joeyoliver
New Member
My off-grid system is comprised of 3x EG4 LifePower4 48V batteries connected to an EG4 18KPV hybrid inverter with a 4KW solar array. I'm using the system to run the power at an off-grid cabin including a 240V well-pump. The AC output of the inverter is connected to a breaker box with a 50A main breaker and several smaller breakers.
This system has been working as expected for the last several months - no issues, running the well pump and the power and with the batteries rarely dipping below 75% Soc. Yesterday I noticed that one of the batteries was showing 0% Soc and was flashing an alarm light. The other two batteries were still on 75-100% Soc.
I removed the affected battery from the bank, rebooted the system and turned on the AC output breakers. After a few seconds I saw that the next battery in the bank was now showing 0% Soc and an alarm fault light. Thinking the problem was with the well pump I tried again with the breaker for the pump off and this had the same effect with the final battery in the system (I know that this wasn't a smart thing to do...). None of the breakers for the house flipped and there were no alarms on the inverter and on inspection there was no obvious damage to the wiring from the batteries to the inverter.
When I view the battery diagnostics of the batteries using the BMS test app on my computer I see the SOC at 0% and the 'Low SOC' alarm (I don't think there's a way to access any historical data). I've attached a picture of the BMS Test battery info page.
Because this only happened when there was a load on the system it feels like the fault must be upstream of the battery bank, but no breakers flipped in the house so it feels like the fault might be downstream of the house wiring.
- Is there anything that could cause this kind of discharge to occur except for a short-circuit?
- Could there have been an internal fault in the inverter causing the battery bank to short circuit?
Any help or guidance would be appreciated.
This system has been working as expected for the last several months - no issues, running the well pump and the power and with the batteries rarely dipping below 75% Soc. Yesterday I noticed that one of the batteries was showing 0% Soc and was flashing an alarm light. The other two batteries were still on 75-100% Soc.
I removed the affected battery from the bank, rebooted the system and turned on the AC output breakers. After a few seconds I saw that the next battery in the bank was now showing 0% Soc and an alarm fault light. Thinking the problem was with the well pump I tried again with the breaker for the pump off and this had the same effect with the final battery in the system (I know that this wasn't a smart thing to do...). None of the breakers for the house flipped and there were no alarms on the inverter and on inspection there was no obvious damage to the wiring from the batteries to the inverter.
When I view the battery diagnostics of the batteries using the BMS test app on my computer I see the SOC at 0% and the 'Low SOC' alarm (I don't think there's a way to access any historical data). I've attached a picture of the BMS Test battery info page.
Because this only happened when there was a load on the system it feels like the fault must be upstream of the battery bank, but no breakers flipped in the house so it feels like the fault might be downstream of the house wiring.
- Is there anything that could cause this kind of discharge to occur except for a short-circuit?
- Could there have been an internal fault in the inverter causing the battery bank to short circuit?
Any help or guidance would be appreciated.
