[ShannonR]

How many volts is your system? The beginning of your post made me wonder if you are using a 12v inverter on a 24v (or more) battery bank. Or maybe your inverter is just on the 12v setting?

My charge controller handles the equalizing for me, can you program it to zap the battieries uniformly for a few hours? I can set how many hours I want to equalize for, usually 2-4 hours and I can also program the charge controller to charge to a specific voltage. For my 12v system, that would be 14.4v. For the purpose of trying to restore the batteries, longer may be good but keep an eye on the liquid levels because they're gonna boil good.

 

[ShannonR]

Hi Shannon

Thank you for your reply. Yes, I have a 12 volt battery bank. The manufacture say to bulk charge at 14.7 volts, which is slightly higher than yours. To equalize, I need to hold the charge at 15.6 volts. As regular maintenance (preventative charge), this should be done every two to six months, depending on how much abuse your batteries take. Until this recent inverter purchase, my batteries were in excellent condition. I ran the generator maybe 10 times since May, as we have a good cushion for cloudy days.

The low voltage has caused sulfation of the plates. I now need to a corrective equalization to try to bring the batteries back to usefulness. My immediate problem is, how long I should charge them for? When I separated the parallels, I did a 4 hour equalization. So, I have recovered them to the point that I can now equalize the whole battery bank, but they still have no storage capacity. I obviously need a longer charge, but how long is the question.

Try 6 hours the next time you equalize the bank as a whole. It may take several equalizing cycles to get the batteries back up to par. I have beaten up a pair of T-105's pretty well, but after several equalizing cycles they began to gradually hold a higher charge. You may see improvement in increments, as you have discovered already. I think that's pretty normal.