rv solar

New install--I have a solarpro cc20 in my camper which specs state normal operating volts to be 12vdc. The controller array voltage (voc) can be upto 26v. My current array puts out 16.6v but will not pass through the controller to charge battery. I was thinking that the array side of the controller is bad. anyway to check this or is there a place I can go or send to have this checked. The 2 fuses are good. Thanks--daytona ,fl

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,439 admin
    Re: rv solar

    What are the voltages at the input and output sides of the charge controller under good sun light? (what brand of charge controller?)

    At the very least, if the battery needs charging, the controller should connect the solar array to the battery bank. If the controller is not doing this, then it may be bad.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SirSparks
    SirSparks Solar Expert Posts: 43
    Re: rv solar

    I can't help you better than Bill with that Q but I am in the process (almost done) of converting a box truck to RV with Solar array and solar hot water.
    A very intersting project I might be able to offer you some tips.

    I can add that my Outback Charge Controller shuts down before voltages are as low as 16 volts from the array.
  • System2
    System2 Posts: 6,290 admin
    Re: rv solar

    At good sunlight the array side of the controller reads 19v but of course the battery side is at 13.1 intil u draw off the battery and just goes down with no recharge. It must be a bad controller-It is a solarpro cc20 controller made by icp. Thanks
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: rv solar

    A couple of things that might help you out.
    First, the deep cycle battery FAQ's: http://www.windsun.com/Batteries/Battery_FAQ.htm

    Second, 16.6 Volts from an array is pretty minimal for trying to charge a 12 Volt system. It's just possible that between the wire losses and what the controller itself uses there's too low a Voltage left to charge the batteries properly. The 19 Volt reading you got is probably open circuit - meaning no load on the panels - which is irrelevant for charging purposes. Usually a 12 Volt system will have a panel Vmp of 17.5 to 18.5. You need to bring the batteries up to 14.2 to 14.8 Volts for proper charging.

    Third, if you want to check to see if the charge controller is malfunctioning, temporarily bypass it. Connect the panel wires directly to the battery wires and see if the battery Voltage comes up. Do not leave it like that! Without the controller in place you have to watch to make sure it doesn't go too high. If possible, put an Ammeter in-line on the positive wire and check the current flow as well. Be sure the meter can handle the total output of the panels.

    Some details you could supply that would help us determine what you should expect:
    Panel specifications including how many and what the Vmp, Voc, Imp, and Isc are. If you have the make and model we may be able to find that info on-line.
    Battery Amp hours @ the "20 hour" rate. Again if you have the make and model it may be possible to find out the capacity.
    If you don't have this sort of information it is very difficult to determine if anything is working properly.