A product sales
data processing system (1) includes: a sensor (10) attachable to a bulk food container (300) of a product; and a weighing apparatus (25). The sensor (10) includes: a sensor module (12) configured to detect a change of a tilt angle or a rotation angle of the sensor (10); a processor (11) configured to determine whether the tilt angle or the rotation angle is equal to or greater than a predetermined value; a memory (100) configured to store a sensor ID identifying the sensor (10); and a
transmitter (14) configured to transmit the sensor ID stored in the memory (100) when the processor (11) of the sensor (10) determines that the tilt angle or the rotation angle is equal to or greater than the predetermined displacement value. The weighing apparatus (25) includes: a
receiver configured to receive the sensor ID transmitted from the sensor (10); and a display (26) that is a touch display that receives a user operation, and is configured to display product information associated with the sensor ID, the product information including a product button that receives a user operation to specify the product as a weighing object.