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Level transmitter

Detect fill levels continuously at any time

Our level sensors enable the continuous detection of levels, independent of physical and chemical changes of the media such as foaming, conductivity, dielectric, pressure, vacuum, temperature, vapours, condensation, bubble formation, boiling effects and density change. Via the HART® interface, parallel measurement of interface layer and overall level is possible. The level can be displayed proportional to height or volume. Process connection, guide tube and float can be manufactured from stainless steel 1.4571, 1.4435, 1.4539, titanium or various plastics.

What are level transmitters and how do they work?

Level transmitters are sensors that are used to measure the level of liquids in vessels or tanks. They convert the measured fill level into an electrical signal (for example 4 ... 20 mA/HART) which can then be used for display or control of a process. These instruments are crucial for many industrial processes to ensure that the fill level is within safe and efficient limits. They can also be used for interface measurement.

How does a magnetostrictive level transmitter work?

A magnetostrictive level transmitter, for example, the model FLM-CA, uses a magnetic float along a waveguide. When an electrical impulse is sent through the waveguide, the interaction with the magnetic field of the float creates a torsional wave. The time between the impulse and the wave is measured to determine the level precisely. This technology is particularly useful in applications that require high precision and reliability.

How do reed chain level transmitters work?

A reed chain level transmitter consists of a large number of reed contacts connected in series and installed on a printed circuit board. When the liquid level changes, the float moves up and down along the reed chain. The magnetic system inside the float closes the respective reed contacts at the different liquid levels as it moves. The change in level thus causes an analogue change in the output signal. The rastering of the reed chain, in turn, defines the resolution and accuracy of the reed chain level transmitter.

For which application areas are magnetostrictive level transmitters or reed chain level transmitters suitable?

Magnetostrictive level transmitters offer very high accuracy and are ideal for demanding applications. They are particularly suitable for environments where precision and reliability are crucial. Magnetostrictive level transmitters are also particularly suitable for high or low temperature applications, as only very few components are exposed to the extremes of the process temperatures. Reed chain transmitters are easier to install and more cost-effective, making them ideal for standard applications. In addition, reed chain level transmitters are particularly suitable for harsh ambient temperatures with strong vibrations. The choice, therefore, depends on the specific requirements of your application, such as accuracy, cost and installation environment.

What are the advantages of float-based level transmitters?

Float-based level transmitters have the advantage that they can be commissioned very quickly, as all important settings are already made by the manufacturer during the production process. However, the greatest advantages of float-based level measurement lie on the process side. Float-based level transmitters work independently of foaming, temperature fluctuations or the permittivity of the medium.

In my application I have strong vibration. Which level transmitter should I use for my application?

For applications with strong vibrations, reed chain level transmitters should generally be used, such as, for example, the model FLR-S. Reed chain level transmitters are very robust against mechanical loading.

FAQ
FAQ

For which measuring instruments is a manufacturer's statement on regulation (EC) 1935/2004 required?

Within the EU, all articles and materials that come into contact with food (food contact materials, FCM) are subject to regulation (EC) No 1935/2004.

For food contact, the measuring instruments are typically fitted with hygienic, easy-to-clean conn ...

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How does a level sensor work?

These level sensors work on the float principle with magnetic transmission. The float's magnetic system actuates a resistance measuring chain that corresponds to a 3-wire potentiometer circuit in the guide tube.