replace pot on motor controller

[Craig]

I have a PWM motor controller that has a 10K pot to adjust the speed.
I have removed the pot and am wanting to use a 0-5 vdc analog signal
to change the speed. Hooked up the 0-5 vdc signal in place of the pot
and the control is backwards i.e. 0 = 100% and 5 = 0%.

What could I add to change this?

 

[hrh1818]

I have a PWM motor controller that has a 10K pot to adjust the speed.
I have removed the pot and am wanting to use a 0-5 vdc analog signal
to change the speed. Hooked up the 0-5 vdc signal in place of the pot
and the control is backwards i.e. 0 = 100% and 5 = 0%.

What could I add to change this?

Take your 0 to 5 volt signal and feed it into one input of an
inverting amplifier that has two inputs. Feed a -5 VDC signal into
the other input. Now when your input signal is 0 the output of the
inverting amplifier is +5 VDC. And when your input signal is +5 VDC
the output of your inverting amplifier is 0 VDC.

Howard

 

[Craig]

Take your 0 to 5 volt signal and feed it into one input of an
inverting amplifier that has two inputs. Feed a -5 VDC  signal into
the other input.  Now when your input signal is 0 the output of the
inverting amplifier is +5 VDC. And when your input signal is +5 VDC
the output of your inverting amplifier is 0 VDC.

Howard

Thank you