Level Switches are used to send a signal when the level in a tank or vessel reaches a certain height. The medium sensed can be liquid, a slurry, or even solid. The traditional level switch is the float type, which is used in many applications. Other types in use are optical sensor switches, which uses an infrared sensor.
Level transmitter is used to measure the level of a liquid or bulk solid material within a specified space and to provide electrical output about these measurements that are proportional to the input level. This is used to measure level based on either a point level or continuous level readings. Point level transmitters provide output when a specific level measurement is reached. This is generally in the form of an audible alarm or an electrical charge to actuate a switch. This can be integrated together to give a stepped version of continuous level. They can operate through a wide range of temperatures, pressures, vapor gas mixtures, and process conditions. Some of the transmitters have air bubblers, which use a constant volumetric rate of gas flow fed through a bubble tube submerged in a liquid. Some use pressure membrane as a detector. These devices have a pressure sensitive switch with pressure transmitted to an internal sensor via an organic, or thin metal and membrane. Its ambient operating temp is +5°C bis 70°C. The sensor measures the pressure and the data is transmitted by a 4 to 20 mA output signal.
Level Transmitters are used to measure the level of a liquid or bulk solid material within a specified space and to provide electrical output about the measurements that are proportional to the input level. Level transmitters are designed to measure level based on either a point level or continuous level readings. Level transmitters use many different technologies to sense or measure level.