Page 148 - Sensors and Control Systems in Manufacturing

Classification and Types of Sensors

FIGURE 2.103 Tank level sensor. 109

sensing in the chemical industry (Fig. 2.103), the microwave sensor is
mounted at the top of the tank and measures the distance from that
position to the surface of the contents. Since the electronic circuitries
can be isolated from the tank contents by a sealed window, it is intrin-
sically safe. It has the advantage of being a noncontact system, which
means there are no moving parts to break or be cleaned. This allows
the microwave sensor to be used on aggressive chemicals, liquids,
liquefied gases, highly viscous substances, and solids such as grain
and coal.

2.10.8 Microwave Technology Advancement
Advances in technology have opened up important new applications
for microwave sensors. The expected governmental permission to uti-
lize higher frequencies and the decreasing size of signal processing
circuitry will significantly reduce the cost of the sensors and will
enable them to detect even smaller targets at a higher resolution.
Microwave integrated circuit technology (MICT), presently developed
for the Military Microwave Integrated Circuit (MIMIC) program will
overflow into the industrial market, causing increases in performance
and in analysis capabilities. Consequently, the utilization of computer-
integrated manufacturing technology will be broadened.