is a 38V solar panel considered 36V panel?

hmong2017hmong2017 Registered Users Posts: 39 ✭✭

Solar Panel SPecs:


Maximum Power 335W

Maximum Power Voltage 38V

Maximum Power Current 8.82A

Model GCL-P6/72335


  • PhotowhitPhotowhit Solar Expert Posts: 5,729 ✭✭✭✭✭

    No, it would be designed for charging a 24 volt battery banks.

    Charging a 24 volt battery bank with an inexpensive PWM charge controller, this will reach high enough voltages to properly charge a 24 volt battery bank, which might reach 32 volts or some flooded types when equalizing.

    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, 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.
  • SolfyrSolfyr Registered Users Posts: 22 ✭✭

    Depends on Temperature ...

    At low temperatures at freezing point , it might output more than 38 Volts .

    The Temperature Coefficient for the Voltage needs to be calculated from

    percent % to Volts .

    If that panel has a Tempcoeff of 0.3% , then the Voltage falls on lower temperatures than those 25°C by

    0.11 V each Celsius . At 0°C it could probaby supply 38 + ( 0.11*25 ) == 38 + 2.75 ≈ 41 Volts .

    And don't confuse Ump with Uoc , because Ump is important for feeding the battery ,

    while Uoc is important for the Charge Controller Udc max .

    Otherwise , Photowhit is right .

  • hmong2017hmong2017 Registered Users Posts: 39 ✭✭

    So if I use these solar panels and parallel them, I can charge a 24V solar system, right?

  • BB.BB. Super Moderators, Administrators Posts: 32,331 admin


    With solar power systems, the details matter:

    Maximum Power (Pmax):330 Watts

    Maximum Power Voltage (Vm):37.80 Volts

    Maximum Power Current (Im):8.73 Amps

    Open Circuit Voltage (Voc):46.20 Volts

    Short Circuit Current (Isc):9.33 Amps

    It also depends on the type of solar charge controller you pick (PWM is the less expensive type and MPPT is the more expensive/more capable type). where are located (Chico California?), size of battery system, size of solar array, etc...

    A "24 volt" solar panel for a PWM charge controller charging a 24 volt lead acid battery bank... Yes, your Vmp~35-40 VDC is the "standard" 24 volt panel running a PWM charge controller (or 2x 24 volt panels in series to charge a 48 VDC battery bank on a PWM controller).

    I would highly suggest that we backup a moment and we better understand your energy needs (how much power, where located, emergency backup, camping, etc.), what hardware you would like to use, etc.

    I don't want to give you the "right answer" to a relatively complex set of questions that can cause you more grief down the road.


    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.BB. Super Moderators, Administrators Posts: 32,331 admin

    I will close this thread.

    Here is a second thread with a lot more detail:


    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
This discussion has been closed.