Post #9410

Never a dull moment... Last night the new solar system guy called and said his lights went out at 27% battery. He goes out to the mech room and finds one battery with breaker off and the other 3 are at 0% SOC. I assumed that there was some error in the capacity of the batteries and those 3 batteries had shut themselves down one at a time and the last man standing could not support the load of the house by himself. This was not the case. We used ferrules over the stranded wire going into these breakers on the battery.... the wire pulled out of the ferrule and got hot. As you can see it tripped the breaker. This caused one battery (25%) to drop off the group. Now we're down 25% on the SOC calculation. The other three batteries carried the system until they were depleted. I added another layer of logic to the connect to the grid to charge batteries scheme... If SOC is <25% charge batteries OR if the voltage is <47.8v, charge the batteries from grid. We keep learning.