Designed for continuous liquid level measurement in tanks, wells, and open water bodies, submersible level sensors provide high accuracy and reliable performance, even in harsh environments.
Using sound waves to measure levels without direct contact, ultrasonic sensors are ideal for non-invasive measurement in applications involving liquids and solids across various industries.
Employing microwave radar technology, these sensors offer high-precision level measurement for liquids, powders, and bulk materials, ensuring reliable operation in extreme conditions.
A diverse range of specialized level sensors, including capacitive, magnetostrictive sensors, tailored for unique industrial and commercial applications.
Best 5 Level Sensor Types
Choosing the right level sensor for your water tank is essential for accurate liquid level monitoring. We’ve tested the most common level sensors on the market and identified the top 5 sensor types for water level measurement. Below, we compare their working principles, pros & cons, and best use cases to help you make an informed decision.
1. Submersible Level Sensors (Hydrostatic Sensors)
How They Work
Submersible level sensors measure liquid levels using hydrostatic pressure. A pressure-sensitive diaphragm or transducer is submerged in the liquid, and the pressure exerted by the liquid is converted into an electrical signal.
Applications
Water tanks, fuel tanks, chemical containers
Industrial processes: oil & gas, pharmaceuticals, chemical processing
Environmental monitoring: groundwater, rivers, lakes, flood monitoring
Marine vessels, offshore platforms
Pros
✅ High accuracy and precise measurements
✅ Large measuring range (up to 500m or more)
✅ Works with various liquids (water, oils, chemicals, fuels)
✅ Durable & resistant to harsh conditions
✅ Low maintenance & cost-effective
✅ Easy to install (directly submerged in liquid)
Cons
❌ Assumes a consistent liquid density (errors may occur if density changes significantly)
❌ Not suitable for solids or slurries
2. Ultrasonic Level Sensors
How They Work
These sensors emit ultrasonic sound waves, which travel through air or liquid, reflect off a surface, and return to the sensor. The time taken for the waves to return determines the liquid level.
Applications
Water tanks, reservoirs, pipelines
Bulk solid measurement (silos, hoppers, storage bins)
Distance measurement
Open channel flow measurement (rivers, streams)
Pros
✅ Non-contact technology (ideal for hazardous liquids)
✅ Wide range capability (liquids, solids, powders)
✅ High accuracy & reliable performance
✅ Easy installation & configuration
✅ Affordable & cost-effective
Cons
❌ Environmental factors (temperature, humidity, and obstructions) can affect accuracy
3. Capacitive Level Sensors
How They Work
Capacitive level sensors detect changes in capacitance between two electrodes when liquid levels change.
Applications
Water, wastewater, oil & gas, food & beverage, pharmaceuticals
Powders, granules, bulk solids in hoppers & silos
Interface detection (detects layers between different liquids/solids)
Pros
✅ Highly versatile (works with liquids, powders, and solids)
✅ Fast response time & high sensitivity
✅ Operates over a wide temperature range
✅ Easy installation & minimal maintenance
Cons
❌ Requires a significant dielectric difference between the substance and its surroundings
❌ Not ideal for transparent or non-reflective surfaces
4. Radar Level Sensors
How They Work
Radar sensors use the time-of-flight principle, emitting radar pulses that reflect off the liquid surface. The return time determines the liquid level.
Applications
Storage tanks (fuels, chemicals, water)
Water treatment plants, pumping stations
Food production & pharmaceuticals
Oil & gas industry
Environmental monitoring (rivers, flood detection)
Pros
✅ Non-contact measurement (ideal for hazardous or corrosive liquids)
✅ Highly accurate & reliable
✅ Works in extreme conditions (high pressure, temperature, dust)
✅ Low maintenance & long lifespan
Cons
❌ More expensive than other level sensors
5. Magnetostrictive Level Sensors
How They Work
These sensors use magnetostrictive technology, where a magnetic field interacts with a sensing wire to determine liquid levels with high precision.
Applications
Oil & gas, chemicals, pharmaceuticals
Water and wastewater management
Fuel monitoring in trucks
Pros
✅ High accuracy & stability
✅ Continuous real-time monitoring
✅ Compatible with various liquids
✅ Simple remote calibration using the Hart protocol
Cons
❌ Requires a large probe, which may limit installation in small spaces
Comparison Table
| Technology | Submersible | Capacitive | Radar | Ultrasonic | Magnetostrictive |
|---|---|---|---|---|---|
| Medium | Water, oils, chemicals | Water, oils, chemicals | Water, oils, chemicals (dielectric-dependent) | Water, oils, chemicals | Water, oils, chemicals |
| Accuracy | High | Medium | High | High | High |
| Range | Large | Medium | Medium | Medium | Medium |
| Compatibility | General | General | High | High | High |
| Price | Low | Medium | High | Medium | High |
| Installation | Submersible | Submersible | Non-contact & contact | Non-contact | Submersible |
Conclusion: Which Level Sensor is Best?
The best level sensor depends on your specific application, accuracy needs, and budget. Here’s a quick selection guide:
For cost-effective, general water tank monitoring → Submersible Level Sensors
For non-contact, affordable, and versatile measurement → Ultrasonic Level Sensors
For high precision and viscous liquids → Capacitive Level Sensors
For non-contact, extreme environments, and high accuracy → Radar Level Sensors
For highly stable and precise fuel/oil monitoring → Magnetostrictive Level Sensors
Regardless of your choice, all these sensors integrate easily with existing systems, controllers, and digital displays. Need help selecting the right sensor? Contact us today!
FAQS
What is a level sensor?
A level sensor is a device that detects and measures the level of liquids, solids, or granular materials within a container, tank, or silo. It helps monitor inventory levels, prevent overflow, and optimize industrial processes.
What does a level sensor do?
A level sensor monitors and transmits data about the height of a substance inside a tank or container. This data can be used for:
✔ Preventing overflows and dry running
✔ Controlling pumps and valves
✔ Automating industrial processes
Where are level sensors used?
Level sensors are used across various industries, such as:
✔ Oil & Gas: Tank level monitoring
✔ Water Treatment: Reservoir and wastewater management
✔ Food & Beverage: Liquid and grain storage
✔ Pharmaceutical & Chemical: Ensuring precise ingredient levels
Is a level sensor analog or digital?
Level sensors can be both analog and digital:
- Analog Sensors: Provide continuous signals (e.g., 4-20mA or 0-10V) to indicate fluid levels.
- Digital Sensors: Use binary or serial communication (e.g., Modbus, RS485) for precise monitoring.
What items use a level sensor?
Level sensors are found in:
✔ Industrial storage tanks
✔ Fuel tanks in vehicles and aircraft
✔ Boilers and water treatment systems
✔ Silo and hopper systems for solids
How do I choose a level sensor?
To select the right level sensor, consider:
✔ Material Type: Liquid or solid? Corrosive or non-corrosive?
✔ Measurement Method: Continuous or point level detection?
✔ Environmental Conditions: High temperature, pressure, or hazardous area?
✔ Accuracy Requirements: Contact vs. non-contact technology
How does a leveling tool work?
A leveling tool, like a bubble or laser level, ensures surfaces are even by detecting deviations from a horizontal or vertical plane. In industrial applications, electronic level sensors measure height or displacement accurately.
How to check a level sensor?
To test a level sensor:
✔ Inspect for physical damage or debris blocking the sensor.
✔ Use a multimeter to check electrical connections.
✔ Perform a manual calibration if readings are inaccurate.
✔ Check software settings for digital sensor configurations.
