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Jk bms with 280ah cells not behaving correctly.

ddonq1412

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I am looking for some assistance with a jk bms to Solis hybrid inverter. I had hooked this up only yesterday morning using cells out of a seplos mason pack. Was hoping the BMS could balance cells and charge them to full. The BMS I was using is a 2nd hand unit so values were pre configured. I was giving settings to apply. The Solis inverter is set up to acid lead battery type as everything else give can fail.
 

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Umm I see a cell delta of .003v at cell voltages of around 3.425, that’s pretty much perfect in my book.

I don’t see the problem.
 
At present it's saying the battery is empty at that voltage so I have a bad setting somewhere
 
The remaining battery Ah and % will be meaningless until you have done a full charge and cycled the battery a couple of times.
 
Ok how do I get my inverter to see that voltage . As it shows low battery and the inverter cut out last night.
 
At present it's saying the battery is empty at that voltage so I have a bad setting somewhere
See that calibration voltage of 54.8v on the third image, try dropping that to 54.75 and see what happens.
 
Ok how do I get my inverter to see that voltage . As it shows low battery and the inverter cut out last night.
That’s an inverter issue, review the settings of the inverter, if it was programmed for acid I’m surprised it was thinking it was low voltage.

Is there any link between BMS and inverter?
 
What size cables and what was the load the inverter was trying to provide?
 
BMS to switch and then to fuse is running on. 50mm cable and then it's drops down to 25 mm cable that came with the inverter. The load would be around 2kw
 
BMS says "Discharge On", so it should be allowing power to flow.

Use a Volt Meter (Multi-Meter), and read the voltage at:
1) Battery + to BMS B-
2) Battery + to BMS C-
3) Both Sides of Fuse to BMS C-
4) Fuse Output to both sides of Shunt (if you have one)
5) Fuse Output to Inverter Battery -
6) Inverter Battery + to Inverter Battery -

They should all read about 54.8v. If any don't then that is where to look.
Basically, all along the wires, you should be seeing 54.8v to the Inverter. If the + and - at the Inverter reads 54.8v, then you have a problem with the Inverter (battery breaker on the inverter turned on?).

"No link just power cables between them."
Don't worry about what the Inverter says is the SOC. You want to know what the Inverter sees as Voltage. If it sees more than 48v, it should be happy.
 
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The cycle count is crazy if he had only recently hooked it up. 109 days running, 2300 cycles that’s 21 cycles a day if I read his data correctly. I’m thinking a bad connection in the balance harness likely to the most positive red (power lead) or the black lead. Something turning it on and off a lot. Go into the system log (three dots in upper right of app) and see all the events.
 
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I have cut the wires to try and get it to fit on to seplos mason box and PCB boards.
 
The cycle count is crazy if he had only recently hooked it up. 109 days running, 2300 cycles that’s 21 cycles a day if I read his data correctly. I’m thinking a bad connection in the balance harness likely to the most positive red (power lead) or the black lead. Something turning it on and off a lot. Go into the system log (three dots in upper right of app) and see all the events.
Something is very wrong. The cycle count can't be right as the cycle capacity doesn't match. This would be a huge figure of 2300x280Ah. It's on 78ah. Faulty BMS?
 
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