
Level Ultrasonic Sensor: Working Principle, Types & Industrial Applications
Level Ultrasonic Sensor Overview A level ultrasonic sensor is a non-contact device used to measure liquid or solid levels...
Home » Products » Level Measuring Instruments » Magnetic Float Level Gauge


The magnetic float level gauge is an essential instrument for industrial liquid level measurement. It operates by using a magnetic float that moves along the guide tube, transferring liquid level changes to an indicator or signal output device.
Ideal for chemical, oil, water, and corrosive liquid applications, it provides reliable and continuous monitoring of tank levels. The device is designed with robust materials, ensuring excellent durability even under high pressure or harsh environments.
With both direct visual readings and remote electrical outputs, this level gauge supports integration into modern automation systems, helping industries achieve efficient process control.
Level Measuring Instruments Description
Magnetic Float Level Gauge-Features
Simple and Reliable Design – Compact structure ensures stable operation, easy installation, and minimal maintenance requirements.
Separated Measuring and Connection Chambers – The working cavity and transmitter chamber are independent, enhancing safety and reliability.
Wide Application for Harsh Media – Suitable for thick, dirty, flammable, explosive, and corrosive liquids, ideal for demanding industrial environments.
Dual Display Options – Equipped with a field pointer and LCD screen for clear, real-time liquid level visualization.
Intelligent Signal Processing – Automatic zero and span calibration without manual switching, simplifying commissioning and adjustments.
High Measurement Accuracy – Precise liquid level detection; minimum adjustment angle can achieve 2°.
Advanced Output Capabilities – 4–20 mA current output with HART protocol support for seamless integration into industrial automation systems.


Applications of Magnetic Float Level Gauge
The Magnetic Float Level Gauge is widely used for continuous liquid level and interface measurement in various industrial processes. Based on buoyancy principles and a robust mechanical structure, it delivers stable and reliable performance even under harsh operating conditions.
Typical applications include:
Chemical Industry
Used for level and interface measurement of corrosive, toxic, and high-viscosity liquids in reactors, storage tanks, and process vessels. Suitable for aggressive media where reliability and safety are critical.
Oil & Gas and Petrochemical Industry
Ideal for monitoring crude oil, refined fuels, and chemical intermediates in storage tanks and separators. The all-metal construction and explosion-proof design ensure safe operation in hazardous areas.
Power Generation
Applied in boiler systems, condensate tanks, and auxiliary vessels for accurate liquid level indication under high-temperature and high-pressure conditions.
Water and Wastewater Treatment
Used for level measurement in clean water tanks, sewage treatment basins, and sludge systems. Performs reliably in dirty and particle-laden liquids with minimal maintenance.
Pharmaceutical and Food Processing
Suitable for hygienic applications requiring stable and repeatable level measurement. Optional stainless steel materials support clean and controlled process environments.
Shipbuilding and Marine Engineering
Applied in ballast tanks, fuel tanks, and service tanks where vibration resistance and long-term stability are required.
With support for local indication, 4–20 mA signal output, alarm switching, and HART communication, the float level gauge can be easily integrated into PLC, DCS, and industrial automation systems, making it a reliable solution for modern process control.
Magnetic Float Level Meter-Working Principle
The float (interface) level gauge is designed based on the principles of buoyancy and Hooke’s law. The float’s length corresponds to the measurement range.
When the float is suspended on the measuring spring inside the gauge and submerged in the liquid, it is subjected to the combined forces of spring tension, buoyancy, and gravity. The upward displacement of the float is proportional to the spring’s tension, and the change in spring length reflects the liquid level.
This displacement is transmitted to an external indicator via a magnetic coupling, providing a clear and accurate local liquid level reading.
The gauge features a full-metal construction, with the indicator fully isolated from the measured medium. It supports on-site visual display, as well as 4–20 mA two-wire output, switch signals, and HART protocol for integration with industrial automation systems.


Product Structure of Magnetic Float Level Meter
The Magnetic Float Level Meter adopts a modular all-metal structure with magnetic coupling, ensuring complete isolation between the measured medium and the indicator. According to display and safety requirements, the following configurations are available:
Basic Type
Without LED display, non-explosion-proof design. Suitable for non-hazardous areas requiring reliable local level indication.
LED Display Explosion-Proof Type
Integrated LED digital display in an explosion-proof housing, providing clear on-site indication for hazardous industrial environments.
LCD Display with HART Protocol (Explosion-Proof)
Equipped with an intelligent transmitter, LCD display, and 4–20 mA output with HART communication, enabling remote monitoring and system integration.
Structural Advantages:
Compact design, high reliability, corrosion-resistant construction, and flexible configuration to meet various industrial applications.
Level Measuring Instruments Parameter
| Parameter | Specification |
|---|---|
| Measuring Range | 300–6000 mm (customizable per user requirements) |
| Measurement Accuracy | ±1.5%, ±2.0% |
| Float Material | SS304, SS316L, HC, Ti, (customizable per user requirements) |
| Medium Density | ≥ 0.45 g/cm³ |
| Interface Measurement | Density difference between two media ≥ 0.1 g/cm³ |
| Medium Temperature | ≤ 80°C, ≤ 150°C, ≤ 250°C, ≤ 400°C |
| Medium Pressure | Standard: ≤ 4.0 MPa; High-pressure: ≤ 42 MPa |
| Pressure Rating | Standard: DN40–DN50 / PN4.0 MPa; DN80–DN100 / PN1.6 MPa High-pressure: DN40–DN50 / PN10.0 MPa Special: per customer request |
| Flange Standard | HG20592, DIN2501, ANSI, SH, GB (or per user request) |
| Process Connection | Flange DN50, G 1.5″ threaded, or per customer requirements |
| Output Signal | 4–20 mA DC (two-wire system) |
| Load Resistance | 500 Ω (powered by 24V DC) |
| Communication Protocol | HART, Modbus (RS485) |
| Alarm Output | Upper and lower limit switch isolated output |
| Contact Capacity | Max. 400 VAC 0.05 A, 24 VDC 0.2 A |
| Power Supply | 15–35 VDC, 220 VAC; Lithium battery 3.6 V 7.5 Ah, 220 VAC |
| Ambient Temperature | -20°C to +60°C |
| Housing Material | SS304, SS316L, or per customer request |
| Indicator Housing | Aluminum alloy, SS304, SS316L |
| Protection Level | IP65, IP67 (IP68 optional upon request) |
| Explosion-proof Rating | Intrinsically safe: Ex ia IIC T6 Ga, Isolated: Ex d IIC T6 Gb |
| Pressure Test | Tested 1.2–1.5× rated pressure per standards before delivery |
Instrava OEM/ODM
Instrava is focused on delivering reliable industrial solutions through carefully curated products, application-driven optimization, and flexible customization. We select proven instruments from trusted manufacturers to ensure consistent quality, optimize solutions based on real working conditions to solve practical challenges, and provide tailored configurations to meet specific application needs.
By combining selection expertise with application understanding, Instrava helps customers reduce risk, improve efficiency, and achieve dependable results in complex industrial environments.

Related Product Recommendations
What types of liquids can the Float Level Gauge measure?
The Float Level Gauge can measure water, oils, acids, alkalis, corrosive chemicals, and viscous fluids. It is suitable for a wide range of industrial applications, including chemical, petrochemical, and food processing environments.
How accurate is the Magnetic Float Level Meter?
Using precision float and guide rod design, this meter provides ±10 mm measurement accuracy. It ensures reliable and long-term stable performance for industrial liquid level measurement applications.
Can the Float Level Gauge connect to automated control systems?
Yes, models with 4–20 mA signal output can integrate with PLC and DCS systems for real-time monitoring, supporting automated control and data logging in industrial processes.
How often should the Float Level Gauge be inspected or maintained?
Routine maintenance includes checking the float and seals every 6–12 months. For aggressive or viscous media, more frequent inspections may be required to maintain measurement accuracy.
What installation considerations are necessary for optimal performance?
Install the gauge vertically and ensure the float moves freely. Avoid contact with tank walls or turbulence in the liquid to maintain accurate and stable level readings.
Is the Float Level Gauge suitable for corrosive or viscous liquids?
Yes, with appropriate material selection such as stainless steel or corrosion-resistant alloys, the gauge can reliably measure aggressive, corrosive, or viscous fluids in industrial tanks.
Built on Consistency, Not Claims
We specialize in industrial analysis and detection, with a clear understanding of real-world operating environments and requirements.
Every instrument is evaluated based on performance, stability, and application suitability—not just specifications or pricing.
We work with trusted manufacturers to ensure stable supply, consistent quality, and dependable delivery.
Our recommendations are grounded in application understanding, helping customers avoid common issues and achieve reliable results.
Instrava is built to reduce uncertainty—so every decision you make is clearer, safer, and more reliable.

Level Ultrasonic Sensor Overview A level ultrasonic sensor is a non-contact device used to measure liquid or solid levels...
Modern warfare has shifted from traditional battlefield confrontations to precision strikes targeting industrial infrastructure, energy systems, and supply chain nodes....
When a conflict ends, rebuilding begins—not just cities, but systems. Energy, water, chemical production, and infrastructure must be restored quickly,...