Sensirion Liquid Flow Sensors
High-precision measurement even at minimum flow rates
Innovative Liquid Flow Sensor Technology
Sensirion's liquid flow sensors set a new standard, enabling monitoring of liquid microflow behavior, operating status, and dosage status anywhere. Our unique CMOSens® technology enables non-contact, bidirectional measurement of liquid flow rates from hundreds of mL/min down to single-digit nL/min through the outer wall of the sensor channel. The advantages of our safe and reliable sensor solutions are widely utilized not only in process control and automation technology fields but also in applications for medical devices and diagnostic equipment.
For more information, please refer to: www.sensirion.com/liquidflow
Patented Technology
Our CMOSens® flow sensor technology is based on a thermal micro-sensor and is most effective in the flow rate range below 1 L/min. The key element is a digital CMOSens® microchip attached to the outer wall of the sensor channel, which accurately measures flow rate through the channel wall. Our liquid flow sensors are completely non-contact with the medium, with no moving parts or obstructions in the flow path. By providing the world's smallest and most accurate liquid flow sensors, Sensirion contributes to the creation of designs and applications across all industries. Furthermore, their high reliability and inertness of wetted parts (chemical resistance) make them ideal sensors for medical, life sciences, diagnostic equipment, semiconductor, factory automation, and energy management applications.
In addition to the sensor element, the CMOSens® chip integrates memory with linearization and temperature compensation data, a self-test algorithm, and all necessary digital signal processing circuits. Various digital outputs (I²C, RS485, USB) and analog outputs are available for sensor connection. For customizable options, please contact us at info-jp@sensirion.com.
Flow Measurement Principle
The flow measurement principle involves a fluid channel with a heater element, a temperature sensor, and a micro-sensor chip mounted on the outer wall. Fluid flows through the channel, and the chip measures temperature changes caused by the heater and flow. Digital output is provided from the chip. The sensor utilizes internal capillaries of different diameters to cover a flow range exceeding 8 orders of magnitude, from nL to 1 L/min.
- Ballpoint pen: Approx. 100 nL/min
- Mosquito bite: Approx. 10 µL/min
- Mosquito bite: Approx. 5 mL/min
- Espresso machine: Approx. 500 mL/min
Our sensors can measure flow rates from nL/min to L/min. Please contact Sensirion if higher flow rates are required.
Product Series Overview
| Model | Full-scale flow rate (H₂O) | Full-scale flow rate (HC) | Measurement Accuracy (H₂O) | Bidirectional Measurement | Output Options | Max Cable Length | Fluid Connector Port | Max Pressure |
|---|---|---|---|---|---|---|---|---|
| SLF3S-0600F | 2000 µL/min | 2000 µL/min | 5% | O | I²C, RS485 | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 12 bar |
| SLF3S-1300F / SLF3C-1300F | 40 mL/min | 40 mL/min | 10% | O | I²C, RS485 | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/8" tube | 10 bar |
| SLF3S-4000B | 600 mL/min | 600 mL/min | 10% | O | I²C, RS485 | RS485: 100 m, I²C: 30 cm | Barbed fitting, Outer diameter 6mm tube | 3 bar |
| SLF3S-0600D | 2000 µL/min | 2000 µL/min | 5% | O | I²C, RS485 | RS485: 100 m, I²C: 30 cm | Down-mount | 10 bar |
| SLF3S-1300D | 40 mL/min | 40 mL/min | 10% | O | I²C, RS485 | RS485: 100 m, I²C: 30 cm | Down-mount | 10 bar |
| LD20-2600B | 1000 mL/h | - | 5% | O¹ | Analog (0-10V, 4-20mA), I²C, RS485 | RS485: 100 m, I²C: 30 cm | Barbed fitting | 3 bar |
| SLG-0075 | 5 µL/min | 80 µL/min | 10% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | Stainless steel 10-32 coned port, Outer diameter 1/16" tube | 1200 bar |
| SLI-0430 | 500 µL/min | - | 5% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 50 bar |
| SLI-1000 | 1000 µL/min | 10 mL/min | 5% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 12 bar |
| SLI-2000 | 5 mL/min | 80 mL/min | 10% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 12 bar |
| LG16-0150 | 80 µL/min | 70 µL/min | 5% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | UNF6-40 coned port, Outer diameter 1/32" tube | 200 bar |
| LG16-0430 | 500 µL/min | 500 µL/min | 5% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 100 bar |
| LG16-1000 | 1 mL/min | 10 mL/min | 5% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 15 bar |
| LG16-2000 | 5 mL/min | 80 mL/min | 10% | O | I²C, RS485, Analog (0-10V, 4-20mA) | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/16" or 1/8" tube | 15 bar |
| SLS-1500 | 40 mL/min | - | 5% | O | 0-10V, 4-20mA, RS485, I²C | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/8" tube | 12 bar |
| LS32-1500 | 40 mL/min | - | 5% | O¹ | 0-10V, 4-20mA, RS485, I²C | RS485: 100 m, I²C: 30 cm | 1/4"-28 Flat bottom, Outer diameter 1/8" tube | 12 bar |
| SLQ-QT105 | 120 mL/min | 120 mL/min | 10% | O | 0-10V, 4-20mA, RS485, I²C | RS485: 100 m, I²C: 30 cm | Super 300 type pillar fitting: 4x3mm, PFA tube | 12 bar |
| SLQ-QT500 | 120 mL/min | 120 mL/min | 5% | O | 0-10V, 4-20mA, RS485, I²C | RS485: 100 m, I²C: 30 cm | Outer diameter: 6.35mm (1/4"), Inner diameter: 4.35 mm | 12 bar |
Notes:
¹ SCC1 connectivity kit required.
² LD20 base station required.
Calibration: Water (H₂O), Hydrocarbons (HC).
SLF3x Series: Offers proven features with high cost performance. Unprecedented turndown ratio up to 1 L/min maximizes safety, stability, and long-term reliability in various mass-produced OEM applications. Fluid interfaces are available in tube and down-mount types.
LD20 Series: Enables liquid flow measurement up to 1,000 mL/h at the required location, realizing direct and effective patient treatment. It combines Sensirion's proven sensing technology with a disposable design suitable for mass production in fields such as biotechnology, life sciences, and the food industry.
SLG Series: For ultra-low flow rates down to single-digit nL/min, it is an optimal solution for dynamic liquid flow monitoring with high pressure and low flow, such as in cutting-edge UHPLC applications. The quartz glass flow path can withstand up to 1,200 bar.
SLI/SLS Series: Feature a protective housing packed with Sensirion's flow meter technology, making them ideal for experiments, research, and industrial automation. Combined with the SCC1 sensor cable (RS485/Analog/USB output), they enable reliable communication even in harsh environments.
LG16 Series: With inert wetted materials and performance for ultra-low flow rates, the LG16 series is widely used in demanding OEM applications. Its compact and simplified housing is suitable for integration into equipment and closed systems.
LS32-1500: Consists of a highly robust compact housing and uses chemically resistant wetted materials. It is a reliable solution suitable for many applications beyond the biomedical market, with flow rates up to 40 mL/min.
SLQ-QT105 / SLQ-QT500: With a calibrated flow range of 120 mL/min and the use of high-purity wetted materials (quartz glass, PFA), it is optimal for demanding coating processes in the semiconductor industry and for measuring liquids with high viscosity or containing particles.
SLD3P Series: A new generation of digital liquid flow sensors capable of measuring up to 5 mL/min. It combines accurate flow measurement, small size, and compatibility with multiple treatment methods, making it an ideal solution for mass-produced medical devices such as drug delivery patches and insulin pumps.
Evaluation Kit
To enable quick and easy initial measurements, all liquid flow sensors can be ordered as liquid flow evaluation kits. The evaluation kit includes the selected liquid flow sensor, plus cables, fluid/electrical connectors, mounting hardware, and everything else needed to start evaluation.
For more information, please refer to: www.sensirion.com/jp/lf-ek
Customization Solutions
Innovative ideas sometimes require new solutions. Sensirion's sensor experts conceptualize unique applications through our technology. For customization, we accommodate measurement flow ranges, space-saving requirements, resistance to corrosive chemicals, low cost, and also support the design of disposable sensors for mass production.
Sensirion's cutting-edge sensor technology and unique liquid flow sensing expertise have led to the success of various customer projects. Most importantly, it involves understanding customer needs and effectively leveraging our technology's advantages for customer benefit. Examples include modifications to packaging, wetted materials, fluid and electrical interfaces, dead volume, and improvements in sensor pressure resistance.
Key Features:
- Wide Flow Range: Years of experience and expertise combined with high-sensitivity sensors have enabled flow rate measurements from nL/min to L/min.
- Flexibility and Cost Efficiency: Sensirion flexibly meets customer needs with customized solutions that achieve high performance and cost-effectiveness through our cutting-edge technology.
- High Speed: The MEMS sensor integrated onto the CMOS chip enables ultra-fast response times of 20 ms through miniaturized calorimetric sensing.
