Most reacted posts

That's very kind, but if you do fix it, perhaps I'll send you the other broken one and you can keep it if you choose to return the one you fixed. I am interested in how it failed and if you fix it, you can keep it or trade it for my other broken one.

Sounds good, I'll work on that when I get the stuff to build a new harness, or buy one. Soon!

Just FYI, I have been to Finland. Spent a few nights in Jyvaskyla (don't know if that is how to spell it correctly).

No.

The two times that the BMS failed, I believe the inverter shut down first (I wasn't at the house, my kids were taking care of it - supposedly).

I think you are correct. Something is wrong with cell 9 and I could be repairing forever unless I deal with that problem.

Just one 280 AH LifePO4 with 16 cells in series.

If it is due to the inverter tripping first, perhaps I can adjust the discharge current on the BMS to make sure it trips first?

Just FYI since I am on my third and last JK BMS, I did reduce the balancing current from 2A to 1.5A. So far it is working, but who knows why? I have a manual transfer switch from the grid to pure solar power. I have been careful to make sure that the inverter is up and running before making...

Thanks for that. I'll still send you one if you want to see it. As I said, I am on my third one and need to figure out how to stop this from happening again.

I set it to 3.45V. I had it there originally, but things were failing so I tried a lower balance. It didn't help, so we are back to 3.45V. We'll see. I may have to improve my soldering skills. I have many multimeters. Power supply went bad, but at the moment I am charging the battery...

I have another thought. The 16 cells are connected in two groups of 8 each. Within each bank of 8, they are connected by bus bars, but the two banks are connected by a cable. Would that make a difference because cell 9 is the first one in the second bank and cell 8 has also gone bad twice...

That's what I thought. It is burning up the balance resistors even if I lower the balance current. Cell 9 is always involved. The other cells are close by. I have been through 3 JK BMS units and they all have the same issue so perhaps the arrangement is a problem or cell 9 itself is...

I may have to consider fuses if I cannot figure out why the balance resistors are getting fried.

Are you saying that the Victron Chargers don't actually hold the voltage settings?

What if I swapped it to a different position? Never mind, that was a stupid thought on my part.

Thank you so much. I mentioned that we manually transfer between the grid and solar a few times a week. I have made a few modifications to the transfer process and have reduced the balancing current. Looks good so far! I also noticed when I was running the full 2A balance that there were...

I agree with you in general, but these are wires, and crimps - essentially, they are resistors. The interesting thing is that the common failure on both of them (cell 9) has the best connectivity. So I wondered if that was a problem if there was some kind of surge when the inverter shut down...

I am on my third B2A24S20P. They seem to run great for a while, but the first two both failed with the error being "CELL COUNT DOES NOT MATCH SETTINGS" I have a 16S 48V 280 AH battery. It is not the wiring, been all through that and besides, it runs fine for a while but once the error comes...

Thank you!

Yes, it seems so. I am thinking that it is the interaction with the inverter, but we'll see. I do like the unit when it works! It is the inverter tripping that I think is the problem, not the BMS.

It is V 4.81. Here is the screenshot . . . from the working unit. I am not the best at soldering, but hey, I've got two units to practice on.

Thanks for that link. I did check the leads (or so I thought) because it seemed to be the reasonable thing to do. I will check them again but that still begs the question as to why a new unit works with no change to the leads at all.

No hissing sound.

Yes, I am using the same harness. I will order or make a new one to check that, but the third BMS is working fine on that same harness.

Is it possible that the leads have to be within a certain tolerance of each other or some of the balance electronics gets fried? It is a bit suspicious that cell 9 is on both failed units and the two cells on either side also failed on one and then the other.

Not sure what you mean. But I do use an older android phone to monitor and adjust the settings using the built-in bluetooth capability of the BMS. The inverter is a standalone and I cannot change those settings. I purchased the inverter because it can provide split-phase AC that is needed in...

How are things going? My third BMS is still working with the reduced balancing current.

Thanks so much to upnorthandpersonal for his help. I could hardly express how thankful I am to him. But as many have pointed out, there must be something causing the problems in my 16S configuration with this JK BMS. Cell number 9 was always involved. And believe it or not, a week or so...

Thanks again, no, I am not using it. Perhaps I should go into my issues with the inverter or at least provide the info on it.