Indumart Level Measurement Techniques
This link takes you to a five-part series on various techniques for measuring level. Part 1 discusses basic principles behind the techniques for measuring liquids, solids and slurries: pressure, level-sight, radiation, sonic principles and electrical properties, as well as a variety of techniques and equipment and advice for choosing the most appropriate method for your application. Part 2 covers pressure instruments. Part 3 is on radar level measurement basics, and Part 4 discusses using ultrasonics to measure level. Part 5 discusses capacitance level measurement techniques. The direct link is at http://www.indumart.com/literature.html.