Ultrasonic level transducers are widely used for level measurement in industrial tanks, cesspools, diesel containers, and other applications. They utilize ultrasonic technology to measure the liquid level in liquid or solid containers. This non-contact measurement method is used. These measurements are then converted into a standardized signal. This is used for monitoring, control, or displaying liquid level information.
Ultrasonic type level transmitters can meet most industrial level measurement needs at a low cost. They provide a high-precision, non-contact solution for industrial process control and monitoring.
What Is an Ultrasonic Level Transducer?
Ultrasonic level transducers are professional, non-contact, industrial level gauges. They utilize ultrasonic technology to measure liquid levels. They are primarily used for level detection of liquids, solids, and corrosive media.
Ultrasonic level transducers use non-contact measurement. They can measure liquid levels from 0 to 30 meters. They display the level in real time and can output signals such as 4-20mA and RS-485. They are suitable for industrial applications such as power generation, chemical processing, and food processing.
Working Principle
The working principle of an ultrasonic level meter is that the probe emits high-frequency sound waves. The liquid level is calculated by transmitting ultrasonic signals and receiving their reflections.
Once the liquid reflects the ultrasonic pulse signal inside the container, the sensor immediately receives the reflected signal. It then calculates the distance between the liquid surface and the sensor.
The propagation time of a sound wave is proportional to the distance it travels to the surface of an object. The speed of sound waves in a medium is c, and the time difference between the echo and the transmitted pulse is t. The distance S between the sensor and the surface of the object can be calculated using the formula S = C × T/2.
Types of Ultrasonic Level Transducers
Ultrasonic level transducers are used in various industrial fields. Sino-inst mainly provides the following types:
Four-Wire, Three-Wire, and Two-Wire Ultrasonic Level Transducers
Two-Wire Ultrasonic Level Transducers
Two-wire ultrasonic level transducers share a common power and signal circuit. They typically use a 4-20mA current loop for transmission. Power and signal transmission are accomplished via two wires.
Two-wire ultrasonic level transducers have a simple structure and low cost. They are suitable for explosion-proof and long-distance transmission scenarios. However, they are significantly affected by variations in line impedance.
Three-Wire Ultrasonic Level Transducers
A three-wire ultrasonic level meter is actually a four-wire system. Its power supply and signal output circuits are separate, each using two wires. When their negative terminals are connected to a common ground, three wires are usually sufficient. Its advantage is high transmission power. It is suitable for measuring liquid and material levels under various conditions.
Three-wire ultrasonic level meters are mostly powered by 24V DC. The output signal is either 4-20mA DC. The load resistance is 250Ω or 0-10mA DC. The load resistance is 0-1.5kΩ. However, the load resistance, or input resistance, varies depending on the output circuit configuration.
Four-Wire Ultrasonic Level Transducers
The power and signal of a four-wire ultrasonic level transducer are completely isolated, transmitted via two separate wires.
When powered by 220V AC or 24V DC, and the power supply circuit is completely isolated from the signal output circuit, a four-core cable should be used.
Four-wire ultrasonic level transducers offer strong anti-interference capabilities and high measurement accuracy. They are suitable for medium- and long-distance transmission or environments with high electromagnetic interference. However, wiring costs are relatively high.
Advantages of Ultrasonic Level Transducers
Advantages
- Non-contact measurement
Non-contact measurement reduces mechanical wear and maintenance costs.
- High adaptability
Ultrasonic level transducers are not affected by media characteristics. Such as DC values or density.
- High accuracy and stability
Employs intelligent echo processing algorithms and temperature compensation technology.
Some models offer an accuracy of ±0.25% to 1%.
- Wide operating temperature and corrosion resistance
Supports dual power supply: 24VDC/220VAC. IP65/IP68 rated. Suitable for use in high and low temperature environments, as well as corrosive environments.
Limitations
- A blind spot exists. Typically 30cm ~ 50cm.
- Susceptible to temperature and humidity.
- Susceptible to interference from bubbles and foam.
- Not suitable for gas measurement.
- Limited to volatile liquids.
Applications of Ultrasonic Level Transducers
- Chemical Industry
- Oil and Gas Industry
- Hydrology and Water Conservancy
- Food and Beverage Production
- Farmland Irrigation
- Pharmaceutical Industry
- Environmental Monitoring
Ultrasonic Level Transducer for Water Tank
Ultrasonic level transducers provide non-contact, continuous monitoring of tank liquid levels. They can be mounted on the top of the tank or externally attached to the bottom.
They are commonly used for water level monitoring in fire water tanks, sewage tanks, estuaries, and canals.
Ultrasonic Level Transducer for Diesel Tank
Explosion-proof ultrasonic level transducers can measure the liquid level in diesel tanks.
If the top of the diesel tank can be opened, the sensor can measure a range of 0-15 meters.
If the tank cannot be opened, the sensor can be mounted externally. We also offer oil ultrasonic level sensors specifically for small containers such as vehicle tanks and construction machinery fuel tanks.
Ultrasonic Level Transducer for Sealed Tank
Ultrasonic level transducers can also be used for level monitoring in sealed tanks. No openings are required in the tank. They feature an externally mounted design. They are suitable for corrosive and volatile liquids.
They are primarily used for level monitoring in sealed or inaccessible containers such as storage tanks, process tanks, and wastewater storage tanks.
Case Sharing: Explosion-Proof Ultrasonic Level Meter
Different Diesel Level Sensors for Diesel Tank Level Measurement
What Is the Difference Between an Ultrasonic Level Transducer and a Radar Level Transmitter?
Radar level transmitters and ultrasonic level transducers both use non-contact level measurement technology. The biggest difference between them lies in their different measurement principles.
| Main futures | Ultrasonic level transmitter | Radar level transmitter |
| Measurement Principle | Ultrasonic level transducers use sound waves. | Radar level gauges use electromagnetic waves. |
| Measurement blind zone | The probe temperature of ultrasonic level transducers generally does not exceed 80°C. | The blind zone of the radar level meter will be smaller. |
| Application Scenarios | Ultrasonic level transducers are suitable for use in atmospheric pressure and low-temperature environments. | Radar level transmitters can be used in high-temperature, high-pressure, or steam environments. |
| Temperature Range | The accuracy of ultrasonic level transducers is approximately 0.3% to 0.5%. | Radar level transmitters can measure high temperatures of 200°C and 400°C, and high pressures of 2.5 MPa. |
| Accuracy | The accuracy ofultrasonic level transducers is approximately 0.3% to 0.5%. | Radar level gauges have an accuracy of up to ±1 mm. |
| Cost | Ultrasonic level transducers are less expensive than radar level gauges. | Radar level gauges are more expensive. |
| Measurement Range | Ultrasonic level meters generally measure within a range of 0-30m. | The probe of the ultrasonic level transducer must be about 50 cm above the maximum liquid level. |
How to Use an Ultrasonic Level Transducer?
1. Ultrasonic Sensor Installation
The ultrasonic sensor is installed on a liquid or solid container. The probe must be aligned vertically with the measured liquid surface. Also, allow 50 cm of clearance during installation.
The installation location should be free from obstructions and vibration.
2. Power Connection
Connect the ultrasonic level transducer to a power source. Typically, ultrasonic level transducers use a DC power supply.
3. Signal Connection
Ultrasonic level transducers typically use a 4-20 mA current signal.
4. Parameter Adjustment
Set the operating parameters of the ultrasonic level transducer based on the characteristics of the medium.
5. Commissioning and Maintenance
We input the fixed distance (L) from the sensor to the bottom of the vessel.
The liquid level is calculated using the formula L – S.
Clean the probe surface regularly. Check for loose fasteners and ensure the signal is normal.
More Level Measurement Solutions
Ultrasonic level transducers are widely used for measuring liquid level and differential level. They are suitable for use in industries such as petroleum, chemical, and food. They can be connected to various DCS systems via 4-20mA or RS485 (Modbus protocol).
Sino-inst manufactures and offers a wide range of ultrasonic level transducers. These include top-mounted and bottom-mounted models, as well as corrosion-resistant and explosion-proof models. They offer optional two-wire and four-wire signal outputs, as well as control signal outputs. They are characterized by high accuracy, affordability, and durability.
If you need to purchase an ultrasonic level transducer or have any questions about it, please feel free to contact our engineers!