Programming the Bafang Middrive BBS01+BBS02

[Ken Taylor]

I used 'machine pin sockets' since they have a really nice round hole in them and seem to perfectly snap onto the pins. Then I just soldered some wires to the back of them and 'tinned' the bare wire at the other end for a push-in fit to my all-in-one USB to TTL adapter.

You have made extension wires with a male and female end which you don't need. Remove the plastic covers on the end of your all-in-one USB to TTL adapter wires to expose the female socket on the end of each wire. Lever up the plastic lock tongue and the plastic cover slides off. The female sockets will fit neatly on the pins in the Bafang plug. They are far enough apart not to touch but if this is a concern put heat shrink on them.

Do you have four pins connected? The second last picture shows 4 and the last picture shows 3. I thought it should be only 3. The risk in this approach is that you have to have the battery disconnected when you plug in and get the pin connections correct every time you plug in to the BBS0X or you are courting disaster. At least I suspect it would be disastrous to connect battery voltage to any pin on the the all-in-one USB to TTL adapter but maybe it isn't.

Edit: Looking more I think it's 5 wires required, thanks for prompting me to look more closely.

 

[pjgold]

Stock setting (20A), mine is pulling 1150W.

I haven't changed the main amp limit, just the assist % current limit in each of the assists. So assist setting 9 is set at 70% from memory.

It appears then that the main amp limit may have little or no effect ? and using the level settings is a better option.

 

[Kepler]

That could well be the case.

 

[aniken]

Sorry to be the dumbazz of this thread but if anyone can tell me about the power off feature of the controller I may be able to figure out why my bike turns itself off when you stop moving? If you keep moving i.e. the display is showing kph readout its fine, if you stop it turns off. You have to press the power button turn it on again, select mode and off you go.
It was doing it loads last night because I was testing without the chain connected so the wheel magnet wasn't spinning. I think its that 3 minute thing, if it sees inactivity for 3 minutes it turns off except mine does it even though you are moving and using pas and throttle just fine! Bike works perfect except when you stop, the speedo is kinda slow so it climbs down like 10-6-4-0 then it turns off.
I just don't ever stop, but sometimes you have to, like if a small child is in the way or something!

 

[shanman3us]

You have made extension wires with a male and female end which you don't need. Remove the plastic covers on the end of your all-in-one USB to TTL adapter wires to expose the female socket on the end of each wire. Lever up the plastic lock tongue and the plastic cover slides off. The female sockets will fit neatly on the pins in the Bafang plug. They are far enough apart not to touch but if this is a concern put heat shrink on them.

Do you have four pins connected? The second last picture shows 4 and the last picture shows 3. I thought it should be only 3. The risk in this approach is that you have to have the battery disconnected when you plug in and get the pin connections correct every time you plug in to the BBS0X or you are courting disaster. At least I suspect it would be disastrous to connect battery voltage to any pin on the the all-in-one USB to TTL adapter but maybe it isn't.

Edit: Looking more I think it's 5 wires required, thanks for prompting me to look more closely.

Your absolutely correct. I could have removed the rectangular plastic shells surrounding the 3 pertinent wires on the USB to TTL adapter BUT that would have permanently altered the adapter which, with my OCD and all, goes against my grain. However it is the more direct approach and then you only need to make the single wire that jumpers the PL to P+ (red in my case).

Thanks for the observation

 

[Kepler]

Sorry to be the dumbazz of this thread but if anyone can tell me about the power off feature of the controller I may be able to figure out why my bike turns itself off when you stop moving? If you keep moving i.e. the display is showing kph readout its fine, if you stop it turns off. You have to press the power button turn it on again, select mode and off you go.
It was doing it loads last night because I was testing without the chain connected so the wheel magnet wasn't spinning. I think its that 3 minute thing, if it sees inactivity for 3 minutes it turns off except mine does it even though you are moving and using pas and throttle just fine! Bike works perfect except when you stop, the speedo is kinda slow so it climbs down like 10-6-4-0 then it turns off.
I just don't ever stop, but sometimes you have to, like if a small child is in the way or something!

Could be the programmable auto shut off feature kicking in early. Do you know what it is set too? You need to get into the the advanced menu to set it. (See Bafang 961 manual if you are not sure how to do this)

Link to manual. http://www.bike-emotion.org/downloads/manual-of-c961.pdf

 

[Ken Taylor]

Thanks for the observation

No worries. I responded because I was waiting for my own similar plug to cure. It is based on:-

The black stuff is Sugru - air drying modelling putty - I put it on the cables when they were connected to the plug and let it dry overnight.

but without extension wires.

Remove the plastic covers, put the female connectors on the desired pins and push Sugru down into the plug so it will mould to the socket. It works amazingly well and only takes a few minutes to do but the curing takes a while. I left it 2 days to be sure.

That plug fits perfectly, goes on only one way and is tough, not fragile at all. I'll use this technique again if I ever need an unknown plug.

Even so the bought one:-

http://www.elektrofahrrad-einfach.de/products/Einzelkomponenten/Zubehoer/ELFEi-Zubehoer/ELFEi-Displayverlaengerung-fuer-Mittelmotor.html

is probably less bother as it doesn't have to cure.

I was worried it would stick to the plastic inside the socket and sprayed some olive oil in to make sure it didn't. With the plastic on these plugs I don't think it is necessary as it didn't stick on the outside of another that I tested without oil. I got too much in there so that the oil mixed with the Sugru and I had to squeeze out and waste some contaminated Sugru. I had plenty extra though as one sachet could do 2, maybe 3 plugs and has to be used once it is opened.

..then you only need to make the single wire that jumpers the PL to P+ (red in my case).

Bother, I left that wire out so will have to make another plug.

 

[programmer001]

I have changed thumb throttle to twist throttle on my BBS02 750W.
Now the motor starts ubruptly after a little twist.
There are jerks under 10 km/h.
The motor started rather softly on thumb throttle before.
Have anybody changed the throttle and it's setting?
Will it help to make throttle soft?
Or better to buy another twist throttle?
If I get the cable and try to programming the throttle,
what should I do? I don't understand all parameters there.
Can someone recommend appropriate twist throttle for Bafang?

 

[shanman3us]

I was worried it would stick to the plastic inside the socket and sprayed some olive oil in to make sure it didn't. With the plastic on these plugs I don't think it is necessary as it didn't stick on the outside of another that I tested without oil. I got too much in there so that the oil mixed with the Sugru and I had to squeeze out and waste some contaminated Sugru. I had plenty extra though as one sachet could do 2, maybe 3 plugs and has to be used once it is opened.

Now that is a beautiful plug you made. Nice work!!!!! I hear you about the Sugru packet and that's why I would choose to make my Sugru myself. It seems pretty easy and then you can make a batch virtually the quantity of what you want and it's so cheap you don't have to worry if you make a little too much. Just a quick Google search of DIY Sugru, AKA Oogoo...

Regards, Shanman3us

 

[Ken Taylor]

I have changed thumb throttle to twist throttle on my BBS02 750W.
Now the motor starts ubruptly after a little twist.
There are jerking on speed under 10 km/h.
The motor started rather softly on thumb throttle before.
Does anybody changed the throttle and it's setting?
Will it help to make throttle soft?
Or better to buy another twist throttle?

The throttle outputs a voltage proportional to the movement. I'd power it up and put a voltmeter on the output and move through the range. Compare the old and new throttle to figure out how they are different. Then work out what to do next.

 

[Ken Taylor]

Now that is a beautiful plug you made. Nice work!!!!!

Thanks, a credit to amigafan. I felt it rivalled Blue Poles, certainly neater, and also a bit like Blue Poles, doesn't require much talent.

... it's so cheap you don't have to worry if you make a little too much. Just a quick Google search of DIY Sugru, AKA Oogoo...

When I saw A$17 delivered for three little bits I thought of that route too and I did read about DIY Sugru but it's not the same stuff, so I invested. The novelty value, for me at least, is high. You could do 6 to 9 plugs from a packet but you'd need more than one Bafang cable for a mould as you'd have to make 2-3 at a time.

Having seen how tough it is, I'm confident the DIY stuff is not the same. Sugru is similar to silicon sealant but much easier to shape, like putty, and the final product is tougher, more like moulded rubber.

I can't understand why there is only one manufacturer, surely there is a good margin in it.

 

[programmer001]

I have changed thumb throttle to twist throttle on my BBS02 750W....

I'd power it up and put a voltmeter on the output and move through the range. Compare the old and new throttle to figure out how they are different. Then work out what to do next.

Suppose I use the voltmeter, but what to do next? I guess only programming or getting another throttle...

 

[Ken Taylor]

I have changed thumb throttle to twist throttle on my BBS02 750W....

I'd power it up and put a voltmeter on the output and move through the range. Compare the old and new throttle to figure out how they are different. Then work out what to do next.

Suppose I use the voltmeter, but what to do next? I guess only programming or getting another throttle...

Yes, but less guessing.

 

[flyingcubic]

I have changed thumb throttle to twist throttle on my BBS02 750W.
Now the motor starts ubruptly after a little twist.
There are jerks under 10 km/h.
The motor started rather softly on thumb throttle before.
Have anybody changed the throttle and it's setting?
Will it help to make throttle soft?
Or better to buy another twist throttle?
If I get the cable and try to programming the throttle,
what should I do? I don't understand all parameters there.
Can someone recommend appropriate twist throttle for Bafang?

Try to change Start Current and Voltage range



@All
is any new Firmware availabile?

 

[shanman3us]

Just checking....

I have the 500W 48V Bafang BBS02 and was just really looking at my 'low voltage cutoff' as set in the programming of the controller. The pack is a 13S 4P made up of Samsung INR18650-29E 2900mAh batteries.

Currently the low voltage cutoff is set to 41 vdc. I always like to err on the side of caution and was wondering if it is absolutely safe to leave it at this value or raise it a bit higher? I know that cellman (who I bought the pack from) has a lot of knowledge on this subject however on a lot of sites I have also read to never let the voltage drop below 3.3 vdc. Using the simple math that I think is correct (take 41vdc and divide by 13 cells) I get a low voltage cutoff that takes the cells down to 3.15 vdc.

Am I doing the calculation wrong and not taking something important into account?

Thanks,

Shanman3us

 

[pjgold]

Stock setting (20A), mine is pulling 1150W.

I haven't changed the main amp limit, just the assist % current limit in each of the assists. So assist setting 9 is set at 70% from memory.

It appears then that the main amp limit may have little or no effect ? and using the level settings is a better option.

I couldn't leave it alone without knowing so I connected the meter again and tested a few different settings in the main amp limit setting. I seems like the setting is 5A less than actual amps on the meter. Which makes sense when these BBS02 750w units are supposed to be 25A, however the software is set to 20A by default.
I've set my software setting down to 13A which on the meter at 100% pulls 18A or 800W.

I don't know if this is the case with all the other models or just specific to the 750W unit.

 

[etischer]

For those looking for the correct programming cable, this might work. Looks like it is the Bafang 9 pin connector (male and female), you would have to trace out the pins on the 5 pin connector back to this 9 pin, seems like it should work though.

http://www.greenbikekit.com/9pin-waterproof-connector-cable.html

 

[amigafan2003]

For those looking for the correct programming cable, this might work. Looks like it is the Bafang 9 pin connector (male and female), you would have to trace out the pins on the 5 pin connector back to this 9 pin, seems like it should work though.

http://www.greenbikekit.com/9pin-waterproof-connector-cable.html

Nope - totally different.

 

[shanman3us]

Just checking....

I have the 500W 48V Bafang BBS02 and was just really looking at my 'low voltage cutoff' as set in the programming of the controller. The pack is a 13S 4P made up of Samsung INR18650-29E 2900mAh batteries.

Currently the low voltage cutoff is set to 41 vdc. I always like to err on the side of caution and was wondering if it is absolutely safe to leave it at this value or raise it a bit higher? I know that cellman (who I bought the pack from) has a lot of knowledge on this subject however on a lot of sites I have also read to never let the voltage drop below 3.3 vdc. Using the simple math that I think is correct (take 41vdc and divide by 13 cells) I get a low voltage cutoff that takes the cells down to 3.15 vdc.

Am I doing the calculation wrong and not taking something important into account?

Thanks,

Shanman3us

Bump.......

 

[Ken Taylor]

Am I doing the calculation wrong and not taking something important into account?

The Cellman pack has a BMS which already has a low voltage cut off (LVC). You don't want to use the motor LVC, so set the voltage low enough that it will never function and rely on the BMS which does it better with a LVC per cell rather than per pack.

 

[shanman3us]

Am I doing the calculation wrong and not taking something important into account?

The Cellman pack has a BMS which already has a low voltage cut off (LVC). You don't want to use the motor LVC, so set the voltage low enough that it will never function and rely on the BMS which does it better with a LVC per cell rather than per pack.

Ohhh... This is absolutely new news to me. I didn't know that. Looks like I need to do some more reading on BMS's.

Thanks Ken...

Shanman3us

 

[Kepler]

Am I doing the calculation wrong and not taking something important into account?

The Cellman pack has a BMS which already has a low voltage cut off (LVC). You don't want to use the motor LVC, so set the voltage low enough that it will never function and rely on the BMS which does it better with a LVC per cell rather than per pack.

Cant say i agree with that. Typically the BMS is a hard cutoff that requires a power cycle to re set it. I don't have experience with Cellman's BMS's directly but this is what I have encountered with other BMS's.

Quite often towards the end of the charge, you can hit the LVC under high load. If you use the LVC built into the controller as the first line of defense, the LVC will re set itself and allow you to continue riding in a conservative manor. My experience is that the BMS LVC is used as the last line of defense, not the first.

 

[Ken Taylor]

Am I doing the calculation wrong and not taking something important into account?

The Cellman pack has a BMS which already has a low voltage cut off (LVC). You don't want to use the motor LVC, so set the voltage low enough that it will never function and rely on the BMS which does it better with a LVC per cell rather than per pack.

Cant say i agree with that.

Good to get another perspective.

Typically the BMS is a hard cutoff that requires a power cycle to re set it. I don't have experience with Cellman's BMS's directly but this is what I have encountered with other BMS's.

Yes my experience also. Once the BMS cuts out the voltage needs to go up by some amount before it reconnects. This seems a good algorithm to me as it doesn't oscillate.

Quite often towards the end of the charge, you can hit the LVC under high load.

Yes that happens occasionally with me, but in that case I find the battery recovers enough voltage to reset the BMS. More often I'm watching the battery voltage and sipping ever more gently as it approaches cut off. This is probably the best way to treat the battery at that stage.

If you use the LVC built into the controller as the first line of defense, the LVC will re set itself and allow you to continue riding in a conservative manor.

As does the BMS I am used to, from Cellman, if I have been drawing a lot of power from a small pack. I also have the same battery (different voltage) as shanman3us but it is a different BMS to Cellman's usual model and I haven't ridden it to cut off yet so I'm not sure if it is the same. I find the zippy's sag quite a bit under a heavy load and can cause the BMS to cut off but the LiFePO4 pack barely sags with load. The rate at which voltage drops with an empty battery is very fast and I think I'd find a motor continuously cutting in and out annoying.

My experience is that the BMS LVC is used as the last line of defense, not the first.

For battery protection, one line of defense is enough. The BMS does it better because it makes sure no cell falls below safe voltage. It is possible to run a cell below safe voltage while another is still well above safe voltage when only monitoring them in series. If you set the controller LVC below the BMS cut off it does nothing. If you set it above, you are not using everything the battery has to offer.

What would be nice is for the controller or BMS to reduce current draw to maintain the voltage above the LVC, then the assist would gradually fade away, but I haven't seen that algorithm.

 

[ErikDK]

Does the battery meter become useful if you raise the LVC?

Can you use make a 36V unit accept higher voltage by reprogramming?

 

[shanman3us]

@Kepler, Ken Taylor

I appreciate both of your input on LVC. I guess my main concern is that I never accidentally take the batteries too low to do any damage to their ability to retain capacity when they get recharged OR worse yet never revive to anything usable if dropped too low.

So, in line with my original question, is having the LVC in the controller set to 41 vdc for a 13s 4p 11AH (roughly) Li-ion pak just fine OR is the general consensus to change it to something different? If so, what are folks changing it to? I don't have a watt meter or anything else attached to my BBS02 500W motor. I have been erring on the side of caution and recharging before I even get close to the 41vdc LVC. Maybe this is not good for the batteries either?

Thanks in advance.

Shanman3us