Bafang BBS01b help

[Tim Howes]

Hi all. Had a system failure earlier this year, thought due to failed controller. BBS01B 250w 36v. Symptoms were high pitched noise followed by intermittent power loss, followed swiftly by complete power loss. Had my LBS have a look who were confident it was the controller. Replaced like-for-like by me, straightforward. Worked for another hundred miles or so before experiencing the same thing again today. Was during a very wet ride, and although I made all the connections myself they are well waterproofed. I didn't use extra silicon when connecting the controller, however. Totally dead now. Any thoughts on what else could be causing this fault? Thanks

 

[guerney]

I didn't use extra silicon when connecting the controller, however.

Do you mean no extra silicone was used, just the gasket? The rubber gasket works well just on it's own, to keep water out, if the bolts holding the controller to the motor are sufficiently tightened - my bbs01b motor survived 13 seconds of complete submersion. The gasket is fiddly to secure properly, I used a bit of UHU glue to keep it in place, before bolting on the controller. If there isn't 5V between these two pins on the speed sensor cable, your new controller may be dead (red and black).

 

[Tim Howes]

Thanks, I'll test for a voltage at the speed sensor as you recommend. Yes I used the gasket and had no trouble getting it properly positioned

 

[guerney]

Check your battery voltage - if your battery isn't working, you won't see 5V on the speed sensor cable. Is your display working? Switch off the battery, disconnect the display, then switch on the battery before testing the controller's 5V. If your battery is working fine, and your controller is showing 5V, your display may be faulty? Water ingress possibly? If your display turns out to be faulty, test your old controller - if it works, you'll have a spare controller.

 

[jarob10]

Had a similar experience with bbs01 controllers dying. Switched to external KT controllers 4+ years ago which have been flawless, even on bbs02’s

 

[guerney]

Had a similar experience with bbs01 controllers dying. Switched to external KT controllers 4+ years ago which have been flawless, even on bbs02’s

That's very interesting - which KT controller did you use with your bbs01? Was all it easy to get working?

 

[jarob10]

Any KT controller should work, mostly I use the controller integrated into my hailong battery base.

You’ll need to splice into the hall / phase wires, but the colour codings have been established so not too difficult. Motor characteristics need programming into the KT controller too. Do a search on this forum for more details.

I think something as trivial as a blown hall sensor (ie water getting into the throttle) can blow the integrated bbs controller. KT controllers are way more robust - I run mine at max current all the time with no issues.

 

[Tim Howes]

Thanks for all comments. Battery voltage 37v. Charging to full before testing again. Display working normally. Sensor terminals reading 5v between black/red and black/white. Power briefly this morning on pressing throttle but no PAS and throttle stopped working now also. Any other ideas? This is exactly the same as what happened earlier this year when my LBS told me the controller was the likely culprit and a new controller did fix things briefly. Just puzzled as to how I've broken another controller so soon (if indeed that is the problem)

 

[guerney]

What cells does your battery contain? Maybe one of our battery experts will advise if it's due to a faulty battery or BMS?

Disconnect the throttle and leave it off, to simplify things, and let it all dry out somewhere warm for a few days and try again? That it happened during/after your very wet ride, could be coincidental. Of course, don't keep the battery anywhere near a radiator, and don't charge to full if you're not going to use it for a few days. I'd also disconnect the speed sensor, to dry that out just in case.

There was a thread recently where someone after a wet ride had issues: changed wiring harness, changed controller, and it turned out to be the display - I keep my display covered with a DIY rain hood made out of a thick clear plastic bag and gaffa tape. And every connector is covered with either self-amalgamating rubber tape plus 4:1 self-adhesive marine heat shrink, or just the former.

 

[jarob10]

Do you get an error code on the display?

 

[Tim Howes]

Guerney - I believe they are Panasonic cells. Battery has been rock solid since purchase in 2017.

The funny thing is, the previous failure happened in France in the warm and dry summer weather. So I wonder whether yesterday's wet conditions are a red herring.

I'll remove the throttle as you suggest and see what happens.

Feels like something very fundamental is wrong, given the two episodes in quick succession.

Jarob10 - no error code comes up on the display, all appears to be as usual.

Thanks again for all commentary

 

[guerney]

Symptoms were high pitched noise followed by intermittent power loss, followed swiftly by complete power loss.

The only time I have heard a high pitched noise from my bbs01b was with power loss at the motor over 2 years ago, when I had almost zero charge remaining and was attempting to go uphill. 'Twas completely fine after a full charge. There was no error code.

I believe they are Panasonic cells. Battery has been rock solid since purchase in 2017.

That's no spring chicken. I hope your next post isn't about how your ebike battery burned down your house.

 

[guerney]

Motor characteristics need programming into the KT controller too. Do a search on this forum for more details.

I fear this will lead to the arcane weird world of KT controller settings, which very few know what of - the payoff of course, being more robust, cheaper and more reliable controllers. I've only had one controller failure, and I murdered that myself (I think) trying to solder something on. The amazon kit seller sent me another free, because it was murdered within 12 months and he feared very public and extensive highly negative feedback, and I bought another from greenbikekit (thanks @peter.c ) because of a sudden bout of controller anxiety - once I've killed those two, and if they die within an unreasonably short space of time, my next victim may be a KT.

 

[Tim Howes]

Thanks for all comments. After several days drying out the system is still dead. Guerney - I have 5v between the cadence sensor pins as per your diagram - do you think this mean the controller isn't dead? I was going to contact the supplier to say it was, but am not sure how to diagnose. The previous fault was solved by a new controller, but only temporarily, so is it more likely that another part of the system is at fault? I appreciate the battery is old but voltage is good, and my LBS gave it a clean bill of health when I asked them to look at it regarding the first fault

 

[guerney]

Guerney - I have 5v between the cadence sensor pins as per your diagram - do you think this mean the controller isn't dead?

If you're getting 5V, your controller isn't completely dead... but testing controller components would be difficult to impossible, because of all the hard to remove silicone covering them. If you're certain that your battery or battery BMS is not causing the issue, you have no choice but to look at the display, controller, connecting cables, throttle and speed sensor.

I was going to contact the supplier to say it was, but am not sure how to diagnose. The previous fault was solved by a new controller, but only temporarily

If it were me, I'd send it back saying it's faulty - if faulty, they should give you a new one, or repair it under warranty.

 

[Tim Howes]

Thanks, I've contacted the seller and will see what transpires. Slightly tricky as they are in Germany... Gotta love Brexit.

I'm not sure how I would go about testing all the other components but I have a multimeter! Are there any good sources of guidance online without having to draw on the goodwill of those contributing to forum discussions...?

 

[guerney]

Thanks, I've contacted the seller and will see what transpires. Slightly tricky as they are in Germany... Gotta love Brexit.

I posted my controller to China, and the seller replaced it under threat of many negative Amazon reviews. Cost: about £20.

I'm not sure how I would go about testing all the other components but I have a multimeter! Are there any good sources of guidance online without having to draw on the goodwill of those contributing to forum discussions...?

I've seen many controller problems solved on this forum by knowledgeable members, but so far (2 years) nobody has delved through the silicone to test BBS controller components. It's easy to pinch the phase wires or damage the silicone connector covers when installing a new controller - perhaps cover them with a thin layer of insulating tape, just in case?

Sometimes threads about BBSXX(X) problems get no responses here. There's always Endless Sphere:

controller repair bbs01b site:endless-sphere.com - Google Search

..

 

[Tim Howes]

I installed the controller carefully but agree there are some rather vulnerable wires. Definitely closed without pinching and I don't think there was excessive flexion.

The main question in my mind is: could another component in my system be responsible for trashing the controller? I don't want to hassle the seller for a replacement, only to install it and find it gets fried again shortly thereafter.

 

[guerney]

The main question in my mind is: could another component in my system be responsible for trashing the controller?

What sort of connectors is your battery using? The reason why I ask is because a power spike killed my last controller, which was my own fault - I hadn't used wire strippers, used a craft knife... left two invisible nicks which arced and shorted, resulting in a very confused controller which swiftly died. The good news is, I've bought fantastic wire strippers since, learned to solder, and soldered the battery directly to the new controller which is still working wonderfully thounsands of kms later. Even when fitted by manufacturers, it seems bullet connectors can get hot and if they're badly manufactured, and just crimped, not soldered, perhaps they could cause Bafang controller issues? Here's a pic of one of my old bullet connectors after decapitation - note the melting silicone cover.

 

[guerney]

I don't want to hassle the seller for a replacement, only to install it and find it gets fried again shortly thereafter.

I would, you'd then know with a high degree of certainty that you haven't been unlucky with controllers. On the other hand, maybe your supplier has got a batch riddled with bad ones, and you'd be sent another one of those? I bought the one currently installed from greenbikekit.com (for about £80), who stupidly accept Paypal. The one which I got from the original seller under warranty, is a reassuring spare.