Pls help me understand a current for MPPT charge controller

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • New_Climber
    Junior Member
    • Nov 2012
    • 18

    #1

    Pls help me understand a current for MPPT charge controller

    I was hoping you could help me understand what the “max battery current” rating is for a MPPT charge controller…

    I am looking at the Morningstar SunSaver 15 Amp MPPT Solar Charge Controller, I currently have 2-185w, 36v(44Voc) panels. I have not purchased any batteries as of yet.

    I am looking to have this system run some overhead LED or CFL A/C lights in a garage. So, I understand I will need a inverter also.

    My question mainly is, what and where does the 15amp part of this controller mean? Is it the current that the panels are producing? If I calculate the current (185w*2= 370w/36v) I can produce about 10amps at max production. If I decided to go with a 24v battery system, how does this factor in.

    In looking at any MPPT or even PVM charge controller, what does the current rating mean.

    Thx for the help…
  • Naptown
    Solar Fanatic
    • Feb 2011
    • 6880

    #2
    that is maximum current to the batteries.
    So you have 370 Watts maximum from the panels
    370/24= 15.1A
    You do lose about 5% so this should be all right. However there is no room for expansion.
    NABCEP certified Technical Sales Professional

    [URL="http://www.solarpaneltalk.com/showthread.php?5334-Solar-Off-Grid-Battery-Design"]http://www.solarpaneltalk.com/showth...Battery-Design[/URL]

    [URL]http://www.calculator.net/voltage-drop-calculator.html[/URL] (Voltage drop Calculator among others)

    [URL="http://www.gaisma.com"]www.gaisma.com[/URL]

    Comment

    • New_Climber
      Junior Member
      • Nov 2012
      • 18

      #3
      Originally posted by Naptown
      that is maximum current to the batteries.
      So you have 370 Watts maximum from the panels
      370/24= 15.1A
      You do lose about 5% so this should be all right. However there is no room for expansion.
      So when calculating the max current the charge controller can handle, the Voltage of the panels is not considered...just what the voltage of the battery setup. So in my situation, I could NOT use this controller if I was to use a 12v battery setup...is this correct? (370/12=30amps, to much for this charge controller)..

      Comment

      • Sunking
        Solar Fanatic
        • Feb 2010
        • 23301

        #4
        Originally posted by New_Climber
        So when calculating the max current the charge controller can handle, the Voltage of the panels is not considered...
        Not from the POV you are referring too. For MPPT controllers it is in reference to the output to the batteries.


        Originally posted by New_Climber
        just what the voltage of the battery setup. So in my situation, I could NOT use this controller if I was to use a 12v battery setup...is this correct? (370/12=30amps, to much for this charge controller)..
        Correct a 15 amp MPPT has a maximum power input of roughly 15 amps x 12 volts = 180 watts.
        MSEE, PE

        Comment

        Working...