples and apples, and I was told this was due >> to >> a different lead composition that Surrette uses than any other battery >> manufacturer. However, this difference requires a much longer >> absorption/taper off charge process or you will never get it past 80% >> charged. This of course is almost impossible to achieve with a generator >> or >> undersized solar array, and you really need a grid connection to fully >> charge these things. No doubt these would be great in some standby grid >> connected system but I no longer use them in off grid. This was also at a >> time when battery manufacturers were just discovering solar so maybe >> battery >> designs have changed. Again, I think Surrette is a good company and makes >> a >> great battery, but just not sure you can fully recharge them with a >> mid-sized generator. >> >> >> >> I also do not like using parallel battery layouts as its hard to keep one >> string from pulling down the other strings when there is a low performance >> cell so you might do a cell by cell check. >> >> >> >> Good Luck, >> >> >> >> Jeff Yago >> >> DTI Solar Inc. _______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org 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
