Swapping controllers between different BBS02 models?

[bobbacon]

I'm trying to decide whether I should get a second 36v 500w bbs02 to be able to swap parts for troubleshooting, or, to finally get to try the 750w model. Had an idea though, as the title suggests. Is it possible to use a controller from a 36v 500w drive on a 48v 750w one, or vice versa, and then just use a battery with the proper voltage? Are the drives the same otherwise?

 

[bobbacon]

Got a reply from a reputable e-bike parts company, and they answered:

"It's not a good idea. The BBS02 motor structure is configured with windings that will provide the appropriately rated power at a particular speed when they are supplied with the correct voltage (36V or 48V). This means a 36V motor will be a faster wound motor to compensate for the lower voltage. BBS02 controllers are either 36V or 48V. They can only be used on their intended voltage.

The 36V version is designed to operate with 36V batteries (lower Low Voltage Cutoff and lower Over Volt Protection) whereas the 48V version is designed to work with 48V batteries (higher Low Voltage Cutoff and higher Over Volt Protection).

The 36V motor structure is specced for a 36V supply, if you were to swap the controller and run it at 48V, the motor speed would be rather fast, as motor speed is proportional to supply voltage. So really, you would need to swap the motor structure and also the controller. Do the opposite and the motor will run slowly."

In case anyone else have the same question.

Case closed!