SEW encoder

An encoder is a device that encodes signals (such as a bit stream) or data into a signal format suitable for communication, transmission, and storage. Encoders convert angular or linear displacement into electrical signals; the former are implemented using rotary encoders with code disks, while the latter use linear encoders with scale rulers. Based on the readout method, encoders can be classified into two types: contact-type and non-contact-type.

The German SEW optical encoder is a SEW sensor that uses photoelectric conversion to transform the mechanical angular displacement of its output shaft into pulse or digital signals. A utility model for the German SEW encoder discloses an encoder wiring‑inspection device for AC servo motors, which is installed between the encoder and the controller of the AC servo motor.

┃ Common models of SEW encoders:

EV2C EV2R EV2S EV2T ES1C
ES2C ES1T ES2T ES1R ES2R
ES1S ES2S EG7C EG7S EG7R
ES7R EV7R ES7C EV7C ES7S
EX7S AS7Y

┃ The operating principle of the SEW optical encoder from Germany

The German SEW optical encoder is a type of SEW sensor that uses photoelectric conversion to transform the mechanical angular displacement of its output shaft into pulse or digital signals. It is currently the most widely used sensor. An optical encoder consists of an index disc and a photoelectric detection unit. The index disc features a series of equally spaced rectangular apertures cut around a circular plate of a specified diameter. Since the index disc is coaxial with the motor, as the motor rotates, the index disc spins at the same speed. A detection assembly comprising light-emitting diodes and other electronic components then outputs a sequence of pulse signals. By counting the number of pulses generated per second, the encoder can determine the current rotational speed of the motor. Furthermore, to identify the direction of rotation, the index disc can provide two pulse channels whose phases differ by 90°.

We offer customers a comprehensive range of high‑quality, competitively priced SEW products: the German SEW gearboxes, SEW motors, and SEW variable‑frequency drives, along with a full selection of compatible accessories and optional components, including SEW encoders, brakes, brake coils, brake pads, rectifier modules, braking resistors, communication modules, the SEW encoder card DER11B, the SEW bus card DFP21B, encoder communication cables, the SEW model converter UWS11A, and the SEW USB communication cable USB11A—covering the entire SEW product lineup.

Applications of Encoders

Automotive: The automotive industry uses encoders as mechanical motion sensors for speed control.

Consumer Electronics and Office Equipment: In the consumer electronics industry, encoders are widely used in office equipment such as PC scanners, printers, and document scanners.

Industry: In industry, encoders are used in labeling machines, packaging equipment, and CNC machines equipped with motor controllers. They are also employed for CNC machine control.

Medical: In the medical industry, encoders are used in medical scanners to control the motion of micro- or nano-scale devices, as well as automated equipment and dispensing pumps.

Military: The military also uses encoders in position-tracking antennas.