A level sensor allows you to detect the fill level of a medium in a container such as a process or storage tank, a silo or an open channel. This makes it possible to measure media such as liquids, bulk materials or even gas (in liquid state). Level switches in turn detect whether a predefined fill level has been reached and then output a switching signal.
Bürkert level sensors and switches allow industrial processes in various sectors to be monitored, controlled and automated just as precisely and safely as processes in supply and environmental technology. Which sensor is right for your application depends on the medium, the installation environment and the requirements with regard to measuring accuracy.
Continuous level measurement: In the case of continuous measurement, the fill level of a medium is constantly measured and monitored. This type of measurement is primarily used in industrial containers, such as process and storage tanks, silos or open channels.
Limit level detection: In the case of limit level detection, a predefined limit value is monitored. When the fill level reaches the limit value, a signal is transmitted and an action is performed (e.g. pump switched off, valve opened). This makes it possible, for example, to prevent tanks being overfilled, to initiate refilling processes or to protect pumps from running dry.
Our portfolio includes measuring devices for both variants. These include level sensors for a wide variety of applications that take into account specific media properties and are also suitable for special hygiene requirements. Furthermore, Bürkert sensors for level measurement are wear-free, have low susceptibility to interference and are characterised by extreme robustness. This reliability contributes to the safety of your processes and is an important part of your fluidics control loop. Additional elements such as valves and flowmeters can be added to create complete level control systems, allowing you to intelligently measure, control and regulate your fluids.
Continuous level measurement ensures not only smooth operations but also consistently high quality in many industrial processes. Level sensors enable continuous monitoring of the fill levels of active and auxiliary substances in chemical and pharmaceutical production, and of raw materials and ingredients in the food and beverage industry. If a level sensor works in a contactless manner, even the strictest hygiene regulations can be met.
Continuous level measurement provides water suppliers with real-time data that enables automated, optimal control of feed pumps. Level gauges also play an important role in flood protection and water supply by constantly measuring and documenting the water level. Bürkert level sensors for continuous measurement primarily use radar technology, and sometimes ultrasound technology.
How do radar measuring devices detect the fill level? The antenna of a level measurement sensor emits radar pulses that are reflected by the medium and received back by the antenna as an echo. The fill level can be calculated based on the time between sending and receiving the signal. Unlike an ultrasonic sensor, a radar sensor measures the fill level very accurately even under extreme process conditions. This is due to the high-frequency waves in the GHz range (higher frequency than ultrasound), which penetrate steam and dust and are not affected by pressure changes or mechanical influences such as rotating agitators.
+ Highly accurate measured values
+ Ideal for applications with aggressive media or dynamic process conditions, such as density fluctuations
+ Various connection types and sizes for a wide range of applications
Measuring devices with guided radar deliver more stable results than radar measurements without guidance and are therefore typically used in cases where interference could otherwise occur during the measurement process.
For example, foam formation can distort measurement results – in such cases, the probe is placed in a location with good measurement conditions. A level sensor with guided radar is also a good choice in larger containers or when it comes to measuring different layers of media in one tank. Please note: If there is an agitator in the container, the rod may cause interference; in this case, radar without guidance may be the better choice.
Ultrasonic level measurement is more susceptible to interference and may therefore deliver less accurate results depending on the process conditions. Temperature fluctuations, dust, fog or steam are some of the influences to which ultrasonic level sensors are sensitive. They are therefore less suitable for use in hot or dusty containers. Radar is also more reliable in terms of range, as the measuring accuracy of ultrasonic level measurement decreases at measurement distances above 10 metres.
Level sensors for limit level detection measure defined fill levels in process tanks, storage tanks, silos or pipelines. Minimum or maximum levels can be set, and the level sensors output a switching signal as soon as this fill level is reached.
Minimum limits are defined, for example, for syrup containers in beverage production. This ensures that production is stopped or a refill is initiated when a syrup container reaches the minimum fill level. Maximum levels are set, for example, in grain silos in agriculture to prevent overflow. When the silo is almost full, the level sensor detects the limit and reacts by stopping further feeding.
Level sensors that activate a switching function at limit levels operate – depending on the medium – using the tuning fork or float principle.
+ Tuning fork level switches are inexpensive and easy to install
+ Suitable for many application areas, such as those involving aggressive media
+ Reliable measurement even in the event of turbulence, air bubbles, foaming, adhesion, external vibrations and changing contents
+ Often also certified for potentially explosive atmospheres (ATEX)
Please note: The tuning fork must be able to vibrate – therefore, this type of level measurement only works in media with a suitable density range.
The tuning fork allows a level sensor to measure liquids, powders and bulk materials, making it suitable for level monitoring in a wide range of applications. These include, for example:
Bürkert offers vibration level switches with various suitability profiles for almost any application.
+ Cost-effective solution, easy to install
+ The density of the medium does not need to be taken into account – unlike with a tuning fork
+ Influences of pressure, temperature, conductivity or bubble/foam formation do not affect measurement results
Float switches are a good option whenever a simple and inexpensive solution for measuring the fill level of liquids is needed. They are therefore used in water supply and wastewater technology as well as in the food and beverage industry, energy technology and in the chemical and pharmaceutical sectors. Our portfolio includes float switches for both neutral and aggressive liquids.
Bürkert offers optimal solutions for a wide range of industrial and utility applications. Since we cover a wide range of different measurement principles, you are sure to find the right level sensor for your requirements. You can rely on the fact that the materials used meet the highest standards and can be integrated seamlessly into existing systems.
