I have a phoneix 12 1200 that under high load starts to cut out. I have considered the bms but that stays on and the 12 volt circuits remain powered during the inverter cutting out. I have a smart shunt and the voltage doesn't drop lower than 12.8 volts on trends. I have read the low voltage cut out is preset at 10.5 volts. Can anyone shine any light on it? The load is 1100-1150 Watts and is on for around 2 -3 minutes, cutting out after about 1 1/2 minutes.