Ah, I see. I was thinking that somehow the signal coming out wasn’t a PWM signal, which confused me. You aren’t sure if the potentiometer on the power supply can be replaced with a PWM signal to control the speed. I don’t know if I would trust the bangood seller to know what you’re talking about either. I would bet that the potentiometer on the PSU would be fine if the signal was replaced with a PWM, but there’s more to that, such as finding the correct voltage.
Is the PWM controller going to survive limiting the power by that much? It looks kind of small. Do you know if it can handle 100V input when the PSU is in the high part of its duty cycle?
I’m going to guess this won’t work though, because if you set the PSU potentiometer to be 40%, the output is going to be a PWM signal, skipping between 100V and 0V, with 100V 40% of the time. The PWM controller will be doing the same thing, you’ll set it to 50% to get 50% power, and it will pass through the voltage 50% of the time, and clamp it to ground the other 50% of the time. The output would be 100V if both were on, and 0V if either were off. If the frequencies weren’t dramatically different, they would either completely overlap or completely miss, and probably switch between the two, so you’d get beat frequencies switching between off and 40V. Maybe I’m being pessimistic, and there’s some RC filtering, which will make these waves no big deal…
I don’t see any way this will destroy itself though, assuming you’re right when you say that 100V won’t hurt the motor momentarily.
I think you should test it. Start with the PSU at a very low value (confirmed with a multimeter) and hook it up the PWM and see if that output seems reasonable and stable (and those keep their smoke inside). At this point, you are only endangering the parts that you’d want to replace if something went wrong.
Then I’d hook up the motor, again, staying close to the bottom range of power until I was satisfied, and convinced that I needed more power, then I’d raise it up a little. Also keep in mind that the output of the PSU with no load might be completely different than with a load, luckily, it will probably be smaller, not larger with the motor.
If you have access to an oscilliscope, it would be interesting to see the output after the PSU and after the PWM controller, both with and without the motor attached.
Once you get it working, you might also think about replacing the potentiometer on the PSU with a resistor to avoid accidentally tapping that knob, which will mess up your set points, and possibly trash your motor or PWM controller.
