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CA_Traveler's avatar
CA_Traveler
Explorer III
Feb 11, 2015

MS SS-10L Solar Controller and New Batteries

We're replacing the 2 12V batteries in my sons 5er with 2 GC2 batteries, 232AH. The solar setup is 2 80W panels at 9.4A total. The current controller is a MS SS-10L. The manual indicates that this controller is a constant voltage controller at 14.4V. Apparently no float voltage and this concerns me since the rig is stored for months at at time with plenty of sun available.

Am I over concerned about this controller and should it be replaced along with the new batteries? I could ask my son to turn off the solar when stored but prefer a more seamless operation.

If replacement is called for then with which one? We don't want to spend to much as there may be a future solar update that would require another controller at that point.

6 Replies

  • Still consider the sealed battery setting for lower storage voltage and no equalization.
  • smkettner wrote:
    Must be an old SS-10L as the new data sheet says four stage charging.
    Can you set it to sealed battery to get lower voltage?
    Watch the water level... especially as it warms up.

    So I guess I would recommend a new SS-10L or jump to the next level depending on expanding the system.
    Oops I was looking at the wrong manual! :o

    OK Controller is good.
  • Isc is 4.97 and flat mounted panels so I'm not concerned about the 10A controller rating.

    The controller is mounted in a storage area and as I understand it the Solar30 is positive ground meaning 12V on the case and then yes I'd be concerned and a full ventilated cover would be required. But a solar upgrade is in the future...
  • Must be an old SS-10L as the new data sheet says four stage charging.
    Can you set it to sealed battery to get lower voltage?
    Watch the water level... especially as it warms up.

    So I guess I would recommend a new SS-10L or jump to the next level depending on expanding the system.
  • 14.4 is too low for when camping and too high for when not camping.

    http://pdf.wholesalesolar.com/battery-folder/charging_instruction_2011_2.pdf

    Poly 80w panels have Isc of 5.1 approx. So expected amps at STC would be 10.2. You should have 1.25 x that in the controller for some margin when panels do above their rating, so the controller will not overheat. So a 15amp is the next size up.

    However to get an adjustable voltage up to 15v, more amps for future expansion, and a nice readout display as well, IMO the one to get is the Solar30 for about $35 on eBay. I have one and it is very good. (no need for concerns about that grounding business)
  • Hi Ca,

    I don't think there is much concern. After all the sun goes down every night--so the charging stops.

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