Bafang Reversed polarity

[jasethekiwiguy]

I just had my Bafang BBSHD arrive and screwed up big time and reversed the polarity. I didnt hear a bang, there was no smoke so when nothing worked I found the polarity issue. So the screen works fine with no errors but the engine does not run. How can I find out if I've blown the controller and if it isnt that what could it be? I have a multimeter but not great at using it. Id really appreciate any help, and yip I know Im a complete idiot! Too excited and moving too fast!

 

[Neeko DeVinchi]

If the bike turns on using the display (the display activates), then the controller (potentially to an extent) is functioning.
Does the display pop up any error codes?

Please take pics of the conversation so I can take a look ?

 

[Frankieboy]

Normally if you reverse the polarity on a DC motor it will go backwards, which isn’t a problem if connected to the battery directly. Have you tried to ride it with the wrong polarity? If so, it may have pulled too much current, as you would be peddling in the opposite direction to the motor, in which case it may have blown a fuse. Do you know if there is a fuse in the circuit anywhere?

 

[jasethekiwiguy]

I literally plugged it in and tried the throttle and nothing, then realised I had the battery around the wrong way. So i'm not even sure that my mistake caused the issue. The problem is I don't even know where to start with trouble shooting. I have no brake or gear sensors plugged in so it should just go. Is there a test I can do to find the problem Mate? (i keep hoping to find an on/off button Ive forgotten to push, ha)

 

[jasethekiwiguy]

There are no errors. But I noticed the battery is showing only 41Volts, also top right has what looks like a red battery (though it is 100% charged). Weirdly when I plugged it in just now the throttle gave a tiny little kick to the engine, first time that has happened, but I couldn't get to to happen again! If these photos aren't good enough, please let me know what you need Mate and I will take more. (thank you for your help!)

 

[Neeko DeVinchi]

Is that Silverfish battery pack 36v or, 48v?
Do you have the bafang programming cable?
Where are you based? I have colleagues who have an extensive knowledge of the BBS01, BBS02 and BBSHD so I might be able to see if they can reach out to you to troubleshoot.
TBT, I'm very knowledgeable regarding the Bafang M series motors (stripped and rebuilt more than I can remember) but fundamental similarities remain indicative throughout all bafang motors.
Please kindly get back to me ?

 

[jasethekiwiguy]

In in Stavanger, Norway. I ordered a programming cable a week ago, should turn up soon. I just read that if your battery is below a certain voltage you need to connect a programming cable and reconfig the controller for a lower voltage. My battery is a 48v 13AH, it was the cheapest i could find on ebay. Ive used it for 3 years with my 500w hub and it was perfect. Im starting to think its my battery and I didn't wreak it with my stupid polarity mistake. Is it possible that a Bafang just wont work at 41 volts? Dude, I would love it if you or your mates can help me! You're a legend for helping me.

 

[Frankieboy]

I literally plugged it in and tried the throttle and nothing, then realised I had the battery around the wrong way. So i'm not even sure that my mistake caused the issue. The problem is I don't even know where to start with trouble shooting. I have no brake or gear sensors plugged in so it should just go. Is there a test I can do to find the problem Mate? (i keep hoping to find an on/off button Ive forgotten to push, ha)

Sorry bud, I literally know nothing about Bafang, just a basic knowledge of DC motors / electrical circuits. looks like @Neeko DeVinchi and his pals are the people you need. Good luck!

 

[Neeko DeVinchi]

I've just sent a message to the only European specialist / colleague I know.
I'm still awaiting for a reply but his email address is, [email protected]

His name is Daniel and he's based it Italy.

He is also the European distributor for bafang products.

If he responds and gives me permission to share his personal number, I'll PM you privately @jasethekiwiguy

I'll keep you posted ?

 

[jasethekiwiguy]

You're a legend Mate! Thank you!