The Model SoliTrak is an Electro-Mechanic Level Measuring Instrument for the Continous Measuring of Level in Hoppers, Silos or Tanks. This Top Mounted System is used for Monitoring the Level in Applications, such as Powders, Small Grain Bulk Materials or Coarse Grain Bulk Materials. A Bob Weight is Mounted at the End of a Measuring Rope or Tape, which is Wrapped on a Motor Driven Rope Roller. Upon Contact with the Bulk Material, the Bob Weight Returns and is Drawn Back to its Upper Stop Position.