BMC v2, principles and operation?

[sgds23]

I have been trying to get a BMC v2t to work with a Roboteq HBL2350 controller with no success. I'd be interested in hearing from anyone who has had luck with that particular combination, but am even more interested in understanding the exact details of how the BMC v2t works so I have some chance of making sense of what I see.

'Frinstance... Everyone seems to agree that because the BMC motor is geared, you will not see any hall sensor transitions when manually rotating wheel forward. Less clear: should you see transitions when wheel is manually rotated backwards? And what triggers clutch engagement-- motor amps > 0?

What I see: I have not been able to get the hall sensors to trigger at all, even though I have triple checked my 5v supply voltage. But I have noticed that SOME phase wire orderings result in much more backwards turning resistance, even with throttle at 0. And with these orderings, when I advance the throttle, I will see motor amps (as reported by controller) increase, hear some weird clicks, and then the whole thing seems to shutdown with motor amps falling to zero and staying there no matter where the throttle goes.

Any hints on how to connect my empirical results with theory about the BMC v2t's operation would be much appreciated.

s.

 

[neptronix]

Hhmm..... why don't you just use an infineon controller like everyone else?

No theory needed, just plug it in and it works well

 

[sgds23]

Because I was able to replace 2 Infineon controllers + 2 Cycle Analysts + 1 Arduino with one Roboteq. It's a pretty sweet box,
http://www.roboteq.com/brushless-dc...-dc-motor-controller-with-encoder-hall-inputs.

 

[amberwolf]

Everyone seems to agree that because the BMC motor is geared, you will not see any hall sensor transitions when manually rotating wheel forward. Less clear: should you see transitions when wheel is manually rotated backwards?

Yes, only then (when rotor is not powered).

And what triggers clutch engagement-- motor amps > 0?

Clutches in these typically simply engage whenever the rotor turns part of it, forcing the bits against each other to cause friction agaisnt the rest of it, transferring rotor motion into the wheel. (via the gears).

So, it isn't just once amps is > 0, it is that plus when rotor speed is greater than wheel speed (vs ratio of gearing).

What I recommend is following hte same method used for all hub motors to determine operation:
http://www.endless-sphere.com/w/index.php/Determining_the_Wiring_for_a_Brushless_Motor
If you find a good backwards combo, the motor will spin normally but backwards, so thw heel won't spin.

 

[joec]

Sgds23- did you have an luck with this? I am presently looking at using similar motors with a Roboteq brushless controller, and I'm interested to know how it's working out. Hopefully you've had some luck! If not, then I'll be sure to post if I do anything to advance this.

 

[sgds23]

Yep, I got both the crystalyte and BMC to work with the Roboteq controller. Basically, all my problems stemmed from the controller's Microfit 3.0 connector, used for the 10 wires to/from Hall sensor info. Let me know if I can explain anything further, s.

 

[sgds23]

Actually, cancel that. I am having a problem with my BMC v2t in conjunction with the Roboteq controller.

It's an intermittent problem, usually occurs after running the BMC for anywhere from 30 seconds to 3 minutes. The motor will stop, the controller's "Short" indicator will come on, and the controller has to be restarted to clear.

I don't think my wiring is the problem--- it's not as if the wires are being jostled, or even vibrating. I'm thinking it's a phase wire problem inside the hub. Has anyone else had this problem with a BMC?

thanks,
s.