Daly 4s 12V 100A BMS not restarting

[newsolardude]

Recently set up a new system and got my battery/BMS system working just fine (Voltmeter on +battery terminal and PV- read 13V, was able to use inverter and briefly charge with PV load). Something tripped the BMS, I disconnected all loads to it and voltmeter on +battery and - battery read 12.4V. However, voltmeter on +battery and P- reads 8.66V only. I googled and tried to reset the BMS by touching the P- and B-, but voltmeter on +battery and P- continues to reads 8.66V. What else can I do? Thanks!

 

[newsolardude]

Actually, I left the BMS alone and rechecked it after a hour and now the BMS is working (voltmeter on +battery and P- reads 12.4V). I assume it needed time to reset? Not quite sure why though. I'm trying to figure out why the BMS shorted:

I was able to run an AC unit on just the batteries last night for a few hours. This morning, I connected the PV (53V, 8Amp) to my MPPT and I'm thinking that perhaps the system isn't able to handle charging and discharging?

The system currently is:

2 210watt panels (connected in series to give 53V, 8amp)
Makeskyblue 60A 12V MPPT
Krieger 1100 Watt 12V
4s 3.2V 210Ah cells with the Daly 4s 12V 100A BMS

Load is only a small window AC unit. that draws at most 600Watts.

 

[mikefitz]

12.4 volts seems a near dischargec battery, my guess is that low cell volts ( whilst on load) activated low volt protection in the bms. The cell recovered to 'recovery volts' and the BMS allowed correct operation. It's possible charging would have caused recovery.

Mike