Working Principle
All materials have a dielectric constant, and its conductivity is different from that of air. When the probe is in contact with the material, slight capacitance shift will result in change in the total impedance. Because the electric probe and the vessel wall constitutes a second pole plate of the capacitor, the insulator of probe and surrounding air become dielectric material. When air (its dielectric constant 1.0) is replaced by any other materials (dielectric constant> 1), capacitance effect is enhanced, thus changing the impedance of the application, namely change in capacitance causes change in impedance. After this effect is measured by circuit, it will be compared with reference established by sensitivity setting.
Correct settings of sensitivity will affect the correct change of sensor output. The special circuit design of probe will render measurement circuit neglect the material deposited on the probe, otherwise it will cause the failure of sensitivity. The circuit is to be added to same radio frequency of sensor probe for potential incentives. Since the current cannot flow at the same potential, the circuit cuts off the current flow from electric probe through bulk material to container wall. Then the material surrounding the electric probe will be measured, rather than the bulk material.
Applications
1. Monitoring the material level of flour or wheat.
2. Monitoring the material level of coal ash.
3. Monitoring the material level of cement silo.
4. Monitoring the level of lubricating oil.
5. Monitoring the level of sewage.
6. Monitoring the material level of silica sand and broken glass.
7. Monitoring the material level of sand.
8. Monitoring the level of dacron, spandex, acid or alkali.
9. Monitoring the level of bubbly water or other pressure container.
