JBD BMS Issue

[azeus17]

I hooked everything up on my new 72v motorcycle build tonight in an attempt to do the auto learn and some fine tuning. However, as soon as I give any throttle input, the BMS clicks and cuts out instantly. The sprocket on the motor gets maybe two revolutions. I am using a JBD AP21S002 on a home built 72v battery connected to a Fardriver controller. Controller is set to 100A max line rate and there is no load on the motor, so it should not be pulling anywhere near that. When the BMS cuts out, it does not record anything (no undervolt, overvolt, etc.) but the controller does give an undervolt error briefly before resetting. After about 5 seconds, the BMS will try again, but cut off just as quickly. Does anyone have a suggestion? I've attached screenshots of my BMS settings as well. All 20 cell voltages are currently 3.7XX.

I should also note, this BMS was purchased from BatteryHookUp.com. I originally ordered for lithium ion, but they were sold out and offered the LiFePo4 version. It was originally set up for a LiFePo4 battery, but I updated all the voltages for lithium ion. It is entirely possible I missed something.

 

[A-DamW]

Looks like you are using the Overkill solar app?

Maybe just as a test, bypass the bms and see if you get the same behavior.

 

[dominik h]

Why does jbd offer Lifepo and Liion Version?
I have installed both versions from jbd, but I never tried to change from one to another chemistry by changing settings. are you shure this is even possible?

During my 500A Tests with the JK-B2A-24S BMS
Link
I had the same issues.
The BMS was used before for Li-Ion and I changed the values to fit my lifepo pack for the test. The BMS always cut off, until I changed the preset to Lifepo.

 

[azeus17]

Looks like you are using the Overkill solar app?

Maybe just as a test, bypass the bms and see if you get the same behavior.

Correct, Overkill app. It seems much easier to use, but there is no option, as far as I can tell, to select battery chemistry, so I had to update all settings myself. Not a huge deal, but I would no be surprised if I fat fingered something, especially when they are all in mV and mA.

Good idea to bypass the BMS for a test. I’ll have to lengthen my ground temporarily, but no big deal.

 

[dominik h]

Jbd does not have selectable presets. They sell two versions.

 

[azeus17]

I know they don’t have selectable presets, but you can update all the setting to whatever you want, which is what I did and what batteryhookup recommended.

It is definitely the BMS. I bypassed it and motor ran as expected.

 

[dominik h]

The same I had done with the JK-B2A-24S BMS and it did not work. It worked when I changed the preset to Lifepo and put in the same values as before.
There must be a reason why they sell two versions.

 

[Portugaline]

What is the version of this JBD bms? I had a similar problem with a JBD bms with relay.

 

[A-DamW]

Probably going to be a process of elimination.

I would start with disabling the three NTC's you have enabled, then test.
Next, one at a time, set the Trig. Delay for
Charge over/under
Discharge over/under
Batt over/under
Cell over/under
to something like 15sec and see if the motor runs for longer

At some point, with enough patience and methodology we can figure out what is triggering shutdown.

 

[eee291]

You can use the xiaoxang app to apply a lipo or lifepo4 preset. I usually do the light preset and then make a few more tweaks to balancing turn on voltage and precision and it's good to go.

Are you sure that if you swipe down in the home tab that it doesn't show a number of protection events like cell under voltage 5 times or something similar?

I know it worked for me. I used a "lipo" jbd BMS on a 16s lifepo4 battery.
It had a cell with very high resistance, It would cut out like you described but it stayed on and it reported like 25 cell undervoltage events.

 

[azeus17]

Thank you everyone for the input. Unfortunately, I did not have anymore time to mess around with the JBD as this project has a deadline of Aug. 26. I ordered and installed a JK BMS. What a difference. Not only in function (the fact that it worked, like I expected), but size as well! The JK is about 1/3rd the size of the JBD. I have no idea why that is, but it is much better for my build, so it was kind of a win both ways. I'll keep the JBD for another project. Maybe I'll build a battery bank for my trailer...who knows.