Bafang BBSHD 48V battery problem.

[Grey-Beard]

Hi, I´m new to the forum, so go easy!?
Ok, I´ve just bought and fitted a BBSHD kit, it replaced a BBS02B 750W kit on the same bike.
I´m using a standard hailong/shark type battery, I have 2, a 12.5AH and a new 16AH.
The main issue is that the display shows the battery as flat, flashing, when the voltage is 46V.
The same display and battery on the 750W system was more than half full.
I´m concerned that there is an inbuilt low voltage cutoff in the firmware and it thinks that I have a 52v battery, as when the 48v is fully charged, 54.6V, the display shows 1 bar down from full.
I have the bafang programmer and lead. I also have the penov and M2.0 versions.
It shows
Model: BBS3
hardware version: V1.5
firmware: V1.0.0.4
voltage: 48-52 V
max current: 28 Amps

I have read a lot on here about flashing firmware, which i´m happy to do, but I would need to be pretty sure that it was going to work, no guarantee.
The numbers on the bottom of the motor don´t seem to be any help, CR R10E.1000. SN C571-30-506 2006032405.
I have an SW102 display and also a C965.

The 28 Amp limit makes it look to me like I have a newer version of firmware set for 52V, but the motor states that it is 48V and was sold as this.

Thanks for any help.

 

[fechter]

Use the Bafang config tool and see what the low battery protect voltage is set at.

 

[Grey-Beard]

Thanks for that, I have set the low voltage to 39V the same as I had for the 750W kit.
My concern is that the firmware must have upper and lower voltage settings, hence why the battery indicator is so far out.
Maybe ther is an older version of the frimware for a 48V battery with a 30A limit.

 

[Grey-Beard]

I feel a bit daft replying to myself, but here goes.
I have found an interesting list of Bafang BBS controller type numbers and the one that I have is listed as 52V.
Surely that would mess up the battery gauge on the display?

 

[fechter]

You are most likely correct. The Bafang firmware versions are a bit hard to figure out. I have the reverse problem on mine where the controller is 48v but I'm using a 52v battery so the battery gauge is always reading too high. While it may be possible to re-flash the firmware to fix the problem, you run the risk of bricking the controller in the process. Firmware versions also depend on hardware so not all versions will work with a given controller.

On one of mine I just gave up and installed a separate battery meter and I ignore the one on the Bafang display. It seems like there should be something in the display you can program for this but that's not how they did it.

 

[tomjasz]

Controllers can be "unbricked" with the correct firmware.