Measurement Bridge for Large Grain Moisture Content Determination

Abstract

This paper describes the development of a moisture-measuring instrument suitable for large grains. The paper seeks to do the measurement based on the propagation of microwaves through materials of different moisture levels. The principle of operation here is sending an equally divided signal through both arms of the bridge and comparing the output signals’ properties to determine the moisture content of the grains. The design of the bridge using waveguide and coax technology is presented.

Ovaj rad opisuje razvoj pogodnog instrumenta za merenje sadržaja vlage u velikim količinama zrna (npr. skladišta, silosi). U radu se prikazuje merenje na osnovu prostiranja mikrotalasa kroz zrnaste ili slične materijale u masi različitih sadržaja vlage. Princip rada instrumenta je slanje podjednakih signala kroz oba kraka mernog mosta i upoređivanje osobina izlaznih signala radi određivanja sadržaja vlage u masi zrna. Predstavljen je dizajn mernog mosta sa korišćenjem prostiranja talasa kroz cevi i tehnologija koaksijalnih (optičkih) kablova .