The CN0173 is a panel mounted speed control for step motor drives. The speed is set manually by the "Speed" potentiometer. The rate of acceleration and base speed are set by the respective trimpots.

Switching the "Start" input to ground causes the motor to begin accelerating from the "Base Speed" at a rate set by the "Acceleration" trimpot until the set speed is reached. The motor continues to run at this rate until the "Start" switch is opened. The motor then decelerates down to the base speed and then stops.

The CN0173 panel mounts through a ¼ inch hole and the "Speed" potentiometer takes a .125 inch shaft adjustment knob.