Okay, with full sun and the Battery Minder pouring Unlimited Cosmic Power into the batteries, I achieve a state of green-light-blinkery on the controller which the manual says is “PWM Absorption.” I take that to mean the batteries are full.
Now I’d like to do a battery equalization. But the highest voltage I’ve ever seen is a hair under 14.2, and the charge controller is set to a max of 14.4. Does this mean 14.15 is the most voltage I can muster? Because equalization, according to the manual, requires something in excess of 16 volts. Or is that 14.15 figure what the controller is actually limiting the voltage to, and when I set it for equalization it’ll go higher?
16-PLUS VDC for a 12V system equalize?! That’s… _high_ for conventional lead-acid batteries. What kind of batteries do you have?* Is that manual for the _batteries_ or for the charger?
Roughly speaking, you want to float lead-acids around 2.17V per cell, or 13.02 for the battery. Your equalize voltage can vary some, but shoot for something around 14.15. I normally wouldn’t recommend going over 14.4, which conveniently is what you say the controller will max out to. Granted, that’s for an ideal constant charger input system (like my old telecom battery strings); your solar set runs a little higher float to allow for low input conditions.
If you do manage to get 16V, don’t equalize for more than an hour (that might be a bit much), and watch the battery string carefully for heating and excessive outgassing. I’d think that 16V would be more for _rejuvenation_ of old crapped out batteries than for an equalize charge.
* Absolyte, and Chloride batteries, just for instance, do require higher float voltages, but even those you’d equalize at about the same voltage as lead-acid. Double-check your battery _type_ and the number of cells (_should_ be 6 cells, but maybe you have something weird), and I’ll go back to my tables for exact voltages.
“Or is that 14.15 figure what the controller is actually limiting the voltage to, and when I set it for equalization it’ll go higher?”
Most likely the controller is limiting, and has a higher voltage limit when you set the controller to equalize mode.
While 16 V is high it is not outrageous, if that’s what the battery manual says, use it. Some earlier batteries of your acquaintance wanted 15.2 or more for 4 hours to equalize, or 15.4 followed by 4 hours of constant current charging to rejuvenate.
While your PV system supply the higher voltages?
Good luck!
-s