Forum Discussion

eend's avatar
eend
Explorer
Jul 30, 2022

Battery over charging.

I have 2 100 watt solar panels on my roof, and a Zamp solar controller which came standard with the trailer.

On the display it shows that the battery is sitting at 16 volt, when the sun is out and charging and I can hear the battery hissing.
I always thought that that the controller holds it at 12- 14 volt.

Does this mean that my controller is pooched?

With this over charging at 16 volt, my inverter won’t work either.
  • eend's avatar
    eend
    Explorer
    Jul 31, 2022
    2112 wrote:
    Ed_Gee wrote:
    Voltage will rise as the plates become exposed to air...
    Current will rise but not voltage while using a properly functioning controller. The controller should hold its 13.x to 14.x set point voltage up to its current limit regardless of battery condition. The voltage will decrease once the current limit is reached.

    eend - Is this the same battery you said was toast or did you buy a new battery? My guess is your bad controller toasted the old battery.


    I took the bad battery back to Costco last week and got a full refund and I bought a brand new one back.

    But I did order a new controller yesterday so it should be here today according to my friends at Amazon.
  • 2112's avatar
    2112
    Explorer II
    Jul 31, 2022
    Ed_Gee wrote:
    Voltage will rise as the plates become exposed to air...
    Current will rise but not voltage while using a properly functioning controller. The controller should hold its 13.x to 14.x set point voltage up to its current limit regardless of battery condition. The voltage will decrease once the current limit is reached.

    eend - Is this the same battery you said was toast or did you buy a new battery? My guess is your bad controller toasted the old battery.
  • 3_tons's avatar
    3_tons
    Explorer III
    Jul 31, 2022
    “On the display it shows that the battery is sitting at 16 volt”…

    Not saying it is incorrect (??), but it’s no substitute for a decent shunt-based meter - makes such validation (and much more like SOC, amps, history, etc…) a snap…:)…BTW, if the controller is bad you might consider upgrading to a MPPT type controller to further exploit harvest…

    3 tons
  • Ed_Gee's avatar
    Ed_Gee
    Explorer II
    Jul 31, 2022
    If your battery is a wet cell, have you checked the electrolyte levels lately? Voltage will rise as the plates become exposed to air... and battery will get hot and hiss as more electrolyte is gassed off.
  • time2roll's avatar
    time2roll
    Nomad
    Jul 30, 2022
    Verify with a separate voltmeter. Otherwise need to disconnect solar asap and look for a new controller.
  • 2oldman's avatar
    2oldman
    Explorer II
    Jul 30, 2022
    Unless your Zamp is in 'equalize' mode, it's malfunctioning.

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