Programming the Bafang Middrive BBS01+BBS02

[darth_elevator]

....The BBS02 controller is not properly protected against over current from what I can tell....

Teslanv, thanks very much for posting that info from Paul. I didn't buy from Paul, but it's interesting hearing the take of someone who's sold so many of these kits.

So when the controller blows a mosfet, is it from excessive current or excessive heat? I was thinking it was from current, so I turned my current limit down to 22 and adjusted some other settings to try to avoid current surges. My friend put a temperature gauge on the outside casing of his controller. I guess whoever's controller blows first will tell us the answer?

 

[eMax]

I can understand Paul's point of view and if i purchased a drive off him, would not expect warranty on a failure if I had made unauthorised programming changes.

Cant say I agree with his point of view on the PAS settings though. Having a speed limit of any of the PAS settings makes no sense to me unless you are trying to comply with regional statutory requirements. Having a current limit on each PAS setting doe's however make perfect sense.

Perhaps there is an underlying problem with setting the PAS speed to 100% across the board however 4000Km of testing without issue plus setting up a dozen other bikes the same, again without issue suggests to me that perhaps we don't all need to panic quite yet. Reading between the lines, Paul is suggesting the controller has poor current control capabilities. That may well be the case and certainly there are settings within the drive that I believe could cause damage if adjusted incorrectly. Personally though, I don't think 100% on speed PAS across the board is one of them.

I agree with you. I can't see how having the same speed limit on each PAS mode can destroy units and cost thousands. He may have been talking about another setting (Start Current perhaps??), that I am not sure.

 

[izeman]

on the other hand i don't think there is ANYBODY here on the forum that has more experience and warranty issue's solved than paul. i don't see why he should give false information. there is no benefit for him doing so. he might be wrong in identifying the problem. i'm looking forward seeing where the discussion leads to.
i have a 13s hardcover pack from him made of the (not so powerful) 2900 cells. so i even reduced the power limit to 18a (instead of 20a) because i don't want complains from my 130kg+ customer going mountain biking with this setup.

 

[bgt]

I can imagine the stronger units are a bit more prone to mosfet failure. I use a 250W BBS-01 36V unit and have the current limit set to 10A. Speedlimit on PAS is 100% on all settings. The 10A is quite low so I don't expect a lot of problems. Start current is set at 30%.
Is the BBS-02 controller better?

 

[Tom L]

I got pretty much the exact same reply when I asked why my supposed 25A controller was only giving me 20A max. (Still not sure why that is btw).

Initially I thought it was a bit hypocritical considering he sells EB3 programming cables but perhaps those controllers are better protected / designed, so I'll cut him some slack on that one. And I certainly wouldn't expect warranty support if my tinkering caused a problem.

I will say that the start current on the controller I received from him did appear to be set a bit high (40%) but other than that the configuration was reasonable and would require no further tweaking for every day use.

The PAS speed limit setting is an interesting comment. Lets see what happens: the motor tries to spin the bike up to full speed (50km/h) using only the PAS power level available in the associated setting. How is this a problem if you are in the correct gear? The motor spins as fast as it can with the power available never reaching the speed limit. So what? It is not drawing excessive current due to the associated power limit. If it was a problem the controller or motor would run hot. They don't and I have never seen power control problems with my attached Wattmeter. The PAS levels follow the set power limits nicely. Cutting out assist at an arbitrary speed is not helpful.

Excessive start current is a problem - another respected dealer told me this caused many issues with the V1 controller.

This goes to the heart of the problem with today's configurable technology. Manufacturers have two choices:

1- An open system with good available documentation but limited warranty support if you choose to tinker.
2- A closed system to protect vendors from inappropriate use and warranty claims caused by poor understanding of the device. This unfortunately never works as has been proved time and time again (iPhone jailbreaking, Sony Aibo hacking etc...). People own what they buy and are free to do with it what they will.

There is a third choice - an approved dev kit and limited access to configuration (e.g. the Topfield digital TV set top boxes) though this usually ends up becoming a type 2 case as people push what they can do.

Open documentation and an agreement that unapproved configuration of the hardware voids the warranty (pop up warning or licence agreement in the software) is the way forward but few manufacturers can see this.

 

[cycborg]

Interesting. After I blew a controller (due to wiring, not settings), I ordered a new one from Paul. The thing I didn't like about my original controller (and the thing I was trying to change when I damaged it), was that the speed limits were too low at the PAS levels I wanted to run. For example, PAS 4 cut out at 32 kph, which is consistent with the numbers teslanv just posted. I asked Paul if he could program the new controller without speed limits, and this was his response (19 Aug):

The kits are now programmed with 100% speed for all PAS settings and current settings that start from 20% in assist 1 and increase in 10% steps up to 100% in assist level 9. You also have high steady state power available from the PAS as this value has been increased over the factory setting.

I haven't tried to download the new settings, but this is consistent with my riding experience with the new controller. But I guess these settings caused him some problems and he's gone back to older settings on the units he's shipping now.

FWIW I haven't encountered problems with the new controller over about 150 km at 500-600 W.

 

[astmacca]

But I guess these settings caused him some problems and he's gone back to older settings on the units he's shipping now.

If that's the case its very recent since he advised me PAS speed on all levels would be 100% when i ordered a couple of weeks ago.
Thats for a 48V/500W drive though, which is the 48V/750W limited to 18A.

 

[Rusty123]

I wonder if any of the tech wizards on this board would consider putting together a wiki to discuss the programming options. Pretty hard to suss out the useful bits from this long and twisted conversation.

 

[Aushiker]

Paul has now posted this on his website ...

The standard settings on the BBS02 are really not bad and in future we will only make small changes, to allow 100% throttle at all times, remove the 40km/h speed limit on throttle and for throttle to work in assist 0. We will not be making any other major changes and I would respectfully ask that users do not consider a failed BBS02 to be a warranty claim if they have made changes to the software.

Source: EM3EV

Andrew

 

[Tom L]

Fair enough.
I wonder if Cellman would be willing or able (NDAs and all that) to share what he knows regarding correct programming of the controller's parameters and the pitfalls he is aware of?
This could also reduce the possibility of him receiving warranty claims due to owner misconfiguration of the controller.

 

[Tom L]

I wonder if any of the tech wizards on this board would consider putting together a wiki to discuss the programming options. Pretty hard to suss out the useful bits from this long and twisted conversation.

I was thinking of putting together a PDF of what we know and how to do it but a wiki would be more suitable. Never done it before. Does anyone know the best free wiki hosting service? Something like https://meta.orain.org/wiki/Main_Page perhaps?

 

[Aushiker]

I wonder if any of the tech wizards on this board would consider putting together a wiki to discuss the programming options. Pretty hard to suss out the useful bits from this long and twisted conversation.

I was thinking of putting together a PDF of what we know and how to do it but a wiki would be more suitable. Never done it before. Does anyone know the best free wiki hosting service? Something like https://meta.orain.org/wiki/Main_Page perhaps?

http://endless-sphere.com/forums/viewforum.php?f=32

Andrew

 

[Tom L]

Ha! Right. I'll have a look at how it's done. Thanks.

EDIT: Hmmm. A quick look through the topics on that wiki showed it to have no vendor specific tutorials or a place to put them. Do you know if this is allowed there?

 

[astmacca]

Around page 10 of this thread people were talking about Surgu for making plugs. And also the DIY alternative Oggoo which is Acetic cure silicon sealer (Silastic here) mixed with Cornflour??

Bought some Selleys Glass Silicon Sealant from Bunnings today and mixed with some Whitewings brand cornflour. The real stuff not the wheat based fake stuff.

Made a small plug just to see if it worked and was very impressed. Whole thing (8mm diameter and about 12mm long) set in 10 minutes and 5 hours later you can only just smell acetic acid and seems fully cured. Very tough. That was a about 1:1 mix by volume. Am definitely going to try this for the programming cable plug.

 

[Tom L]

That acetic acid you can smell will corrode copper wire. Use neutral cure silicone.

 

[teslanv]

I was amazed at what my House's gas water heater did to my copper pipe from the Condensate drain...

After a couple years, the copper was just about GONE. I ended up replacing the copper drain line with PVC.

I would have never imagined...

 

[astmacca]

That acetic acid you can smell will corrode copper wire. Use neutral cure silicone.

Ah! Good point. Will try the Roof and Gutter stuff as that claims to be neutral cure and suitable for copper and other metals. Thanks.

 

[Rusty123]

I've also been corresponding with Paul regarding his programming settings. As I understand it, he is currently programming his controllers so that they deliver the same amperage at each PAS level, and only the motor RPM cutout is adjusted with the PAS (higher PAS = higher cutout RPM). This reminds me of a discussion in the "New Bafang Crank-Drive" thread several months ago about the merits of setting the throttle to maximum, and using the gears to adjust current. Opinions were varied, but it does make sense to me. I like the fact that one can maximize battery range by setting the PAS such that the motor cutout speed is below one's normal pedal cadence, but still preserve max torque for starting and low speed acceleration.

 

[Rusty123]

Ha! Right. I'll have a look at how it's done. Thanks.

EDIT: Hmmm. A quick look through the topics on that wiki showed it to have no vendor specific tutorials or a place to put them. Do you know if this is allowed there?

I don't know any thing about the Endless-Sphere eBike Wiki, but I did notice a few vendor specific articles, although many were stubs (no content). Tutorials are located about half way down this page.

http://www.endless-sphere.com/w/index.php/Main_Page#Electric_Bicycles

I can't imagine that a tutorial regarding programming the BBSOX would be prohibited.

 

[Rusty123]

The PAS speed limit setting is an interesting comment. Lets see what happens: the motor tries to spin the bike up to full speed (50km/h) using only the PAS power level available in the associated setting. How is this a problem if you are in the correct gear? The motor spins as fast as it can with the power available never reaching the speed limit. So what? It is not drawing excessive current due to the associated power limit. If it was a problem the controller or motor would run hot. They don't and I have never seen power control problems with my attached Wattmeter. The PAS levels follow the set power limits nicely. Cutting out assist at an arbitrary speed is not helpful.
.

I may not be understanding things correctly, but does the PAS setting cause power to cut out as a function of road speed (MPH or KPH), or as a function of crank speed (RPM)?

The latter makes sense to me (as a way to shift load from motor to rider), though not the former. And I thought the controller "speed limit" was a global setting, independent of PAS setting?

 

[hie2kolob]

Paul has now posted this on his website ...

The standard settings on the BBS02 are really not bad and in future we will only make small changes, to allow 100% throttle at all times, remove the 40km/h speed limit on throttle and for throttle to work in assist 0. We will not be making any other major changes and I would respectfully ask that users do not consider a failed BBS02 to be a warranty claim if they have made changes to the software.

Source: EM3EV

Andrew

Does anyone know how long Paul warranties the BBS02?

 

[Kepler]

The PAS speed limit setting is an interesting comment. Lets see what happens: the motor tries to spin the bike up to full speed (50km/h) using only the PAS power level available in the associated setting. How is this a problem if you are in the correct gear? The motor spins as fast as it can with the power available never reaching the speed limit. So what? It is not drawing excessive current due to the associated power limit. If it was a problem the controller or motor would run hot. They don't and I have never seen power control problems with my attached Wattmeter. The PAS levels follow the set power limits nicely. Cutting out assist at an arbitrary speed is not helpful.
.

I may not be understanding things correctly, but does the PAS setting cause power to cut out as a function of road speed (MPH or KPH), or as a function of crank speed (RPM)?

The latter makes sense to me (as a way to shift load from motor to rider), though not the former. And I thought the controller "speed limit" was a global setting, independent of PAS setting?

PAS cuts power as a function of road speed but dials down assist (limits current) as a function of crank speed. With the standard programming, the faster you pedal, the less assist you get. A feature I personally hate and have removed via programming. Lets hope my drive doesn't blow up now :lol:

 

[astmacca]

PAS cuts power as a function of road speed but dials down assist (limits current) as a function of crank speed. With the standard programming, the faster you pedal, the less assist you get. A feature I personally hate and have removed via programming. Lets hope my drive doesn't blow up now :lol:

I noticed that today on my first commute with the BBSO2 fitted. Not sure yet what i think of it but treated it as a signal to change up a gear.

What i find annoying is that the PAS cuts out at different speeds depending on level selected. I think i would much prefer if the only thing that varies with PAS level is the current / watts provided.

Anyhow, hopefully the adapter to make the cable will arrive tomorrow and i can see what the settings are stock.

 

[hie2kolob]

Just recently my second controller went belly up while riding along the Wasatch Mountain range. This controller with the original factory settings had not been reprogramed or modified in any way. I used only the first two preset PAS levels(out of the nine PAS level setting) PAS1 and PAS 2 (current 52% and 56% respectively) with no throttle in the ride. About one hour and twenty minutes and 18 miles into the ride the controller went out in PAS2. The motor enclosure was noticeably hot.

The controller was sent to Paul at EM3ev and he replaced it free of charge under warranty within a week or so. Here is part of the e-mail I sent him:

A couple quick questions: After having this happen twice, we would like to know how we can avoid it from happening again. There does not seem to be any protective fuse or breaker that would normally be found on an electric motor. With my experience as an electrician I have found that almost every motorized electric devise I have encountered has had some kind of protective circuity. Does the manufacturer plan on integrating something like this into their next model?

And Paul’s response:

The reason the latest unit failed was the settings we had used, it should hopefully be much better with the settings closer to standard. There is no protective device that is going to save the controller I’m afraid, it is not as simple as that. Hopefully the new settings will be safe and this problem does not occur again.

Unfortunately this reply did not boost my confidence in the product for after looking at the settings of the new replacement controller we found that there were no changes – everything was programed as the controller before.

Since the controller's malfunction seemed to be temperature related I installed a temperature sensor so that I could monitor how hot the motor was running while riding.

So that I do not hijack this thread by adding too much content the results can be found here:

http://endless-sphere.com/forums/viewtopic.php?f=28&t=62646&start=25

 

[Tom L]

Interesting. I did an 800m climb (400m to 1200m) that is documented way back in that thread somewhere. No trouble with the motor overheating at all. Maybe I'm geared lower than you.