Bafang BBSHD Over Voltage Protection issue on 52v

[Japtastic]

Hi,

Just finished installing my BBSHD kit with 52v 17.5ah battery. First ride went very well as the battery came around 80% charged.

I then charged the battery to 100% / 58.8v and the colour screen instantly shows the error:

Error Code:07
High Voltage Protection

I had to plug in my phone and leave the screen on to discharge for a couple of hours to bring it down to 57.3v. Then it worked just fine.

The seller responded with the below message. I've asked what the 'complier' is and a wiring diagram but no reply yet. What is this complier likely to be? Sounds like a tweaked version of the firmware for 58.8v is not on there. Pretty frustrating!

It doesn't matter, this is the error code for the battery voltage is too high.

I communicate with bafang engineer.
There have two solution:
1.You can send me the controller back to me and I returned to the bafang to change to 52V.
2.I can send you a Compiler and you should Rewriting to 52v by yourself.
Best regards

 

[john61ct]

The battery itself has no need to get to 100%.

Determine exactly what the high cutoff is, and keep resting V target just below. A small controlled discharge load removing "surface charge" may also do the trick.

This will give a bit of greater longevity to the bank as well.

Just isolate from the discharge side if you need to go high, e.g. doing a top balance.

____
Another option, reduce the bank's number in series.

 

[TommyCat]

It seems from what I've been reading that Bafang has let out a bunch of controllers such as yours that do not allow operation at 52v full charge capacity. Generally it's been excepted that with a 48 volt controller you can step up to 52 volts nominal with no problem.
This has not been the case with these. Some resellers such as Luna has caught this in advance, and took corrective action for their customers. Although that action has been kept some what of a secret.
From your supplier's reply I would speculate that it has to do with re-flashing the firmware. If you are successful at getting your controller to work with 52 volts nominal you would be a HERO! And a very popular and sought after person. :lol:


Best of luck,
T.C.

 

[Japtastic]

Thanks chaps. Bit of a pain having to keep an eye on voltages and pull it at the right time or charging to 100% and then discharge with a load.

Will see what they come back with when they reply.

 

[john61ct]

Your charger isn't adjustable?

An adjustable HVC could disconnect its input. . .

 

[amberwolf]

The battery itself has no need to get to 100%.

If it has a common BMS like almost every ebike pack out there, then yes, it does, in order to do it's balancing. That only occurs once the cells reach balancing voltage, which is usually only at top of charge, at HVC.

If the battery is made of good quality cells that are matched and tested, this doesn't really matter, as they wont' get out of balance easily.

But most common ebike batteries (not the OEM bigname bikes, but probably even some of those) are NOT made of good quality cells, and are NOT matched and tested, so they DO get out of balance easily, and the battery has to be fully charged in order to fix this.

If you don't ever fully charge it, it'll get further and further out of balance, appearing to lose more and more capacity, and performing worse and worse each ride. How quickly this happens depends on the actual quality of the cells, and how poorly matched they really are, and how hard they are pushed each ride (how much current is pulled vs their specs, how hot they get, how far they are discharged, etc), and how old they are.

It is of course possible to charge it fully only occasionally, just to do the balancing--this is the point of those chargers with switchable final voltage (like the 80-90-100% settings, or the Satiator that you can set anything you like in the profiles).


But...the base answer is still:

Yes, a common ebike battery DOES have to be fully charged in order to operate the way it was designed and built.




So you have to think about all the possible ramifications of your answers to questions before you post them--for instance:

If a noob reads your answer quoted above, that basically implies they never have to fully charge their battery, then they may be quite disappointed as their battery performs worse and worse, and they may even waste hundreds of dollars and throw it away and buy a new one, when all they really had to do was plug it in and let it sit on the charger for long enough to finish balancing (which by that point coudl take days or even weeks, but it will usually still fix it).

 

[amberwolf]

Your charger isn't adjustable?

An adjustable HVC could disconnect its input. . .

FWIW, the two ideas above are for different things.

The charger adjustment can be done on some of them, but most are not. (at least, not in a way a typical person will be able to easily do).


The HVC is in the BMS, not the charger. These are rarely adjustable, in common ebike batteries (it's becoming less rare from certain companies that cater specifically to the DIY crowd, like EM3EV and Luna, but if you randomly pick one from a list on a google search it's unlikely to be adjustable in any way). Sure, you can buy a BMS that is programmable, either via USB, serial, or BT...but then you have to take your battery apart, take out the old one, and replace it with the new one. Not something the typical person will want to do, even if they could do it safely.


So, yes, either of those things would fix this issue...but it would be much better to fix the firmware of the BBS controller. Then the full capacity of the battery can be used, in a regular everyday fashion, without worrying about it's balance state, etc.

 

[amberwolf]

The seller responded with the below message. I've asked what the 'complier' is and a wiring diagram but no reply yet. What is this complier likely to be? Sounds like a tweaked version of the firmware for 58.8v is not on there.

It doesn't matter, this is the error code for the battery voltage is too high.

I communicate with bafang engineer.
There have two solution:
1.You can send me the controller back to me and I returned to the bafang to change to 52V.
2.I can send you a Compiler and you should Rewriting to 52v by yourself.

Basically it's just a firmware update; he'll need to send you a programming cable (USB to the BBS programming connector) as well. Generally this is easy to do for most kinds of FW updates, but Iv'e never done a BBS unit. Most things I've updated FW on all you have to do is plug the cable into the device and the computer, run the program on your computer, and it sees the cable (as a serial port usually), then it sees the device, and asks if you want to update the firmware. Choose yes, and wait, when it's doen it tells you, then you disconnect everything and go back to using the device. Exact steps will depend on device, so you ahve to ask them for those exact and complete steps before you do anything. There *is* always the risk of bricking the controller...but it's generally low, and you can aks the seller if he will still replace it if that happens since it would be, at root, his fault it happened.

If he'll pay for shipping both ways, and you can afford the loss of time being without it, then sending it to him would be the "easiest" option.


Regarding wiring diagrams...unless you need it to hook up the BBS to the rest of the bike, then you shouldn't need any kind of wiring diagram for anything.

 

[Japtastic]

Perfect, thanks for the help chaps. I was imaging having to take the controller out to solder on to particular pins to flash new firmware.

I’m more than happy to plug in a USB to flash the new firmware to resolve the issue rather than wait a month to send it to China and back.

I’d rather charge to 100% most of the time. I opened the pack to check the cells as soon as I got it and it does confirm what they wrote on AliExpress and matches the description of the Samsung 35E pink cells.

 

[john61ct]

The battery itself has no need to get to 100%.

If it has a common BMS like almost every ebike pack out there, then yes, it does, in order to do it's balancing
...
But most common ebike batteries (not the OEM bigname bikes, but probably even some of those) are NOT made of good quality cells, and are NOT matched and tested, so they DO get out of balance easily, and the battery has to be fully charged in order to fix this.
…
Yes, a common ebike battery DOES have to be fully charged in order to operate the way it was designed and built.
…
all they really had to do was plug it in and let it sit on the charger for long enough to finish balancing (which by that point could take days or even weeks, but it will usually still fix it).

I'll try to remember to link to this to take those faulty suboptimal build & design factors into account. You've got a lot more patience than I do to lay out all the variables.

 

[amberwolf]

Not always.

But it can be very important sometimes to know the gotchas...and it's possible for someone to accept a blanket statement about something in a way that makes them think one thing, even though the blanket statement didn't have that intent. (like saying that jumping out of a plane is perfectly safe...which is true, under all the right conditions, with all the right equipment, and all the right training...but without all that, is a really risky thing to do. :lol: )

 

[furcifer]

I got one from Luna. It throws the 07 code at around 56.5V. They replaced it no problem. It was super annoying, forget to pull the battery off the charger and with a 21ah battery it takes a while to drain it down with a 100w light bulb. I think a hair dryer would work well but growing out my hair and getting it styled just to have an excuse to buy one seemed excessive.

I know Luna can flash the firmware. I was under the impression this was something only a dealer could do.

 

[amberwolf]

Anybody that has the cable and the firmware file, and the flashing software for a computer, can do it. The catch is getting all of those (teh cable is probably easy...the software and especially the firmware are likely to be specific to each model, possibly each variation of each model). There may even be passwords and passcodes (or some other secuity method, like a timeout date) required to open the files, in case they "accidentally" get distributed.

So a dealer is probably the only source for those things (since the manufacturer is unlikely to distribute them), and even if the dealer does not have an agreement with the manufacturer to not distribute them, it is in teh dealer's interest to keep the stuff to themselves, so they can charge for "upgrades" in firmware, or changes to settings that distinguish between different models (where there may be no actual hardware differences), or "special sauce" firmwares that have better setups than the standard ones, etc.

 

[furcifer]

Update: Tried my spare controller purchased on Amazon from Greenergia? It throws the 07 code as well, but at a higher voltage (57.5 maybe)

Bafang is OK but their engineering and quality control is stereotypically Chinese. I think if they weren't a Chinese company, a Chinese company would have cloned and improved the controller by now.

 

[amberwolf]

It's more likely that companies will (have, probably) clone the stuff but make it *cheaper*, rather than improving it. That's what usually happens.

 

[furcifer]

It's more likely that companies will (have, probably) clone the stuff but make it *cheaper*, rather than improving it. That's what usually happens.

I think that depends. I buy a lot of vape stuff from China and the cloners are very good. They seem to adapt and improve very quickly. But this is basically all CNC work. The electronics stuff is hit or miss.

Then there are other things you just couldn't imagine being made cheaper and somehow the Chinese find a way. Sometimes I'm not even mad, I'm impressed.

 

[GeoffS]

Hang on a moment...
This is the issue that earlier BBSHD have when pushing up to the 60V mark.
Go and find the 50A mod thread for the BBSHD (it's on here).....there is a mod called the "fool the display mod" that makes your display (that then reports to your controller) believe it has a few less volts.
I chose a 15S big pack that was slightly over the tipping point for giving an HVC issue. The solution on a 850C display was actually pretty simple!....snip the brown* (I think...go find...I'll look for you when I have a bit of time) wire going to the display and put a couple of diodes in series in there (you can use a resistor but diodes were favoured for some reason). They get a bit (tiny bit) of "forward voltage drop" (about 0.7V per diode), and this sneaks you under the cut-off.
Mine will pop a HVC error if I don't run that wire through the diodes. I engineered a tiny switch that bridges across the (I think I used 3 diodes) diodes so that when the voltage is down a bit I hit the switch to make my voltage (power remaining) a shade more accurate.
I'll see if I can find you the thread later.
Try searching "fool the display" though <--- I tried that...it didn't work as I may have been using the wrong search words but follow the link below...It worked a treat BTW

*I checked...it is the brown wire

 

[GeoffS]

OK....start reading about here:
https://endless-sphere.com/forums/viewtopic.php?f=3&t=83778&start=75

 

[tomjasz]

Another Bafang nightmare. Do others a favor and ask for the compiler and share the file here. Luna is keeping the fix a secret.

Next, pay the couple of extra bucks to support a dealer, not a China reseller.

 

[tomjasz]

I got one from Luna. It throws the 07 code at around 56.5V. They replaced it no problem. It was super annoying, forget to pull the battery off the charger and with a 21ah battery it takes a while to drain it down with a 100w light bulb. I think a hair dryer would work well but growing out my hair and getting it styled just to have an excuse to buy one seemed excessive.

I know Luna can flash the firmware. I was under the impression this was something only a dealer could do.

Anyone can flash with the correct bin files. And Luna got caught in it too. But won’t budge on helping anyone here.

 

[furcifer]

Another Bafang nightmare. Do others a favor and ask for the compiler and share the file here. Luna is keeping the fix a secret.

Next, pay the couple of extra bucks to support a dealer, not a China reseller.

Well one went back to Las Vegas the other day. Luna wanted theirs back but I still have it. I'll send it back when I get around to it...

I need an Excel sheet to keep track of the controllers. 1st fried after 1 week, 2nd low voltage, 3rd fried, 4th low voltage and the fifth one is operating normally. I'm swapping controllers every other week. I burned through the rubber gasket (which is glued to the motor side with cyanoacrylate?) and have become quite proficient at making them out of rubberized cork. So good I think I might have found a new side business.

 

[GeoffS]

tomjasz...
This bafang nightmare here should be easily sorted....my DOA M800 that I have (it's never run) is just about costing my sanity.
Cheers Bafang :/ (and carbon bike kits, for being congenitally useless)
Well...at least it's prompted me to learn something about CAN bus protocols (and fault testing) now

 

[BotoXbz]

There seems to be like three threads about this issue right now and no real answer on how to flash the new firmware:
https://endless-sphere.com/forums/viewtopic.php?f=28&t=100011&p=1464513#p1464513
https://endless-sphere.com/forums/viewtopic.php?f=3&t=83778&p=1464511#p1464511
https://www.reddit.com/r/ebikes/comments/bdg9au/bafang_bbshd_07h_error/

First the buggy throttle now this, f*** Bafangs garbage software, can't wait to put a VESC in there.

 

[kcuf]

someone consider offering

bbsxx controller rebuild service


gotta be many 02 03 cores

dead in the wild


bafang plays

controller games

 

[amberwolf]

Possible fix:
BBSHD Voltage Problem Firmware Update & Instructions