Let it charge, it’ll balance over a few hours (after the charger shows green). If that doesn’t help, time to wonder if that thing works at all or you wired it correctly
I personally would try to get things as close as possible before hooking it up, just because the balance function of most BMSs is pretty slow.
And there are some that just flat out refuse to work if your pack is too out of whack to start.
Best to give the poor thing a fighting chance IMO.
Another dumb question I had - and this one is just curiosity - if I had a 12s battery and hooked just 4 of the balance leads to a 4s balance charger would that balance those groups?
When does a charger “go green”
When it has been disconnected by the BMS?
when it has been disconnected?
when it has disconnected by itself hitting a current threshold?
when it has disconnected itself by hitting a voltage threshhold?
What does this mean for balance charging?
does the BMS start draining high cells without stopping charging. in which case it’s balancing when the charge light is red.
does the BMS stop the charger when a cell hits full turning the light green, and continue draining high cells until it turns the charger on again and the lred light goes on again? I’ve never seen that but i’ve never paid close enough attention.
I wonder how accurate the statement. “when it turns green it’s done charging, and it’s done balancing charging”. which i’ve seen on the net many times
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I thought this was the case too. I kinda just accepted it and hoped my board/charger did everything right. It’s why I’m also buying a fire extinguisher
It depends on the balance charger.
Most generic RC balance chargers require the main leads to be connected as well as the balance leads for the balancing to work, but if you were to hook those up too (not to the pack’s main discharge leads, but to the start and end of the four cells you want to balance), then yes it will work because the charger doesn’t care what’s hanging off either end, just what’s between the leads.
One other caveat though: The above only works if those four cells are one unbroken string, E.G. groups 6, 7, 8, and 9. If for example it’s groups 4,5,7, and 9, then it won’t work and may damage your charger.
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It depends on the BMS. Some begin balancing once the average cell voltage reaches a set level like 4.0V, while charging. Others won’t until a cell reaches 4.20V, and/or the overvoltage cutoff (4.22 or whatever), and will stop charging, drain that cell back down, then begin charging again.
There’s a good chance that option two will happen even on a BMS that can do option one, simply because charging is so much faster than balancing, so you may easily reach OVC on a cell before the balancing is finished.
It also depends on the charger; Some will turn green when their current drops to some small fraction of the maximum current (like 100mA or whatever), where others will turn green as soon as they reach their threshold voltage regardless of current. Some will keep “float charging” the battery once they turn green always supplying power, where others will shut off entirely once they reach green, and won’t turn back on until the voltage on the output drops a few points. All these different behaviors can affect how the BMS behaves too.
A good rule of thumb IMO is to leave your pack plugged in and green for a couple hours, and then check your cell voltages (assuming this is a new/untested/unbalanced setup), to see if things have gotten better. If so, keep going. If not, start digging into why they haven’t gotten better.
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that’s a pretty big “it depends”. but confirms my suspicions that it wasn’t so cut and dry either.
thanks.
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My charger turns green and stops the fan as soon as the daly bms reads 50.4v out of the pack. Bms seems to get warm some while before and keep warm for some time after (bms sits on one vesc. That one reads like 44°, the other 40-42°) so from what i can read here, my bms balances from when it’s almost charged, all the way untill all cells reach 4.20V.
Charger doesn’t turn on unless the pack had a overvolted cell, the bms shut off, drained the cell and resumed full speed charging. That is usually pretty distinct with the charger turning on and off often. Means something’s wrong
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Hello!
Who makes the “best” Vesc based controller these days? Single vesc not dual.
It’s highly likely this is plastic insulated instead of silicone insulated. If that gets hot enough to melt the plastic you will have big problems.
If you use a large enough gauge to never get that hot it might be okay, 14AWG would be too small for me to feel safe.
Also even huge wire like 10AWG it could still melt near the ends where the connectors are.
Really you want silicone-insulated wire.
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Weeell… the vesc, from @Trampa developed by vedder himself. All others are based on the original design to some degree, or majorly different but with some key design points that make it compatible with vesc firmware
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Yeah probably the best vesc but pricy as fuck.Specially if you need 2…
Is Faradaymotion still around? They worked with Veddar himself at the beginning of Vesc era. I have 3 F.day vesc. All of them are solid and still works, except I fucked up the can chip[s] years ago…
Hmm. There’s a dude in Holland I think who did sell some solid e skate stuff. I just can’t remember his name…
Well, there are all kinds of derivates out there at all price points. With most of them you get what you pay for
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Indeed.
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Thinl I found what I was looking for.
I haven’t tried one but heard those aren’t bad units. They seem like unobtainium though.
The Torqueboards ESCs (the new version 6 ones) are pretty good, though I don’t quite think they are for sale yet, but should be extremely soon I think
Please don’t buy those, that’s old hardware and ridiculously overpriced/
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Might be… ah shit forgot about TB vesc. They habe a very good reputation. Atleast to “old” version…
I thought they stopped making those at some point few years ago.?
As long as hardware goes. 4.12 is all I need for this build. And ~280€ for 2pcs. Is that overpriced in todays standards?
Do you have any recommendations?