[en] On-line measurements of paper grammage, of moisture content of ash using XRF techniques is save many time and optimize the use of additives. Process computer serves as a data logger and as the interface between machine and operator. Data from the sensor are sent from the detector in standard current 4-20 mA. The signal is converted into a digital value, and calculation is performed on the dedicated computer module. The data is then sent to the process computer in wireless serial communication by using bluetooth media. Test as successfully performed in Results of design successfully tested in indoors with a maximum distance of 8 meters without interruption and no data loss. (author)