# With sending one pulse into a motor, does that make it move a step?

1. Apr 19, 2014

### Aerozeppelin

Does changing the amplitude or width of these pulses do anything?

I'm trying to figure out how to increase a motors speed!

2. Apr 19, 2014

### Baluncore

A single short voltage pulse, applied to a DC motor, will cause it to advance slightly.

The area of the pulse is voltage * time which does not represent power, except in a resistor.
A motor is partly inductive so the current pulse will lag the voltage pulse. The power applied to the motor is the integral of (the instantaneous voltage multiplied by the instantaneous current).

Changing pulse amplitude or width will change the power delivered. But because of the inductive lag there will not be a simple relationship between amplitude, width and motor advance.

3. Apr 19, 2014

### nsaspook

If you mean a stepper motor and controller it's based on pulse speed and the number of pulses.
http://orientalmotor.com/products/stepper-motors/index.html

4. Apr 19, 2014

### Mordred

you didn't specify what type of motor, stepper, DC or AC. Stepper is a set of pulses with pulse patterns for the next step. DC is a similar process. AC motors speed can be increased with the use of a Variable speed drive. VFD, this type utilizes pulse width modulation which is a simulated AC current via digital pulses. Then amplitude and timing of the PWM signals can then be used to control the rotations of the AC motor.

edit: just noticed the title specifying step

check the specifications on your particular motor, however it will have similar patterns as per this article

http://hibp.ecse.rpi.edu/~connor/education/IEE/lectures/Lecture_8_Stepper_motors.pdf

Last edited: Apr 19, 2014