Level gauges and level switches are both used to measure or monitor the position of liquids, but they differ significantly in functionality, accuracy, complexity, and output signal type, which is often the main cause of the discrepancies
Functional differences:
Level switches (such as float level switches) are mainly used to detect whether the liquid level has reached a preset point, and when the liquid level reaches that point, it will produce a simple on/off signal to trigger an alarm or control other equipment. Its functionality is relatively simple and straightforward.
Level gauges provide continuous or quasi-continuous level readings, can display and record the specific height of the liquid level in the vessel in real time, can not only monitor the level of the liquid, but also make accurate measurements, and may have the ability to transmit data remotely or integrate into the control system.
Accuracy requirements:
The accuracy of the level switch is relatively low, and it is only necessary to accurately determine whether the liquid level has reached the set threshold.
In order to meet the requirements of process or safety specifications, level gauges often require higher measurement accuracy, especially in the chemical, pharmaceutical, food and beverage industries, where the error range of level measurement is strictly limited.
Technical Complexity:
The structure of the level switch is generally simple, and the cost is relatively low.
There are many types of level gauges, including ultrasonic level gauges, radar level gauges, magnetostrictive level gauges, guided wave radar level gauges, etc., these high-end level gauges use more advanced technology, such as microwave, acoustic wave, electromagnetic induction and other principles, so the manufacturing cost is higher.
Additional Features:
High-end level gauges often have more additional functions, such as self-diagnosis, communication interfaces (e.g. HART protocol, Modbus, etc.), historical data storage and analysis, etc.
Applications:
Level switches are commonly used for basic level alarms and controls.
Level gauges are widely used in industrial production environments that require accurate metering, process control, and a high degree of automation.
To sum up, level gauges are usually more expensive than level switches due to their more advanced functional requirements, higher accuracy standards, more complex technical implementations, and more additional functions.