Replacement for C30A

Hi, I have solar on a remote cabin in the mountains of Colorado that will never be on a grid. I have had 15 years of perfect service out of my Trace SW4024, Trace C30A charge controller, and my 12 massive Western Electric 210 amp 2volt batteries. BUT now my batteries do NOT fully charge - only to 23.6 volts. I checked each solar panel and each 12 volt panel is still putting out 17+ volts as they always have with a total 35+ volts. I then checked the Trace C30A charge controller. The slow blinking led indicates a good steady charge, but the high level limit was at 23.6 volts. For 15 years it has been at 25.0 volts. I got out the manual and adjusted it back to 25.0 volts, but then closed up the cabin.

Should I replace the Trace C30A charge controller now that I am having trouble with it? What should I replace it with? Also, is Trace Engineering still in business?

Thanks Ron


  • BB.
    BB. Super Moderators, Administrators Posts: 33,477 admin
    Re: Replacement for C30A

    Trace is now Xantrex--And still in business (although, they recently sold part of the Solar RE business to Schneider Electric and everything is shaking out now).

    And you can still purchase the CXX family controllers.

    Otherwise, MorningStar also makes PWM and some very nice (and expensive) MPPT type charge controllers.

    You probably would be happy with any of them. A Remote Battery Temperature Sensor is always a recommended option (most controllers will actually use a slightly lower charging voltage with their "internal temp sensor" (self heating of the controller). A RBTS is virtually required for the MorningStar MPPT 15 amp controller.

    Regarding your charging voltage... ~27.2 volts would seem to be a better "float voltage" and 28.8 volts for Bulk/Absorb charging.

    25 volts seems way to low (may not ever fully charge a battery bank) unless you have something from the battery manufacturer that says to use this reduced voltage.

    Are these Sealed or Flooded Cell type batteries? Sealed battery do not like high charging voltages (>~28.4 volts) or equalization (>30 volts).

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Replacement for C30A

    i'm guessing that after 15 years of service that the cells may be on their way out and need replacing. allow the cells to rest for 3 hours or more and check the voltage of each cell. if you get like 2.1v, 1.9v, 2.0v etc then a good eq charge may be needed. also i assume the electrolyte is at a good level. if the voltage readings are like 2.1v, 2.2v, .8v, etc. then the .8v is out of bounds and most likely a bad cell. this is only an example of what to generally look for as a cell could actually reverse its voltage too.
  • System2
    System2 Posts: 6,290 admin
    Re: Replacement for C30A

    Thanks so much Niel, I will check each battery when I go back out to the Cabin. I have read alot today on New controllers. I just ordered the Zantrex C40. I will check the high charge limit to make sure it is 27.5 volts or so. I hope that it auto-selects the 24 volt system and auto-selects the high charge limit. Ron