Announcement

Collapse
No announcement yet.

sizing up mppt controller againts panels

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • sizing up mppt controller againts panels

    Hello all,
    is there a formula on how to get the correct mppt controller for panels like these?

    e.g 250watts

    Maximum Power (Pmax): 120W
    Voltage at Pmax (Vmp): 17.4V
    Current at Pmax (Imp): 6.91A
    Open-circuit voltage (Voc): 22.0V
    Short circuit current (Isc): 7.28A

    Thanks sa mag susuggest or mag help

  • #2
    If it is a real MPPT controller Amps = Watts / Battery Voltage.
    MSEE, PE

    Comment


    • #3
      Originally posted by sunnyday View Post
      Hello all,
      is there a formula on how to get the correct mppt controller for panels like these?

      e.g 250watts

      Maximum Power (Pmax): 120W
      Voltage at Pmax (Vmp): 17.4V
      Current at Pmax (Imp): 6.91A
      Open-circuit voltage (Voc): 22.0V
      Short circuit current (Isc): 7.28A

      Thanks sa mag susuggest or mag help
      Hello again Sunking, i dont understand. so there are others that are not so 'real' MPPT's controllers out there?

      also i wanted to connect 2 250w panels with same specs as above. should it be parallel with 24v of batteries?

      thanks sir

      Comment


      • #4
        there are many "knockoff" boxes from disreputable mfrs, that have a couple o junk parts inside, a blinky LED, and a sticker on the outside that says MPPT. junk inside.
        Powerfab top of pole PV mount (2) | 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

        Comment


        • #5
          Originally posted by sunnyday View Post
          Hello again Sunking, i dont understand. so there are others that are not so 'real' MPPT's controllers out there?

          also i wanted to connect 2 250w panels with same specs as above. should it be parallel with 24v of batteries?

          thanks sir
          Whatever battery voltage you want makes no difference. 500 watts / 12 volts = 41.6 amps, or 500 watts / 24 volts = 20.8 amps. Take your pick.

          You run panel voltage as high as possible with MPPT, so in your example they would be in series regardless of battery of voltage assuming you choose a MPPT with a high enough Voc input. There are controllers that can input up to 600 volts and run a 12 volt battery.
          MSEE, PE

          Comment


          • #6
            Originally posted by Sunking View Post
            Whatever battery voltage you want makes no difference. 500 watts / 12 volts = 41.6 amps, or 500 watts / 24 volts = 20.8 amps. Take your pick.

            You run panel voltage as high as possible with MPPT, so in your example they would be in series regardless of battery of voltage assuming you choose a MPPT with a high enough Voc input. There are controllers that can input up to 600 volts and run a 12 volt battery.
            is this the spec i should be looking for?

            Max. PV input power=12V 130W; 24V 260W

            Thank you for the replies

            Comment


            • #7
              Originally posted by sunnyday View Post
              is this the spec i should be looking for?

              Max. PV input power=12V 130W; 24V 260W

              Thank you for the replies

              or this?

              Max PV input power 12V 520W; 24V 1040W

              Comment


              • #8
                Originally posted by sunnyday View Post
                or this?

                Max PV input power 12V 520W; 24V 1040W
                No that only tells us the controller is 40 amps. What is the Voc input of the controller?
                MSEE, PE

                Comment


                • #9
                  Originally posted by Sunking View Post
                  No that only tells us the controller is 40 amps. What is the Voc input of the controller?
                  is this the correct info?
                  Max.PV open circuit voltage = 100VDC

                  http://www.epsolarpv.com/en/index.ph.../444/am_id/136

                  that link is the actual product that i am trying to consider as its the only one available right now besides their 60a which is twice the price.

                  Comment


                  • #10
                    Originally posted by sunnyday View Post
                    is this the correct info?
                    Max.PV open circuit voltage = 100VDC

                    http://www.epsolarpv.com/en/index.ph.../444/am_id/136

                    that link is the actual product that i am trying to consider as its the only one available right now besides their 60a which is twice the price.
                    I am not familiar with this product but I see a big RED FLAG.

                    Tracer is an advanced Maximum Power Point Tracking MPPT controller. ·4-Stage charge with PWM output


                    Which is it? MPPT OR PWM?
                    MSEE, PE

                    Comment


                    • #11
                      Originally posted by Sunking View Post
                      I am not familiar with this product but I see a big RED FLAG.



                      Which is it? MPPT OR PWM?
                      well yes ofcourse its made in china . but closest that i can get as shipping isnt really an option. (local gov't taxes us with twice the price of the bought items)
                      i have seen a lot of guys using this locally so im assuming they ok. they confirmed its mppt too.

                      Comment


                      • #12
                        Per someone in this thread , http://www.solarpaneltalk.com/showth...ge-Controllers , MPPT tech is on the panel side of the CC, but they still send power to the batteries via PWM (except when in bulk mode).

                        Someone else on that other thread has a Tracer 4210 ; He said it is good, but he is upgrading to an outback because he wants more features.

                        Comment


                        • #13
                          Originally posted by s2man View Post
                          Per someone in this thread , http://www.solarpaneltalk.com/showth...ge-Controllers , MPPT tech is on the panel side of the CC, but they still send power to the batteries via PWM (except when in bulk mode).

                          Someone else on that other thread has a Tracer 4210 ; He said it is good, but he is upgrading to an outback because he wants more features.
                          I had a tracer 3215. I recently upgraded to a midnite classic 150. I run 3 panels in series, and saw an improvement, but it wasn't mind blowing how much better it did. The tracer works, it is very slow in tracking, but it does work and finds the max power point. The features of the midnite are just so much better, and worth every dollar.

                          Comment

                          Working...
                          X