RTA ADW series stepper drives

The ADW series stepper drives from RTA have an analog speed control input instead of traditional step and direction signals. They are designed for variable speed applications rather than position control and are suitable for small conveyors and feed-rate control in machines.

In small machines, stepper motors are claimed to have several advantages over variable-speed AC or DC motors and drives. Their size is smaller for the same torque and, in some cases, gearboxes can be eliminated. The speed is constant and does not fluctuate with applied mechanical load or supply voltage. Speed can be controlled down to very low speeds, approaching zero revolutions per second. Synchronising of multiple motors is possible and stepper motors will automatically act as a brake at zero speed.

Motor speed can be controlled by an external potentiometer, external variable analog voltage or internal adjustment on the drive. Ramping of motor speed can be adjusted on the drive.

The ADW drives can run in four operation modes. In the Run mode, the motor start and stop are controlled by a single enable input. In the CW/CCW mode, the motor runs clockwise when one input is enabled and counterclockwise when another input is enabled. In the Start/Stop mode, the motor starts on the Start input signal and stops on the Stop signal input. In the Limit Switch mode, the motor will swing back and forward continuously, stopping and reversing when Fwd and Rev limit switches are hit.