how to equalize my solar batteries

Can any one help Ihave a stand alone system which consits of 9x170w solar panels on three trackers,Ouutback VFXinverter/charger,MX60 solar charger,hub,mate, 12x2v 1320Ah c120 opzs exide solar batteries and a 9kva generater.The problem is Ive been told that I need to equalize the batteries,but when I speak to Outback or Exide they will not give me figures to enter into the outback Current limit.Absorbing time limit.Absorb end amps.Rebulk voltage.How long to run the equalize for,and what should I be looking for.Should the batteries reach there full charge before they start to equalize,using the generator to equalize the system,and what should the charge limit settings be for these type of batteries.
Any help whould most gratefull.


  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: how to equalize my solar batteries

    Welcome to the forum.

    Let's go for the basic numbers. You can adjust from there when you see the results.
    The first number is the Absorb set point. On a 24 Volt system using Flooded Lead Acid batteries this is usually 28.8. Some battery manufacturers recommend more, others less. Make sure you have the Remote Temperature Sensor, as there can be quite a bit of difference between hot and cold batteries.
    On Outback systems the Absorb time is automatically determined by the Bulk time: when Bulk charging begins the clock starts running. Whatever time is on it when Absorb Voltage set-point is reached is how long the Absorb cycle will run for. As a rule you do not need to be concerned about Absorb end Amps except in certain cases.
    Float Voltage on a 24 Volt system is usually 27.6. Again +/- depending on what you find works best. Another parameter to set is the Low Voltage Disconnect, which ought to be system nominal (24 Volts). You can go lower than that, but it will eat into battery life.
    Equalization is usually done at 31 Volts. You must go through a full charge cycle before running an EQ cycle. If you need to you can run the gen and Bulk the batteries up faster than the PV alone will do, then allow the PV to finish the Absorb cycle and do the Equalization. I'm not familiar with that particular battery, but if they don't have removable caps and cells you can take a Specific Gravity reading from (use a hydrometer) do not equalize them. For the most part, this is not a process for sealed batteries. You should run the EQ for one hour and see if there is any improvement in cell SG. If there is and they are still unequal, do it again. If you stop seeing improvement, stop equalizing. Too much will be bad for the batteries.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: how to equalize my solar batteries

    I found what appears to be some tech data on the Exide OPzS batteries:
    You'll have to do some reading and figuring, but they appear to be fairly Voltage tolerant, but you might want to dial back from the numbers I gave.
  • VicVic Solar Expert Posts: 2,810 ✭✭✭✭
    Re: how to equalize my solar batteries

    And, please review this thread, and a link posted by BB:

    BB's link is a bit over technical, but I have only scanned it quickly. More later, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
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