What is the limitation of ultrasonic level transmitter

Ultrasonic level transmitters are widely used in various industries for measuring the level of liquids and solids in containers. These devices use sound waves to measure the distance between the transmitter and the liquid or solid surface. While ultrasonic level transmitters offer several advantages, such as non-contact measurement, high accuracy, and easy installation, they are not without limitations. In this article, we will discuss some of the limitations of ultrasonic transmitter.

1. Ambient noise: Ultrasonic level transmitters emit high-frequency sound waves to measure the distance to the liquid or solid surface. These sound waves can be affected by ambient noise, such as machinery or other sources of sound, which can interfere with the measurement and affect the accuracy of the transmitter. This can be particularly problematic in noisy environments, such as manufacturing plants.
2. Temperature variations: Ultrasonic level transmitters can be affected by temperature variations, which can cause changes in the speed of sound. This can lead to inaccuracies in the measurement of the level of the liquid or solid. For example, if the temperature of the liquid being measured changes, the speed of sound will also change, and this can cause errors in the measurement.
3. Signal attenuation: Ultrasonic level transmitters emit high-frequency sound waves, which can be attenuated or absorbed by certain materials, such as foam, vapors, or dust. This can cause errors in the measurement of the level of the liquid or solid. For example, if the liquid being measured is foamy or contains suspended solids, the ultrasonic waves may be absorbed or reflected, leading to inaccurate measurements.
4. Surface turbulence: If the surface of the liquid being measured is turbulent, such as in a tank where the liquid is being agitated or stirred, the ultrasonic waves may bounce off the surface at different angles, leading to inaccuracies in the measurement. This can be particularly problematic in applications where the liquid surface is not flat, such as in a reactor vessel.
5. Sensor positioning: The accuracy of ultrasonic level transmitters depends on the positioning of the sensor. If the sensor is not positioned correctly, the measurement may be inaccurate. For example, if the sensor is positioned too close to the wall of the container, the ultrasonic waves may bounce off the wall instead of the liquid surface, leading to inaccurate measurements.
6. Range limitations: Ultrasonic level transmitters have a limited range, which is typically between 0.5 and 50 meters. This means that they may not be suitable for applications where the liquid or solid level is very high or very low. For example, in a deep well, an ultrasonic level transmitter may not be able to measure the level accurately.
7. Sensor fouling: Ultrasonic level transmitters can be affected by sensor fouling, which can occur if the sensor is in contact with the liquid or solid being measured. Fouling can cause a build-up of deposits on the sensor surface, which can affect the accuracy of the measurement. For example, if the liquid being measured contains sediment or particles, these may accumulate on the sensor surface, leading to inaccurate measurements.

In conclusion, while ultrasonic level transmitters offer many advantages, they are not without limitations. The accuracy of the measurement can be affected by factors such as ambient noise, temperature variations, signal attenuation, surface turbulence, sensor positioning, range limitations, and sensor fouling. When selecting an ultrasonic level transmitter, it is important to consider these limitations and ensure that the device is suitable for the specific application.