I have a Bafang BBSHD. My original 48v 16a battery died. I was told I could use a 52v battery and I could ignore the 07 error. When connected the display shows 07 error, which is an overvoltage error, but the motor does not power up. Is there anything I can do other than get a 48v battery?
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You can try lowering the voltage of the battery to below the 58.8v to 1v or 1.5v less then tell me what happens, even try JUST the 0.5v lowering see if that works.
That should work for you for the time being.
Have you installed new firmware? What year is the model BBSHD you have?
That should work for you for the time being.
Have you installed new firmware? What year is the model BBSHD you have?
How do I lower the voltage of the battery? How do I install new firmware?
I don't know the model. How do I find that out? I bought it in 2021.
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It might be easier just to get a new 52v version controller from lunacycle.com
@m@Robertson would know more about the firmware i believe.
m@Robertson
Well-known member
What @HumanPerson said for is the cheap solution, unfortunately. This is sort of an old issue and it comes from Bafang.
You can forget about firmware I'm afraid. There's no fix for this other than a new controller or bleed off some voltage. I did a quick google and here's a discussion from back in 2019 on the subject, which is about when Bafang sprang this pesky issue on the world.
Short version is you are screwed on 52v with this motor controller.
Late last year I bought a BBSHD from California Ebike (a vendor I still regard pretty highly despite their ownership change). I bought the 52v motor version. The way Cali Ebike fixes the 52v Bafang lockout is to flash the motor to allow a 14S pack, but to also limit the motor to 28a vs. the default of 30a. Trying to up the limit to 30a is refused by the motor's installed firmware. I prefer Luna motors since I like 52v and 30a to play together without any BS. The 28a limit is there to protect the HD's internals, which I have never found to be necessary, although I am sure there are people who find ways to break things and the 28a solution minimizes warranty and tech support.
As an aside, you asked how to lower the voltage of a battery. There are a few ways to do this and they all involve putting a load of some kind onto the system. I'll share the most successful one I have found:
To use it right, connect this device to the battery's output cable, which may already be the Anderson plugs found on the load resistor. To use it wrong like I do, plug it into the charge port and be damn sure you monitor it and disconnect at a safe lower level because you are bypassing the BMS' low voltage cutoff protection.
If you're not familiar with this device, what it does is suck electrical power directly from the battery. The device is essentially a heat sink, and the little SOB will get HOT... like 500 degrees fahrenheit hot after a few minutes, where it will stay until you unplug it. I set mine on a brick as if I put it directly on the garage floor it will scorch it. On a 52v pack it will deliver a continuous draw of, if I remember correctly, 7.5 amps. Thats equivalent to middling steady pedal assist so it won't hurt the battery to hook it up for the few minutes you will need to draw down a volt off the pack (I have two of these and can connect in parallel for a 15a load... don't get the bright idea to try that; its too much load imho).
You can also do yourself a big, fat favor and implement a limited charge regimen that only goes to 80 or 90%, with occasional monthly 100% balance charges drawn down by a device like this. You'll live with your existing hardware and help preserve battery life, pain-free. Here is the cheap way to get an adjustable, safe and reliable charger. there's a link there to a complete step by step how-to in the intro below that explains everything.
talesontwowheels.com
You can forget about firmware I'm afraid. There's no fix for this other than a new controller or bleed off some voltage. I did a quick google and here's a discussion from back in 2019 on the subject, which is about when Bafang sprang this pesky issue on the world.
Ask an ebike technical question get an answer within 30 minutes or so. - Electricbike.com Ebike Forum
Ok lets try this... Luna customers.... Do you have a fast question that is not specific to your order? Need a quick technical question answered? Please help us out by posting the question here instead of bogging down our email and phone support and we will do our best to speed answer your...
electricbike.com
Short version is you are screwed on 52v with this motor controller.
Late last year I bought a BBSHD from California Ebike (a vendor I still regard pretty highly despite their ownership change). I bought the 52v motor version. The way Cali Ebike fixes the 52v Bafang lockout is to flash the motor to allow a 14S pack, but to also limit the motor to 28a vs. the default of 30a. Trying to up the limit to 30a is refused by the motor's installed firmware. I prefer Luna motors since I like 52v and 30a to play together without any BS. The 28a limit is there to protect the HD's internals, which I have never found to be necessary, although I am sure there are people who find ways to break things and the 28a solution minimizes warranty and tech support.
As an aside, you asked how to lower the voltage of a battery. There are a few ways to do this and they all involve putting a load of some kind onto the system. I'll share the most successful one I have found:
To use it right, connect this device to the battery's output cable, which may already be the Anderson plugs found on the load resistor. To use it wrong like I do, plug it into the charge port and be damn sure you monitor it and disconnect at a safe lower level because you are bypassing the BMS' low voltage cutoff protection.
If you're not familiar with this device, what it does is suck electrical power directly from the battery. The device is essentially a heat sink, and the little SOB will get HOT... like 500 degrees fahrenheit hot after a few minutes, where it will stay until you unplug it. I set mine on a brick as if I put it directly on the garage floor it will scorch it. On a 52v pack it will deliver a continuous draw of, if I remember correctly, 7.5 amps. Thats equivalent to middling steady pedal assist so it won't hurt the battery to hook it up for the few minutes you will need to draw down a volt off the pack (I have two of these and can connect in parallel for a 15a load... don't get the bright idea to try that; its too much load imho).
You can also do yourself a big, fat favor and implement a limited charge regimen that only goes to 80 or 90%, with occasional monthly 100% balance charges drawn down by a device like this. You'll live with your existing hardware and help preserve battery life, pain-free. Here is the cheap way to get an adjustable, safe and reliable charger. there's a link there to a complete step by step how-to in the intro below that explains everything.
An Ultra Reliable Ebike Battery Charger…
How about a charger – quickly adjustable for voltage and current – that is rated for hundreds of thousands of hours of use before it typically fails?
talesontwowheels.com
I have managed to upgrade the firmware from 48v to 52v. I downloaded the software for free from California-Ebike.com (https://california-ebike.com/pages/updating-bafang-firmware). No more Error 7. It works a treat.
m@Robertson
Well-known member
Well damn. Thats new. Definitely something to file away for future reference.
I have heard from others that the 28a motors are gutless. Something in their output that is not fixable with the usual settings, and is in excess of the minimal 2a loss in peak power. Let us know your impressions of the motor after the flash. I'd appreciate an opinion as those reports were the real reason I set my Cali Ebike motor aside as a reserve instead of using it.
I have heard from others that the 28a motors are gutless. Something in their output that is not fixable with the usual settings, and is in excess of the minimal 2a loss in peak power. Let us know your impressions of the motor after the flash. I'd appreciate an opinion as those reports were the real reason I set my Cali Ebike motor aside as a reserve instead of using it.
