A quarry crusher works at its optimum when it is "choke" fed, the weight of the stone pushing down into the crusher creates an even feed into the jaws or cone of the crusher. In this application a cone crusher is maintained between 90% and 70% of its maximum capacity by an Ultra 3 working with a dB series transducer. Because of the variable nature of the stone, the echo processing has to be very good to provide an accurate level and stop the crusher either "starving" or overflowing. Pulsar's patented DATEM echo processing software is built in to all Ultra and Blackbox instruments. Click on the picture on the right, or here, to see a short streaming video of the application.