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Daly (?) 200a 12v 4s Smart BMS (with Bluetooth) from Ali...

Yes, those were the first things I did too. And I thought to try 123456 too, and it worked. Thank you ?

For some reason it's letting me change various parameters but when I try to set a change on the 'sum volt high protect', it won't change it (from 14.6 to 14.5) no matter how many times I press the set button. Weird. But anyway, I'm very curious what the best advice is on the other parameters as well.
Yes, some things appear to be computed by values in other settings, and others you just can't change (at least from Bluetooth, I haven't tried the PC software which apparently can set more things). A lot of the other settings are "whatever you are comfortable with".
 
For example, what's the ideal discharge temperature range? And the maximum current for charge / discharge?
For maximum charge and discharge, I put 140 amps, just because I'm currently not testing above that, and that is the recommended .5C rate.
My temperature range in Phoenix might be a bit different from what you want to use. I told mine not to discharge over 45°C, but only because I plan on keeping mine in air conditioned environment, otherwise that is a common high temperature here during the summer.
 
Thank you. I've also noticed that the BMS seems to deactivate and no longer show up in the Bluetooth app after it sits for a while. That I have to short the two wires again to make it pop up again. Is this only happening because it's not currently charging / discharging? I hope so, because I clearly don't want to have to short it back into gear several times a day...
 
Thank you. I've also noticed that the BMS seems to deactivate and no longer show up in the Bluetooth app after it sits for a while. That I have to short the two wires again to make it pop up again. Is this only happening because it's not currently charging / discharging? I hope so, because I clearly don't want to have to short it back into gear several times a day...
Another Daly BMS I purchased for 24V operation has a "light board" with a pushbutton that seems to accomplish this. I know others have reported a timeout setting you can change, I assume it defaults to not staying active to reduce power consumption when idle. You could also just connect a switch to be able to just push a button to wake it up as well. My 24V Daly's don't have the pins to even short out, I think Daly is doing themselves a disservice by having too many different models, making it unnecessarily difficult. I also set the charging current limit to 120 amps, since the label says 125 amp max charge rate. One would think they might include something documenting this with the BMS rather than depending on you to find the spec sheet.
 
Thank you. I've also noticed that the BMS seems to deactivate and no longer show up in the Bluetooth app after it sits for a while. That I have to short the two wires again to make it pop up again. Is this only happening because it's not currently charging / discharging? I hope so, because I clearly don't want to have to short it back into gear several times a day...
 
Change your sleep timer from 3600, to 15300. That is supposed to cancel the BT sleep. Since I did that, BT stays on and app connects every time. As for changing total pack voltage, I don't think that can be changed, as the total pack voltage is the sum of the High cell V x #cells, or Low cell V x #cells. Change the Low cell V to 2.75 and see if total pack V changes to 11V
 
Thank you! What about these other settings?
 

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OK guys... I've been on the move and unable/wary to fully charge the battery overnight anywhere in MX. However I just finally got my battery isolator unit set up and connected to it from my van, and I'm about to drive a few hours which should be long enough to finish fully charging the battery. My intention has been to do so, then disconnect the cells and connecting in parallel to let them sit to balance each other overnight. What I'm curious about at this point is whether that's entirely necessary, or if this BMS will effectively balance the cells.... it would be nice to not have to take everything back apart now that I finally got it all working, lol. Thoughts?
 
OK guys... I've been on the move and unable/wary to fully charge the battery overnight anywhere in MX. However I just finally got my battery isolator unit set up and connected to it from my van, and I'm about to drive a few hours which should be long enough to finish fully charging the battery. My intention has been to do so, then disconnect the cells and connecting in parallel to let them sit to balance each other overnight. What I'm curious about at this point is whether that's entirely necessary, or if this BMS will effectively balance the cells.... it would be nice to not have to take everything back apart now that I finally got it all working, lol. Thoughts?
The Daly spec sheet says 35 milliamps balance current. Depending on how out of balance your cells are, it could take a LONG time for the BMS to actually balance them. I would definitely recommend doing a top balance to the cells before using them as a pack. Your mileage may vary, but my cells arrived with very significant SOC values. Some required as little as 5ah to get to full, others required 160ah to get full, all measured at 3.3xx volts when they arrived, or less than 10 millivolts difference.

At 35 milliamps balance current, you could be talking about 6 months or more, depending on the balance settings you use, and number of charge cycles. Don't depend on the BMS to do an initial balance, it's not designed for that.
 
One problem I'm having is that the BMS is telling me it's 100% charged already, even though I know it's not. So I'm not even sure how fully charged it actually is as a pack right now. the isolator connected it's been getting 30 to 40 amps of continuous charge while I've been driving, and I have about 3 hours of driving left to do today. I was really hoping it would charge fully so that I could rearrange the cells in parallel to sit overnight tonight. I kind of need that to happen actually. I'm guessing that once it's fully charged the BMS app won't show active current(?)... if I'm right then hopefully the current will drop to zero at some point before I get where I'm going.

But if it doesn't... can you help me understand why the cells need to be fully charged in order for the balancing thing to work?
 

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I guess I mean, is it possible to do the parallel Balancing Act if they are mostly charged, but not fully charged?
 
One problem I'm having is that the BMS is telling me it's 100% charged already, even though I know it's not. So I'm not even sure how fully charged it actually is as a pack right now. the isolator connected it's been getting 30 to 40 amps of continuous charge while I've been driving, and I have about 3 hours of driving left to do today. I was really hoping it would charge fully so that I could rearrange the cells in parallel to sit overnight tonight. I kind of need that to happen actually. I'm guessing that once it's fully charged the BMS app won't show active current(?)... if I'm right then hopefully the current will drop to zero at some point before I get where I'm going.

But if it doesn't... can you help me understand why the cells need to be fully charged in order for the balancing thing to work?
Let's put the numbers in perspective. 35 milliamps current to balance 280,000 milliamps of battery capacity. Now do you understand?
 
I guess I mean, is it possible to do the parallel Balancing Act if they are mostly charged, but not fully charged?
To do a proper top balance, all the cells must be completely full.

The Daly BMS is wildy inaccurate in calculating SOC, as you have noticed. Cell voltage really doesn't diverge until above 3.4 or 3.45 volts, so telling the BMS to start balancing below that is useless. I will also point out that the Daly reports numbers that are not accurate as to current flow as well.
 
I mean if one of the cells is, say, 50 amp hours more full than the others, then the BMS will stop the charge on all of them when the fullest one hits the top. Right? Then if they are disconnected and rearranged in parallel, they balance each other out. But that is seeing as effective top balancing when the other three weren't full anyway. So why can't they be balanced in parallel at any state of charge? I'm clearly new to all this and unclear on some of these details. Thanks for the input.

Also, I've been noticing that the little toggle switch and the BMS app that says balance likes to be off a lot but doesn't respond when I press on it. I have seen it on at least once though.
 
I mean if one of the cells is, say, 50 amp hours more full than the others, then the BMS will stop the charge on all of them when the fullest one hits the top. Right? Then if they are disconnected and rearranged in parallel, they balance each other out. But that is seeing as effective top balancing when the other three weren't full anyway. So why can't they be balanced in parallel at any state of charge? I'm clearly new to all this and unclear on some of these details. Thanks for the input.

Also, I've been noticing that the little toggle switch and the BMS app that says balance likes to be off a lot but doesn't respond when I press on it. I have seen it on at least once though.
Look at a charge and discharge curve for any LiFePO4 cell, the reason why it must be a top or bottom balance will be obvious. Bottom balance is more common in electric vehicles, top balance is your usual objective for normal use. Cell voltage really only diverges at the extremes, matching voltage between 3 and 3.4v is pretty useless, and there can be big divergence in state of charge.

The cell balance is resistive type of very little capacity. What that means, is that it works by slightly retarding the charge of a single cell by 35 milliamps. Most people only want it working on charging, rather than having it burn off the charge when you are nearly empty. It really only does anything at the extreme ends. You can change those settings in the app.
 
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What I'm confused about is this. Right now, because one of my cells (cell #1) has had a higher voltage than the rest of them ( and probably a higher state of charge as well), my BMS is now cutting off the charge to all of them because cell #1 Is topping off. But you said they all need to be full in order to properly top balance them. So what about the other three? If it's cutting off charge because of the first cell, then that means the other three aren't reaching full charge. So how can I properly top balance them if that is the case?
 

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What I'm confused about is this. Right now, because one of my cells (cell #1) has had a higher voltage than the rest of them ( and probably a higher state of charge as well), my BMS is now cutting off the charge to all of them because cell #1 Is topping off. But you said they all need to be full in order to properly top balance them. So what about the other three? If it's cutting off charge because of the first cell, then that means the other three aren't reaching full charge. So how can I properly top balance them if that is the case?
Er, maybe read the sticky post labeled "Top Balancing 'How to'"?
 
Since one of them actually got full, it seems prudent to do the overnight parallel connection to let them balance now. But Will that work? Or will it not be a proper top balance because the other three cells aren't As fully charged? if the latter is the case, then it seems a bit like saying that you can't properly balance your cells until they're already balanced, which is a catch-22. Or maybe I'm misunderstanding. Which is likely, lol.
 
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