Endress+Hauser was contacted by a client in the Italian confectionery industry, for a level measurement issue in a tank, 3.5 metres in height, with a two-stage stirrer containing molten chocolate used to coat snacks. Chocolate is kept at a temperature of 40°C to safeguard its liquid state. The tank is loaded from the top, and a mass flow meter measures the chocolate as it flows in. The choice was made of installing an FMR60 radar level meter on a 2” support which was adapted for the 1 ½” radar. The slightly inclined bottom prevents disturbances in the detection of the empty tank signal. An RIA46 display was installed at the bottom of the tank for local viewing, with a maximum and minimum threshold set for level control. When the tank was completely emptied for the first time, a map of disturbances with the stirrer in action was defined, to prevent possible false echoes during normal use. Using the “map overlay” function, the signal and disturbances were recorded for a continuous 10-second period, so as to eliminate completely the various signals generated by the stirrer in motion.
