Load MOS short issue

AdmiralJason
AdmiralJason Registered Users Posts: 4
I have an Epever 4210-AN controller and seemingly at random it generates this error. I have the load terminals turned off in the configuration but this error keeps coming up. Does anyone know where I should look to fix this error? I've cleared the error off the screen and I've disconnected the inverter from the battery to let the panels charge the battery back up. It was sitting at 11.7 volts when the error occurred. I don't have an accurate SOC for you, I'm waiting for another meter and shunt to come in. Here's the screenshot of the MT50 remote though:


Any help would be greatly appreciated!

BTW the rest of the system contains 2 100w panels in parallel totalling no more than 16A. The battery is a LiFePo4 100ah. 
Thanks.
Tagged:

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Welcome to the forum AdmiralJason,

    I could find no reference to MOS error...

    First question... 12.0 volts on a charging lead acid battery and 11.7 volts is approaching an automatic load cutoff voltage (typically 11.5 volts down to 10.5 volts depending on setup)... at 11.5 volts under load, you are (very roughly) looking at a battery that is 50% discharged or lower (10.5 volts is "dead").

    My first concern would be to get your battery bank charged... Depending on battery type/chemistry, typically in the range of 14.2 volts to 14.8 volts held for 2-6 hours to get battery bank fully charged.

    So--My first guess is that the MOS error may be tied to your low battery voltage... And in any case, you need to get your battery quickly recharged or it will "sulfate" and die.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • AdmiralJason
    AdmiralJason Registered Users Posts: 4
    Hi Bill, thanks for the reply. The battery chemistry is lithium iron phosphate. If it is a low voltage issue, I imagine I'll have to add another battery in order to increase the longevity between the panels charging it back up. Would I need more panels in order to get 2 batteries topped up enough during the day to supply power through the night then?
  • AdmiralJason
    AdmiralJason Registered Users Posts: 4
    Oh, I also forgot to mention that I did find out what "load MOS short" refers to. Apparently when the load MOSFET is shorted, it will generate this error. It doesn't give anymore information than that though
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    If the load wires are not shorted together (need to be "floating" separate if unused)--Then sounds like a problem with the charge controller.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • AdmiralJason
    AdmiralJason Registered Users Posts: 4
    Hi Bill,
    I was afraid of that! It was my first thought but I was hoping it was something else. Thanks for your help with this though!

    AJ