I have a DC Motor Speed Controller (PWM) that uses 100KΩ potentiometer to adjust motor speed. And I also have an electronic throttle pedal that used 49E Hall-Effect sensor (+5V, 0.8-4.2V signal, 1KΩ). I want to use this pedal with this speed controller.
I measured voltage drop on the potentiometer and it is 5V. Confirmed that pedal's signal changes from 0.8V (released) to 4.2V (fully pressed) when given 5V. What would be a right way to replace potentiometer in speed control unit with Hall-Effect sensor? Note, that I would prefer to preserve full speed control range (from 0% to 100%).
If you curious about my application - replacing binary on/off throttle in kids ride on car.
PWM controller built-in potentiometer works like that:
- Max speed: GND to wiper = 0V, wiper to V+ = 5v
- Min speed: GND to wiper = 5V, wiper to V+ = 0v
And Hall-Effect pedal is opposite:
- Max speed (fully pressed): GND to signal = 4.2V
- Min speed: GND to signal = 0.8V
So as drop-in replacement pedal will behave more as a break :)
On further examination, it appears that potentiometer's
GND (I mean, one of its legs that I referred above as GND) is connected directly to input
GND of PWM controller (where negative terminal from battery goes). So, from practical standpoint, it's probably safe to assume that I also have
Xv at my disposal (
Xv however is variable, since it's coming from unregulated battery). But I think this extra voltage source makes this question less general and less useful for other people...