Inst Tools - Instrumentation, Electrical, PLC Tutorials

Ultrasonic Level Switch Principle

Yet another style of electronic level switch uses ultrasonic sound waves to detect the presence of process material (either solid

A more primitive variation on the theme of a “tuning fork” level switch is the rotating paddle switch, used to

Tuning Fork Level Switch uses a metal tuning fork structure to detect the presence of a liquid or solid (powder

Some level switches use a float to sense the level of a liquid surface, actuating an electrical switch by the

Another electronic liquid level switch technology is capacitive: Sensing level by changes in electrical capacitance between the switch and the

A pressure switch is one detecting the presence of fluid pressure. Pressure switches often use diaphragms or bellows as the

A limit switch detects the physical motion of an object by direct contact with that object. An example of a

Perhaps the simplest (and oldest) form of electrical level detection is where a pair of metal electrodes contacts the process

An Optical Time-Domain Reflectometer or OTDR is a sophisticated test instrument used to probe the characteristics of long optical fibers.

Fiber optic cable testing is done to ensure all installed cable lengths and connectors are functioning properly.