- #1
jfbrink
- 4
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Potentiometer as divider: How to use both "sides" of the split voltage?
Hello,
I am building a custom electric vehicle using an existing controller and motor combo.
The controller reads the voltage on two leads to control the speed of the motor and expects the voltages on the two leads to have an inverse relationship.
Thus, at zero throttle, lead A reads 5V and lead B reads 0V.
At half throttle, lead A reads 2.5V and lead B reads 2.5V.
At full throttle, lead A reads 0V and lead B reads 5V.
My question is: How can I achieve these results with a simple rotary potentiometer (and a few other components)?
Unfortunately, my electronics knowledge is more intuitive than actual, although I can read a circuit diagram. And my intuition suggested that putting a voltage input to the wiper and taking output from the two outer pins should work. And it seems to, briefly, but even at a very low current (an alkaline 9V battery), the RadioShack 5K potentiometers I'm using for testing start to smoke (!) pretty quickly.
Any hints, tips or outright answers?
Thanks,
Jesse.
Hello,
I am building a custom electric vehicle using an existing controller and motor combo.
The controller reads the voltage on two leads to control the speed of the motor and expects the voltages on the two leads to have an inverse relationship.
Thus, at zero throttle, lead A reads 5V and lead B reads 0V.
At half throttle, lead A reads 2.5V and lead B reads 2.5V.
At full throttle, lead A reads 0V and lead B reads 5V.
My question is: How can I achieve these results with a simple rotary potentiometer (and a few other components)?
Unfortunately, my electronics knowledge is more intuitive than actual, although I can read a circuit diagram. And my intuition suggested that putting a voltage input to the wiper and taking output from the two outer pins should work. And it seems to, briefly, but even at a very low current (an alkaline 9V battery), the RadioShack 5K potentiometers I'm using for testing start to smoke (!) pretty quickly.
Any hints, tips or outright answers?
Thanks,
Jesse.