Need Help with Charge Controller Settings..

Coach Dad
Coach Dad Solar Expert Posts: 154 ✭✭
I have 4 Sun-Extender AGM batteries. They are 6 volt 305 AH each. They will be wired in Series to give me 24 volts 305 AH. The manual indicates that the
Absorbtion Voltage should be between 28.4V to 28.8 V
Float Voltage should be between 26.4 to 26.8V
Equalize voltage should be 31 V

I have a Tri-Star MPPT 60 Amp Charge Controller (TSMPPT60) which I’m getting ready to install. But the setting listed in the Tri-Star manual don’t match the Battery requirements.
This is the table from the Tri-Star Manual. (see attached)
If I multiply these by 2 none of them match… Which settings should I use???


  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Need Help with Charge Controller Settings..

    Not much help but as a start I would contact both manufacturers to see what they recommend
    KID #51B  4s 140W to 24V 900Ah C&D AGM
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    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • BB.
    BB. Super Moderators, Administrators Posts: 33,501 admin
    Re: Need Help with Charge Controller Settings..

    2, 3, or 4 would be fine... And I think you can set manual equalization (once every 6 months?).

    If you are lightly cycling the battery bank and hit float early in the day, choose #2. If you cycle the batteries heavy, andwinter use, pick 3 or 4 to charge quicker and higher current.

    Of course, there is buying the dongle and programing your own settings.

    I am not sure I would realize with 31 volts unless I was having low battery capacity issues... But I am not a battery engineer.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset