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MPP 24V Solar Inverter Troubleshooting

The BMS was working so I’m definitely not purposely charging without it. It’s connected but I don’t know why it’s not working anymore. The power supply is about to stop charging the batteries and I’m repeatedly monitoring as well.

Thank you for the link, I will check it out.
I would contact Overkill and send them the screenshot with all the cells reading 0.1v, they have a good warranty.
The question is do they have one in stock.

Edit to add, you really do NOT want to charge without a BMS. You WILL ruin the battery cells. Trust me on this.
 
You should not charge without a BMS, you will soon ruin your batteries.

Yes, it certainly looks like the BMS has been fried. The BMS looks at individual cells that make up the battery and protects (shuts off) if an individual cell would be damaged by more charge or discharge. If all of the individual cells are above 3.0v and below 3.5v, I would stop charging until you replace the BMS. The cells that make up the battery have a charge curve that is interesting, and makes it very difficult to control manually, that's why everyone uses a BMS.

Identical BMS (I think):


One that is actually rated high enough to run your Multiplus:


Never mind, I looked back, you have a 2000 watt inverter, the 100 amp model is fine. You may wish to contact Overkill, they have a good warranty.
Got it, thank you!
 
Got it, thank you!
I have great news, my BMS is working! I reviewed my overkill manual on how to calibrate it and it’s back working! I see that one of my batteries is over voltage while the others have drained since I top balanced them days ago. I have questions on what to do next as I’m currently connected in series. It’s not showing in this clip but the over voltage protect alarm has been triggered as well because of cell 5.

Should I discharge the one battery to get it under 3.6v and if so how?

Should I put them back in parallel for top balancing since most have dropped a few volts? One thing I don’t understand here is how that keeps the one that’s over voltage from staying over voltage?
 

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I have great news, my BMS is working! I reviewed my overkill manual on how to calibrate it and it’s back working! I see that one of my batteries is over voltage while the others have drained since I top balanced them days ago. I have questions on what to do next as I’m currently connected in series.

Should I discharge the one battery to get it under 3.6v and if so how?

Should I put them back in parallel for top balancing since most have dropped a few volts? One thing I don’t understand here is how that keeps the one that’s over voltage from staying over voltage?
Put a load on right away. That's close to the range the electrolyte will start to boil and puff out the cell. The good news, it won't take much of a load for a short time to bring it down. Turn off the charger.
 
Put a load on right away. That's close to the range the electrolyte will start to boil and puff out the cell. The good news, it won't take much of a load for a short time to bring it down. Turn off the charger.
Okay. I just need to see how to do that. I understand it, I just don’t know how to do it fully so let me find a video really quick unless you have a suggestion?
 
Turn on the inverter and plug something in.
So I would assume I can’t get the inverter to come on because of the over voltage protect alarm. It does work, I tested it momentarily by plugging it up directly to the battery a week ago. But everything is wired correctly now with the BMS in between.

What would my other option be to add a load? The BMS is balancing it, it’s just doing it very slowly
 
So I would assume I can’t get the inverter to come on because of the over voltage protect alarm. It does work, I tested it momentarily by plugging it up directly to the battery a week ago. But everything is wired correctly now with the BMS in between.

What would my other option be to add a load? The BMS is balancing it, it’s just doing it very slowly
Plot twist, the voltmeter reading for that battery is 3.39 so something is off from my calibration I believe. Let me see if I can fix that.
 
Great news to end this thread, the voltage recalibration allowed the over voltage alarm to go away, the inverter kicked on and I have all my power back!!

Thank you to everyone who helped me from day one starting a few weeks ago knowing nothing about this system till now!

This forum rocks @Will Prowse!!

huge thank you to @Just John! You’ve answered every single question I’ve had and you exhibited great patience with me from being a total newbie!
 
Great news to end this thread, the voltage recalibration allowed the over voltage alarm to go away, the inverter kicked on and I have all my power back!!

Thank you to everyone who helped me from day one starting a few weeks ago knowing nothing about this system till now!

This forum rocks @Will Prowse!!

huge thank you to @Just John! You’ve answered every single question I’ve had and you exhibited great patience with me from being a total newbie!
Sorry, I had to step out and babysit my granddaughter. Glad you fixed it, not too shabby for a "newby". :)
 
Great news to end this thread, the voltage recalibration allowed the over voltage alarm to go away, the inverter kicked on and I have all my power back!!

Thank you to everyone who helped me from day one starting a few weeks ago knowing nothing about this system till now!

This forum rocks @Will Prowse!!

huge thank you to @Just John! You’ve answered every single question I’ve had and you exhibited great patience with me from being a total newbie!
You did good for a newbie. How are your batteries doing?
 
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