Below is a essay by Richard Perez, the Editor, Publisher, and Founder of Home Power Magazine I copied from the magazine for those who are interested.
Norm S/V Bandersnatch Lying NYC Battery equalizing is a controlled overcharge of the batteries to maximize their life. Daily I use the amp/hour meter to determine overcharge and try to overcharge the batteries by at least 2% of their capacity. Weekly I set the PV regulator to equalize and overcharge the batteries by at least 5% of their amp/hour capacity. Monthly I use the generator to overcharge the batteries by 10% of their capacity. I don't pay attention to the battery voltage during equalization, but to the amount of overcharge (in amp/hours) that the battery receives. I don't routinely do hydrometer measurements. This regimen requires having an array large enough to not only meet electrical consumption demands, but also to provide the needed overcharge. If your array cannot do this consider adding more modules. If the array is not up to the job, then an generator must be used. I try not to use the batteries too heavily. My average depth of discharge nightly is about 12% of battery capacity. On most sunny days, the battery is fully recharged before noon, and then the daily overcharge begins. If the battery drops below 30% depth of discharge I start the generator. I use the generator an average of 160 hours per year - mostly during the depth of Oregon's cloudy winters. Battery makers and distributors are just now becoming aware of the type of cycling that a battery sees in PV service. Their usual recommendations are for batteries that are deeply discharged, then refilled rapidly - a far tougher service that in a well-designed PV system. If you are using the generator to equalize, do it at least monthly. Voltage doesn't matter - it's the amount of overcharge amp/hours that matter. Recharge until the amp/hour meter shows a 10% overcharge and don't forget to add water to the electrolyte as needed. Richard Perez, Home Power Magazine _______________________________________________ Liveaboard mailing list [email protected] To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [email protected] To unsubscribe send an email to [email protected] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/[email protected] The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
