WORLD PULP&PAPER 85 the material (the paper sheet). The sensor’s active component converts the analogue measurement into high resolution digital data (corresponding to a resolution better than 0.1 g/m2) and is connected to a suitable digital data acquisition unit (the AMS_HUB). The measurement provided by the sensor is converted into a moisture value by the AMS_HUB where a special inversion curve has been implemented. This inversion curve was developed by the laboratories at A.M.E. to obtain extremely accurate values of the water contained in a material (g/ m2). Through the AMS_HUB, it is also possible to store and process the measured data, in real time, making it available on-line through remote connections as well as being able to transfer the data collected - transparently and in real time - directly to the DCS/QCS via standard analogue data lines (4/20 mA). The paper or pulp material being measured will then run between the sensor and the corresponding reflector (they are set 10-30 cm apart) without any direct contact. The data generated is managed by a dedicated CPU (integrated in the AMS_ HUB) which runs software that allows both the acquisition and the storage of the data, its display and its processing (FFT analysis), even independently of the DCS. The AMS_HUB also converts digital data to an analogue 4-20 mA format. The sensor provides its data continuously with a sampling frequency of 50 Hz (one reading approximately every 24 ms). The amount of data acquired is therefore relevant when considering the continuous operation of the sensor. It can highlight the effective dynamics of the process, given that the sampling frequency is sufficiently high when compared to the frequencies involved in this type of application – to the point of being able to identify typical periodic phenomena such as vibrations, pulsations and oscillations connected to the mechanics of the entire system through FFT analysis. Since paper manufacturing is a “periodic mechanical structure” (cylinders, felts, sheets but also pump engines, etc...), periodicity analysis, that is found “traced” onto the finished product, can be extremely useful when fully understanding the issues tied to the structural elements and how to best control them. AMS_R1 is, in short, the solution that transforms “tactile and visual sensations”, acquired over decades of experience, into something objective. This sensor provides the most complete, reliable, quantitative, very accurate, high resolution vision of the process, making the information available to an advanced, computerised process control system. APPLICATIONS The AMS_R1 sensor was developed to continuously measure residual moisture on the paper sheet during the manufacturing process in such a way that measurements are reliable, highly accurate and do not require contact with the said sheet. Measuring residual moisture allows the “dryness percentage” to be calculated (one of the fundamental parameters used to control production) at the points relevant for process control, such as leaving the press section, in various areas inside the drying section, Measuring residual moisture allows the “dryness percentage” to be calculated at the points relevant for process control Figure 3. Moisture measured at the forming board vs. moisture measured leaving the press vs. basis weight produced.