Level transmitters

Immersion pressure transducers are often used for level measurements. These pressure transducers are equipped with a special waterproof cable gland or a connector and are submerged right in the liquid. The high resistance of the cable and the shell of the transducer against corrosive effects of the medium ensure a long service life. As an example, we can mention a titanium version of the level transmitter tested in seawater applications mostly in the shipbuilding sector.

Measuring and recording important parameters such as level, temperature and conductivity can be decisive factors for important decisions in various industries.

Thanks to a series of high quality and smart meters for measuring these quantities, STS Sensor Technik Sirnach AG constitutes a trustworthy partner for all spheres of measurements connected with water whether with hydrology, sewage water treatment, water and potable water treatment or with geology, but anywhere the exact data from recording devices or by on-line transmission are indispensable part of your system.

Principle of hydrostatic pressure gauge for level measurement

The hydrostatic manometers are based on the hydrostatic pressure developed by a liquid column. The liquid column height h is its proportion. Pressure measurement is converted into measurement of length.

Hydrostatic method advantages

  • The sensors do not contain movable parts (such as floats).
  • The measurement is not affected by formation of vapour layers over the level or by foam on the level, the sludge at the bottom or the development of liquid layers of various densities do not matter.
  • The range of level measurement is substantially unlimited whereas the measurement within a wide range does not mean a higher price of the sensor.
  • the method can be used for measuring the levels of high viscous or contaminated liquids as well as for aggressive chemicals.
  • It is possible to measure liquids at high temperatures (up to 200 °C).

Division as per application method

Immersion probes

The immersion probes represent the simplest layout of the hydrostatic sensor. They are characterized by small dimensions and easy installation: they are usually suspended from the cable at the bottom of vessel and they measure the pressure of the ambient liquid. The interior of the probe is vented into atmosphere through a hollow core in the supply cable. Its lead into atmosphere is usually adapted in such a way so as not to be blocked by e.g. "malicious" activities of insects or not to be stuck up by condensed moisture.

Built-in sensors

The built-in hydrostatic probes and overpressure sensors with a diaphragm separator are usually installed in the wall of the vessel. The transducer body is located outside the vessel and it is vented into atmosphere. These sensors are also manufactured in a combined version with thermometers or possibly with a conductivity sensing element.