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Ultra-compact cable extension sensor

The POSIWIRE sensor WS21 from ASM Sensors is designed for measuring ranges up to 20,000 mm. It is fitted with a robust, noncontact, magnetic multi-turn-sensing encoder, which gives wear-free operation and enables long measuring lengths to be packaged in compact designs. With a protection class of IP67/69K, this sensor withstands harsh environmental conditions and ensures high safety against breakdown in the field. Highly resistant to water, moisture, and condensation, the POSIWIRE WS21 sensors are designed to work reliably even in outdoor applications with large fluctuations in temperature. The high resistance against shock (100 g / 11 ms) and vibration (20 g, 10 Hz to 2 kHz) increases the functional reliability of the sensor, avoiding expensive machine downtime and repairs. A typical application includes linear measurements for crane booms. POSIWIRE cable extension sensors use a specially designed and calibrated measuring cable that is wound in a single layer onto a precision manufactured drum, which transforms the linear movement of the cable into a rotary movement. An angle sensor such as a potentiometer or a digital encoder finally converts it into an electrical output signal. For more information, visit

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