morningstar ts-mppt-45

recently my ts-mppt-45 started charging in absorb mode at 15.1v to 15.2v. it used to be 14.7v to 14.8v. I have 6 100w panels connected.16 marine deep cycle batteries. everything is connected at 12v. I cant figure what might be wrong. any info? thanks.

Comments

  • WNY Dave
    WNY Dave Registered Users Posts: 23 ✭✭
    Re: morningstar ts-mppt-45

    Do you have Temperature compensation? Is it cold where you are?
  • dirt4b
    dirt4b Registered Users Posts: 4
    Re: morningstar ts-mppt-45

    yes I have temp,comp. connected. battery sense connected. I am in ohio. bank is in garage around 40 to 50 deg F
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: morningstar ts-mppt-45
    dirt4b wrote: »
    yes I have temp,comp. connected. battery sense connected. I am in ohio. bank is in garage around 40 to 50 deg F

    Cold batteries need higher charging voltage. Sounds like your controller is doing its job very well. --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • dirt4b
    dirt4b Registered Users Posts: 4
    Re: morningstar ts-mppt-45

    thanks for the info. will 15.1 to 15.2v over charge my bank? hurt the batteries? I turned up the heat in garage. everything is golden now. thanks!
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: morningstar ts-mppt-45

    If you are not using too much water (say having to refill every month or more often), then everything is probably OK (you are logging temperature corrected specific gravity of each cell every month?).

    Cold batteries have less capacity at colder temperatures, but they can last much longer (for every 10C below 25C, their life will double--All else being equal--which it rarely is).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: morningstar ts-mppt-45
    dirt4b wrote: »
    recently my ts-mppt-45 started charging in absorb mode at 15.1v to 15.2v. it used to be 14.7v to 14.8v. . I cant figure what might be wrong. any info? thanks.

    My batteries are at the moment 6*C, which is 42*F, and today they too were temp corrected by my TS-MPPT-60 to 15.1V absorb. I'd have to say everything is very likely as it should be. Come Summer and warmer temps, the voltage will drop back down again.
    Earlier this Winter during a very cold spell and before I insulated the battery box for the Winter, the battery temp had dropped to Minus 8C (17F) and the TS had upped the absorb voltage to 15.5, which is normal and necessary given the battery temp.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: morningstar ts-mppt-45

    The major issue to watch out for (ignoring the batteries), is the "high battery" bus voltage...

    A fair number of devices (inverters, "12 volt" DC adaptors, etc.) do not really like voltages above ~14.5 to 15.0+ range. You may have to find different AC inverters (i.e., find an inverter with Vbatt>16.0 volts) and/or shutdown the devices you can live without during sunny afternoons, etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: morningstar ts-mppt-45
    BB. wrote: »
    The major issue to watch out for (ignoring the batteries), is the "high battery" bus voltage...

    A fair number of devices (inverters, "12 volt" DC adaptors, etc.) do not really like voltages above ~14.5 to 15.0+ range. You may have to find different AC inverters (i.e., find an inverter with Vbatt>16.0 volts) and/or shutdown the devices you can live without during sunny afternoons, etc.).

    -Bill
    Bill is correct. My Morningstar inverters shut down at 15.5, the Xantrex holds on till at least 16 volts.
    I also have a couple of MSW inverters (no longer in use) that won't take over 14.8 volts. But remember, cold batteries need higher voltages for proper charging.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: morningstar ts-mppt-45
    BB. wrote: »
    Cold batteries have less capacity at colder temperatures, but they can last much longer (for every 10C below 25C, their life will double--All else being equal--which it rarely is).

    I think that if you use your batteries, cold temperatures will shorten their life. Batteries are dying in several ways at once. Cold temps will help with corrosion and self discharge, but will put greater demands on the cycle life. Furthermore, the internal resistance and the Peukert effect are increased, both of which also work against cycle life.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i