MPPT charge controller input 100V and 0A

anwartota9anwartota9 Registered Users Posts: 1
Hello, I have 5 24v 250W panels and 1 24v 260W panel, so total of 6 panels. I bought Inverter with built-in 60A MPPT charge controller. When I connect all the panels in parallel, I get 25A max at peak. I tried to contact 3 panels in searies and connected them in parallel with the other 3 panels, so I should get around 100V and 15A, but I get 100V and only less than 0.5A.
I tried to disconnect three and keep only 3 panels in series, but I am still having the same reading even after swapping. However, when I measure the Isc for any of the 3 panels it gives me 7A.
Could you suggest any troubleshooting methods before I return the unit.



  • AguarancherAguarancher Solar Expert Posts: 315 ✭✭✭
    You might try 2 panels in series. 3 in series may be over voltage for your inverter. What is the inverter/cc you are using?
  • zonebluezoneblue Solar Expert Posts: 1,218 ✭✭✭✭
    Well hi and welcome to the NAWs forum.  I would caution you about trying various configurations out without having a good read of the product manual. You dont want to overvoltage the controller, that tends to be bad. In general with mppt you want the input voltage to be about 1.5 to 2 times the battery voltage. Now you mention a combined inverter charge controller. In my experience these are typically chinese units. Best will be you list out the gear you have, and how its configured, as that will help folk in answering. But the ballpark about what you might realistically expect is somethign like this:

    1500Wp, assuming 24V battery, noon sunny day, good array orientation/shade free etc
    =1500W * 0.77 pv/cc derating =1150W
    =1150W /24V = 48A charge rate

    For northern hemisphere winter youll need to take off maybe another 15%.

    NB:  this post belongs in either general, or off grid, not installers.

    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,

  • BB.BB. Super Moderators, Administrators Posts: 32,639 admin
    OK--I have moved this to the Off Grid section...

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