Level sensors are pressure sensors used to measure liquid levels, which can be categorized into two types based on the measurement method: contact and non-contact.
Level sensors are widely used in engineering applications, such as in the water treatment, metallurgy, and petrochemical industries, among others. Below, we will mainly introduce two different types of level sensors: contact and non-contact.
Contact Level Sensors: Capacitive, float ball, float, and pressure sensors all fall under the category of contact level sensors. During the process of liquid level measurement, they detect direct contact between the sensing element and the medium being measured. In some applications, a thick "scar" can quickly form on the sensing element, causing the sensor to malfunction.
When making a selection, it's essential to understand the performance of the medium being measured. Non-contact liquid level sensors come in two main types: radioactive isotope and ultrasonic. Radioactive isotope liquid level sensors are not suitable for large range measurements due to their limited range. On the other hand, ultrasonic liquid level sensors not only offer a wide range of measurement but also achieve non-contact measurement, unaffected by the medium's "scaling."
Disadvantages include the application of ultrasonic level sensors being constrained by factors such as medium temperature, ambient temperature, the degree of fluctuation of the measured liquid level, and various other external environmental factors. These constraints can severely impact the measurement accuracy of ultrasonic level sensors. Therefore, different level sensors are suited for different applications, and the choice between contact and non-contact sensors is based on the specific measurement requirements on-site. Then, the most suitable measurement principle for the current level measurement is determined.
