What would happen?

dazza159dazza159 Posts: 4Registered Users
What would happen if you used another dc source on an mppt charge controller in the solar panel port?
I'm thinking of the 12v power socket in my car to the solar input. A kind of dc to dc charger when I'm driving as my panels aren't fixed on.


  • PhotowhitPhotowhit Posts: 4,708Solar Expert ✭✭✭✭
    Without regard to your direct question, the voltage would be too low to charge through a MPPT type charge controller.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Prosine 1800 and Exeltech 1100, ForkLift battery. Off grid for @13 of last 14 years. 1000 watts being added to current CC, @2700 watts to be added with an additional CC.
  • dazza159dazza159 Posts: 4Registered Users
    Ok thanks, just thought I'd ask the question 👍
  • mike95490mike95490 Posts: 7,917Solar Expert ✭✭✭✭
    And if you use a higher voltage, it won't respond the way a PV panel does as the MPPT circuit try's to control the power.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • mcgivormcgivor Posts: 2,219Solar Expert ✭✭✭✭✭
    You could, if the battery that needs chaging is 12V, connect directly to the car battery, the alternator will do the rest, just be careful if it's an AGM, flooded would be fine, always incude an appropriate fuse to protect the wiring.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery bank 

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