I’ve read a few places that MPPT charge controllers can be damaged when a BMS goes into rapid shutdown (to protect the battery) and am trying to understand the issue:
During nighttime (solar off) if the BMS goes into Low Voltage Disconnect, the MPPT was not charging and so it should be fine, correct?
During daytime while MPPT is charging, if the battery reaches High Voltage Disconnect, the charge controller should be in Float so little/no current should be flowing so again, MPPT should be fine, correct?
During daytime while the MPPT Charger is charging, in general it shouldn’t be possible to trigger Low Voltage Disconnect while MPPT is charging and most inverters can be set to shut down based on SOC or low voltage before LVD is triggered, so it seems like the MPPT has little to worry about in that case as well, right?
So is it only in the case of a failing battery and one cell quickly rising up to trigger OverVoltage Disconnect before the overall battery is close to being charged and while significant charge currents are flowing out of the MPPT that damage can occur?
I’m struggling to understand the scenarios where BMS can damage MPPT, the mechanism whereby an MPPT charge controller can be damaged, and the easiest/cheapest design alternatives to protect against such damage.
During nighttime (solar off) if the BMS goes into Low Voltage Disconnect, the MPPT was not charging and so it should be fine, correct?
During daytime while MPPT is charging, if the battery reaches High Voltage Disconnect, the charge controller should be in Float so little/no current should be flowing so again, MPPT should be fine, correct?
During daytime while the MPPT Charger is charging, in general it shouldn’t be possible to trigger Low Voltage Disconnect while MPPT is charging and most inverters can be set to shut down based on SOC or low voltage before LVD is triggered, so it seems like the MPPT has little to worry about in that case as well, right?
So is it only in the case of a failing battery and one cell quickly rising up to trigger OverVoltage Disconnect before the overall battery is close to being charged and while significant charge currents are flowing out of the MPPT that damage can occur?
I’m struggling to understand the scenarios where BMS can damage MPPT, the mechanism whereby an MPPT charge controller can be damaged, and the easiest/cheapest design alternatives to protect against such damage.