@JTAG Danny thanks for that - good to know that SOC is indication only
Still having trouble keeping BMS charging above 40V
current condition with charging off is
45V charging voltage
V Pack = 40.93V
CVHigh = 4.110
CVLow = 4.096
Condition Status-- Power Down""
Have Charger enable threshold set to 0.50A
Cell Hard Overvoltage set to 4.35V
Cell Soft Overvoltage set to 4.20V
Charge hysteresis set to 0.01V
Is there any way the power switch can be changed to a latched switch to keep BMS charging
What current do you use for charging? What kind of charger is it? Could you try powering it up with the button and then apply the charger?
@rpasichnyk hahaha it is fighting you I see . It does seem a bit like a re power loop indeed. Good thing is that it will eventually power down. I will try to recreate it and build a delay mechanism to prevent this oscillation. What ESCâs do you have dual/single? Or do you know the total capacity?
@JTAG I am using a DPS5015 CCCV charging module set to 45V 5A
without charger or usb connected and the balance wires connected - when the pack voltage is applied - pushing power push-button switches it on and the switch led comes on for 5 seconds and then it goes off and BMS goes to Power Down mode .
Its as if it is waiting for something during that 5 seconds. Pushing the power pushbutton after the five seconds does not switch is back on again and it stays in Power down mode.
Well the reason why it is unable to stay on by itself is one of the reasons why it wonât charge. Ill pm you and we will dive into this. Later when it is resolve ill share the reason back here.
You probably mean V0.20 ? Yes that one should support it. Can you enable it the regular way by use of the push button?
I kick the wheel with my foot, you should spin the motor quite a bit but it should work! Does the power led on the BMS turn on when you quickly turn the wheel (this should happen)? The same should happen on the VESC itself.
First of all. I made stupid mistake by slipping out postive battery lead out of my hands while connecting.
Argghhh I was so carefull all the time, by double checking, measuring etc.
However it made very short contact with GND pin of the canbus transceiver creating a tiny spark.
There is no visual damage to the traces or components as far as I can see.
If I look at the schematics there are no components in the lowest resistance path during the short circuit so maybe nothing is damaged.
Now the issue.
I can only power up the bms by re-connecting usb
The bms keeps in power down state, so starting up, showing eventually message âbyeâ
In the real time tab there is not fault
however temperatures of the bms is fluctuating to minus values
What I did
Iâam able to connect to the diebiems tool.
Update firmware to 0.20
Execute bootloader_jump via terminal
Read default config
Adjust battery pack to 12S
Write to BMS and save to flash
Reboot by disconnecting usb cable
When I re-connect the display shows V0.15 or V0.17 ( donât remember, unable to check) instead of V0.20 in the tool.
If I read the config in the tool after rebooting. It shows the change to 12S and V0.20
I know there is big mismatch in the cell, I need to check if this is really the case, Battery is completely new.
It was balanced couple weeks ago.
Also updated drivers, disabled temp setting etc. to get it out of the power down state.
amazing work! I just came across this post (sadly after I have already purchased a BMS). This is amazing. A lot of it went over my head but from what I understood, it is amazing.
When I get some funds I will have to upgrade my BMS to this model.
I have a few questions.
Is there a way without plugging in the USB to change settings to balance the pack at ~3.7v for storage when the board wonât be used over the winter period? Can this be done over CAN with bluetooth plugged into a VESC?
Currently that functionality is not there (yet), maybe in the future. On the shorter term I will implement a mechanism for the balance resistors to function as regenerative bleed resistor in combination with a buffer capacity of the battery (to go downhill for long even trough it was just charged).
The desired discharge to storage voltage has close ties to this functionality, that might be added quickly after that.
@Samau18 has a 3rd batch group buy going on now. you can get in on it as early as now as it seems like getting to the target of 50 orders is taking a while anyway. just in case you were interested
That would be really good. It would add a lot of safety to the board to be able to brake as soon as you jump on it. Keep up the great work.
How do we Tip you for your great work? As when I purchase one I will definitely have to spend a few extra dollars towards the brains behind it.
Also how is that additional piece going for the 250amp model? I would of loved if it was expandable to 16s with the huge currant draw option as my brother wants me to electrify his quad bike and I was planning to go 16s with a 250 amp ESC on a 7-9kw (maybe 13kw if budget allows) motor. I can definitely see there is no huge need for it with esk8 though as it would just make it bulkier for no good reason.
Once the GB is finalized and production is started a portion of all payment goes to @JTAG for all the effort Heâs put in and continues to put into this awesome project