Rika RKL-03: How Ultrasonic Water Level Sensing Works

Rika RKL-03 is a non-contact ultrasonic water level sensor for liquid level and bulk material monitoring. On Fortuna Argatech’s official website, the product is shown with 0.5% to 1% accuracy, +/-3 mm or 0.1%FS resolution, 4-20mA/RS485 output, and support for Parshall Flume and V-Notch.

At a general level, ultrasonic level measurement uses sound pulses and echo timing to calculate distance and level. The method is non-contact, continuous, and suitable for liquids and bulk solids. (Endress+Hauser, Ultrasonic level measurement, n.d., https://www.endress.com/en/field-instruments-overview/level-measurement/Ultrasonic-level-measurement)

What is Rika RKL-03?

Rika RKL-03 is an ultrasonic sensor that reads the distance to the surface and converts it into level data.

Because it does not touch the medium, the sensor is a practical fit for sites that need stable readings, low maintenance, and easier field installation.

How Rika RKL-03 works

The sensor sends sound pulses

The sensor emits ultrasonic pulses toward the water or material surface.

The echo is measured as distance

The reflected signal is received by the sensor, and the travel time is used to calculate distance.

Distance is converted into level

The measurement is then turned into water level or material level data.

Data is sent to the monitoring system

The output can be sent to PLC, SCADA, or a monitoring dashboard for analysis and recording.

Key specs published by Argatech

Argatech’s product page lists measuring ranges of 5 m, 10 m, 15 m, 20 m, and 30 m, 4-20mA (2/4 wire) or RS485 (4 wire) output, 24 VDC or 220 VAC power, 0.5% to 1% accuracy, and a 1-year warranty. (Fortuna Argatech, Sensor Level Air Ultrasonik Rika RKL-03, March 2, 2026, https://argatech.com/sensor/sensor-level-air-ultrasonik-rika-rkl-03/)

Main details:

• measuring range: 5 m, 10 m, 15 m, 20 m, 30 m
• output: 4-20mA (2/4 wire), RS485 (4 wire)
• power: 24 VDC, 220 VAC
• accuracy: 0.5% – 1%
• resolution: +/-3 mm or 0.1%FS, whichever is greater
• probe protection: IP68
• display protection: IP66
• house material: anti-aging corrosion-resistant engineering plastics
• warranty: 1 year

When should you choose it?

This sensor is a good fit when you need stable, non-contact water level readings.

Typical use cases:

• rivers and reservoirs
• storage tanks
• irrigation systems
• wastewater treatment
• flood early warning systems

Can it be used for flow measurement?

Yes. Argatech says Rika RKL-03 can also function as a flow sensor in Parshall Flume and V-Notch installations.

That means it can help read level data that supports flow measurement in structures designed for that purpose.

Main benefits

• non-contact measurement
• low-maintenance operation
• LCD for on-site menu setup
• automatic temperature compensation
• usable for level and flow in specific setups

Rika RKL-03 and other Argatech monitoring solutions

If you need a broader water monitoring system, Argatech also offers AWLR.

Conclusion

Rika RKL-03 is a practical ultrasonic sensor for real-time water monitoring. For rivers, tanks, and flow structures such as Parshall Flume or V-Notch, it provides data that is easy to read and integrate.

FAQ

Sources

• Fortuna Argatech. (March 2, 2026). Sensor Level Air Ultrasonik Rika RKL-03 – Fortuna Argatech. https://argatech.com/sensor/sensor-level-air-ultrasonik-rika-rkl-03/
• Endress+Hauser. (n.d.). Ultrasonic level measurement. https://www.endress.com/en/field-instruments-overview/level-measurement/Ultrasonic-level-measurement
• Fortuna Argatech. (no date). Automatic Water Level Recorder (AWLR) – Fortuna Argatech. https://argatech.com/produk/automatic-water-level-recorder-awlr/