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_DJ_1's avatar
_DJ_1
Explorer II
Mar 11, 2016

Solar question

I have 100 watt system with a Morning Star controller on my TC. I was thinking of getting a portable 100 watt suitcase type with it's own built in controller by Renogy that I could use on a lot of other things too. But a guy told me that I can't use it with my current system on the TC as it will mess up the controllers. Any truth to that? Thanks............DJ

16 Replies

  • You can edit quoted posts.. no need to repost the entire thing to respond to a single line.
  • dcg9381 wrote:
    What's a "TC"?

    TC=Truck Camper, just as TT = Travel Trailer, 5er = Fifth Wheel Camper.

    2oldman: Happy now?
  • DJ,
    What's a "TC"?
    I think you're asking if two solar systems will interfere with each other (two solar controllers).

    If that's the question, the answer is yes, at least potentially.
    Solar controllers work by reading what the battery is doing. When you add two controllers, the voltage at the battery is artificially inflated by one and the other may misread that as battery charge level.

    In practicality, it'd be hard to tell exactly what's going to happen - it's going to depend on controller type.

    I have a remote power station at a gate. It's charged by both a small battery charger and a solar array.. The array and charger definitely interact.

    What can you do about it? In theory, you can add diodes to the charge side of the controller so it's not possible to feed back any current through the less powerful controller. This would make sure you at least don't get a loss. I'm not sure that it solves the issue.

    Best solution would be to isolate a battery for charging with the portable setup.. IE - one charger hits one set of batteries, the other charger on the others. While isolated, the RV couldn't use that batteries under charge.

    Best suggestion would be to get a charge controller that handles both arrays and arrange a way to plug in the portable setup to that controller. Solar arrays arranged in parallel.
  • I've heard tales of the two controllers fighting, but that's about all I know about it. The link above probably has all the answers about dual controllers

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