BBSHD over-current protection?

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endrew   100 mW

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BBSHD over-current protection?

Post by endrew » Apr 08 2018 3:23pm

Do the BBSHD controller has an over-current / over-heating cut-off protection? If I stress the motor too much (climbing a steep hill in a high gear for example) am I in risk of blowing the controller?

and a second question - when using the throttle, the bbshd always starts with a kick... is there a way to get a softer start?


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takis8vas   1 mW

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Re: BBSHD over-current protection?

Post by takis8vas » Apr 12 2018 1:59am

BBSHD controller maxes out at 30amps , it does have a temp sensor (as far as i know from the bbs02b controller i teared apart) that cuts the current when overheating to prevent any damage like controller damage or maybe nylon gear damage ;) You can make a programming cable and change the start current !

dustNbone   10 kW

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Re: BBSHD over-current protection?

Post by dustNbone » Apr 12 2018 8:25am

Running high current at low speed is hard on the controller, it's not a great idea but the BBSHD controller seems pretty robust, it's most likely to just get hot doing that. Use low gear to climb steep hills if you can.

As for the throttle, if you can program the throttle to "current" mode instead of "speed" mode in the programming software, I think it will behave much more like you want it to.

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fechter   100 GW

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Re: BBSHD over-current protection?

Post by fechter » Apr 12 2018 2:23pm

The kick problem you describe might be like the one i have. The problem happens when you are pedaling and try to apply the throttle it slams really hard. Pedaling only with no throttle works OK. Throttle only with no pedaling works OK, but if you do both at the same time it gets ugly. This was an issue with a certain vintage of controller firmware. There is no easy fix for the problem.

You can test by using the throttle only, being careful to NOT pedal and see if it runs smoothly.

If you have this problem, the only real solution is to replace the controller part. What I did was disable the PAS by cutting the grey wire so only the throttle works. I am happy with this solution. Alternately, you could disconnect the throttle.

Like any motor, if you really try, you can overheat it. I do a lot of climbing on really steep trails, so I replaced the chain ring with a 30 tooth and use low gear most of the time. I think the internal thermal protection kicks in around 60C. Even on a hot day, the most I've measured is 50C after a long climb. My other bike with a hub motor would overheat way earlier.
"One test is worth a thousand opinions"

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