Solar Panel Wiring Voltage

Discussion in 'Off Grid Living' started by BenP, Mar 30, 2020.

  1. BenP

    BenP Monkey++ Site Supporter+

    When I installed our first set of solar panels I wired them parallel with around 34 volts going into my charge controller and 27 volts going into the batteries. It worked pretty well but I had a lot of wire running from the panels to the charge controllers. I recently bought bigger panels and decided to swap out one set of my originals with the new panels. I wired the new panels to be 125 volts going into the charge controller to reduce the amount of wire needed and to possible gain some efficiency. The 125 volt setup works well but the charge controller is now using the huge heat sink that it did not need before and it is warm to the touch. It seems like it might help the life of that charge controller if I rewire them to 65 volts.

    The panels are putting out about 1610 watts max.
    Charge controller is a Schneider Electric 60 amp 150 volt unit.
    Using THHN 10 gauge wire for panels.

    Edited: Charge controller is a 150v unit not 120v. @oil pan 4
    Last edited: Mar 30, 2020
    sec_monkey likes this.
  2. oil pan 4

    oil pan 4 Monkey+++

    You don't really want to push the upper limit of the max voltage.
    Having the voltage at maxpower output be around double battery voltage seems like a pretty good spot.
    Thunder5Ranch and sec_monkey like this.
  3. techsar

    techsar Monkey+++

    Yep, you need to back the voltage down from the panels...and you're pushing the amperage limit, too.

    1610w / 27v = 59.6a

    ETA: just looked thru the manual...150vdc open circuit, 140vdc operating...I guess they were looking for a cheap way to directly compete with
    Last edited: Mar 30, 2020
    Thunder5Ranch and sec_monkey like this.
  4. Cruisin Sloth

    Cruisin Sloth Special & Slow

    B4 we change anything we need panel specs , 24V system
    Im thinking 72 cell panels and you have them in strings of three to get that setup.
    I run Midnite classics CC . Your CC Hyper-VOC is 169Vdc ..
    What state are you in and how high are the panels as in altitude of sea datum

    Last edited: Apr 1, 2020
survivalmonkey SSL seal warrant canary