And that’s it’s one annoying thing and under the rubber black caps are tiny screws that need a long screwdriver. If u have the tool it’s easy. If u don’t have the tool u spend hours trying to make-do.
I highly recommend adding a wattmeter to it so u know what’s going on.
thanks
its got the right voltage when not connected (50.4v). when its charging it drops a little to 48v. is that normal? it shows 4amp as it should but then cuts out at some point. sometimes even at 60% then when I unplug and plug back in sometimes goes up to 80% are rarely to 90%.
got a wattmeter in between now to check. also bought the meanwell charger now but that doesnt charge at all, only shows the correct voltage. very strange…
To bulk charge a li ion battry you use a CC/CV
This means constant current then constant voltage
You battery’s drop voltage (pushing power of electrons) as thay discharge a 12s battry should be between 30v-50.4v
You bulk charger in the 1st stage should output its max ampage at a lower voltage depending on the battry it’s connected to the voltage will creep up over time as it charges up to the max voltage. In your case that’s 50.4v
Your bulk charger in 2nd stage once it reaches its max voltage will then reduce its current (A) slowly as it charges
3rd stage your bms will cut off the charge current once it hits the minimum threasholed
At some point during stage 2 and 3 possibly after you bms will bleed and possibly pause the bulk charging to lower any p groups to that have a higher voltage down to the same lvl as the lowest p group
60% 80% 90% were are these values coming from because there not a measurement that mean any thing to us as I described in the charging proses above. I can only presum thay are some calculated value from somewhere.
thanks, darkie. thats’s what i was wondering as well. i am taking the charge % from the vesc but how does the vesc actually know? in the first months of my battery it would actually charge up to 100% (according to vesc) and then stop.
regarding the charger charging stages, isn’t that rather the BMS regulating that? since the HLG-320H-48A is a LED power supply @hummie recommended it would not have such functionality?
thanks
sebastian
Yes it dose it’s a CC CV
What it dose not do is terminate the charge but the flexi bms can do that.
The VESC % is a calculation and it’s a known to be a bit off and not that consistent. It also depends on the VESC voltage limits that you set up.
Check the voltage it’s mutch more reliable. The discrepancy is the voltage dose not drop linearly it’s a curve every battry model has a difrent curve.
You also need to keep in mined that when you battry is in charge it is pulled up to a high voltage and when you disconnect the charger the battry will relax and rest so your voltage will drop a littl bit
The only way to know the battry is fully charged is when the current drops to nothing (even then it might just be the bms pausing the charge as it drains a pgroup that’s hit its limit befor it carys on charging)
If you have not been fully charging you battry I suspect you have never given enough time for you bms to finish balancing you cells. This can take several days for me to do this the first time on a new battry I build.
the vesc says 47.9v
78% charge
at this stage it stopped.
I’ll order a metr. and hope i can troubleshoot better with that. or unplug each pack and measure the voltage locally. i’ts modular luckily.
it just stoppes at some point. zero current.
the meanwell does charge my old battery with daly bms though.
@Darkie02 if balance wires are tightly bundled, is that only an issue in case the friction might damage the cables or is there some sort of interference happening when charging?
No just a higher risk that some thing shorts. You need to check all your p group voltages I’d exspect the charge is stoped because 1 of you p groups has a higher voltage than others and reaches the 4.25v cut off. That’s were I’d start to trouble shoot.
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I agree and if this is the case, the flexi should have a fault logged which can be found in terminal.
you mean it outputs too much voltage? didn’t realize that’s possible.
No as in if one of the cells in a p group becomes detached that p group charges faster than the rest until it hits it max voltage the BMS detects this and stops the charge.
Can’t rember of the top of my head if the flexi BMS has a max cell drift limit
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i finally managed to get the log from flexibms.
I also got the Meanwell charger working and updated the firmware on the Flexi.
BUT it still stops charging while the vesc says 48v pack voltage and 80% charge.
Do these reads look healthy to you? can’t work out what’s wrong as to me they all seem relatively even. Thanks Seb
State:4038:4023:4035:3987:4038:4036:4038:4036:3991:4030:4038:4012:47691-47691-47710:0-0-0:0-0-0:305:312:0:notCharging:
State:4038:4023:4036:3987:4036:4036:4038:4036:3991:4030:4038:4012:47691-47691-47710:0-0-0:0-0-0:305:313:0:notCharging:
State:4038:4023:4035:3987:4038:4036:4038:4036:3991:4030:4038:4012:47691-47691-47710:0-0-0:0-0-0:305:312:0:notCharging:
State:4038:4023:4035:3988:4036:4036:4038:4035:3991:4030:4038:4012:47691-47710-47710:0-0-0:0-0-0:305:313:0:notCharging:
switchin charger on here!
State:4039:4024:4036:3988:4038:4038:4039:4038:3993:4032:4039:4014:47691-47710-48674:0-49273-50177:0-0-9141:305:313:0:chargingEnd-cell3TermVoltage:
State:4038:4024:4036:3987:4038:4036:4038:4036:3991:4030:4038:4012:47691-47710-47710:49112-49433-49453:0-0-0:305:313:0:chargingEnd-cell3TermVoltage:
State:4038:4024:4036:3987:4036:4036:4038:4036:3991:4030:4038:4012:47691-47710-47710:49413-49433-49433:0-0-0:305:313:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4036:3988:4038:4036:4038:4036:3991:4030:4038:4012:47691-47710-47710:49413-49413-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4036:3987:4036:4036:4038:4035:3991:4030:4038:4012:47691-47691-47710:49393-49413-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4035:3988:4036:4036:4038:4035:3991:4030:4038:4012:47691-47710-47710:49393-49413-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4036:3987:4038:4036:4038:4035:3991:4030:4038:4012:47691-47691-47710:49393-49413-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4024:4036:3987:4036:4036:4038:4035:3991:4030:4038:4012:47691-47710-47710:49393-49413-49433:0-0-0:305:313:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4035:3987:4036:4036:4038:4035:3991:4030:4038:4012:47671-47691-47730:49393-49433-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4036:3987:4038:4036:4038:4035:3991:4030:4038:4012:47691-47710-47730:49393-49413-49453:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4035:3987:4036:4036:4038:4035:3991:4030:4038:4014:47671-47710-47730:49393-49413-49453:0-0-0:305:313:0:chargingEnd-cell3TermVoltage:
Fault count:
Latched faults:
State:4038:4023:4036:3987:4036:4036:4038:4036:3991:4030:4038:4012:47691-47691-47730:49393-49413-49453:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4035:3987:4036:4036:4038:4036:3991:4030:4038:4012:47691-47691-47710:49393-49433-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
State:4038:4023:4035:3987:4036:4036:4038:4035:3991:4030:4038:4012:47691-47691-47710:49393-49413-49433:0-0-0:305:312:0:chargingEnd-cell3TermVoltage:
it seems to me as if all parameters are still normal but for some reason cell 3 stops it to charge. but the voltage is the same as and below the limit.
it also barely enters balancing mode. it sometime does but not for a long time. i switched always balancing on now.
@SimosMCmuffin would need to look at it because it’s contradicting to the readings as fare as I can tell.
Settings to change that
cheers! I also got the new charger to work. I had to raise the allowed amperage which was on 6500 by default.
HLG320-48 can output 6.7A so yes up the charge current ( parameter $1) a little or turn down the Current a little on the PSU.
FlexBMS gets quite warm over 8A but is rated for 10A I believe I just keep it under 8A personally
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Got my flexi bms installed. Everything works. Setting up through serial was easy. Instructions where good, Only complain was lack of information on CANbus connection and how to make it work with robogochi/metr.at . After quick consultation turns out you have to connect all the lines (CAN-H CAN-L GND 5v) to any of the ESC’s and do CAN forward to robogochi in vesc tool.