DIS Sensors’ QR series of rotary encoders enable contact-free measurement of an angular displacement from 0° to 360° without a mechanical stop. Two types of housing are available:
- QR30(N) – The sensor and magnet are mounted separately from each other
- QR40 – The magnet is integrated into the rotating shaft inside the housing
The QR30(N) housing in particular offers end-users a few benefits. It allows the customer to attach the provided magnet to the rotating axle (on-axis). Plus, the maximum distance of 3mm between the magnet and sensor accommodates mechanical tolerances under extreme conditions. The QR30 sensors offer various outputs with 10 or 12-bit resolution for diverse applications. The back of the QR30 sensors is sensitive, while the QR30N sensors have a sensitive nose.
In contrast, the QR40 housing has its magnet and sensor together. Standard shafts are D-shaped and the QR40 encoders have a zero-input allowing end-users to zero the device after installation.
Understanding Absolute vs. Incremental
The QR30 series is available as absolute or incremental rotary encoders:
- An absolute rotary encoder contains an analog output that is linear with the angle of rotation, up to 360°. After switching on the power, the sensor knows directly in which position it is located.
- An incremental encoder is suitable for the rotational velocity of a shaft. The output of the sensor consists of pulses (A and B). The number of pulses per revolution can be between 32 and 1024. On the basis of the phase shift between the A and B signal it can be determined if the shaft rotates clockwise or counterclockwise.