XKCON-return sensor, using the photoelectric conversion principle, outputs three sets of square wave pulses A, B and Z phases; A and B pulses are 90° out of phase, thus the direction of rotation can be easily judged, while Z phase is one pulse per revolution, which is used for reference point positioning. It has the advantages of simple principle construction, long average mechanical life, strong anti-interference ability and high reliability, and is used for horizontal rotation angle measurement of the reclaimer.