Wiring incorrect?

wolkcreekii Registered Users Posts: 1
When my pump turns on it uses the battery power instead of the solar power. When the batteries run out of power the inverter does not get the solar power to keep running, so shuts off. Then the charge controller will recharge the batteries. seems to me the solar array should power the inverter and not need the batteries except as backup power when the solar power generation is too low. What am I doing wrong? Thank you.


  • MichaelK
    MichaelK Registered Users Posts: 234 ✭✭✭
    edited September 2022 #2
    Sounds like the solar input is not large enough to handle the load, and that has to come from the batteries.  A good rule of thumb that has worked well for me is that the solar watts should be at least 2X the running watts of your single biggest load.

    So, how big is the pump?  How many watts does it consume while running.  Before you get any more meaningful answers, you need to first supply more information about your system voltage, solar array, inverter capacity, battery size, and pump draw.
    System 1) 15 Renogy 300w + 4 250W Astronergy panels,  Midnight 200 CC, 8 Trojan L16 bat., Schneider XW6848 NA inverter, AC-Delco 6000w gen.
    System 2) 8 YingLi 250W panels, Midnight 200CC, three 8V Rolls batteries, Schneider Conext 4024 inverter (workshop)
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    I pretty much agree with MichaelK, Could you describe the load in watts and solar array/charge controller?

    I often run a window air in my main room at about 1000watts (14,000 btu LG) along with my 6000btu in the back bedroom 500 watts.  During the day with solar support. I have a 4500 watt array and I usually wait until it's in absorb because the system charges very slowly. Even with minimal clouds (still distinct shadows) I have a hard time doing this! 
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.