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SFM4300-20-O

Pressure-resistant flow sensor, multi-gas, 20slm, O-ring fittings

The mass flow meter SFM4300 features improved sensitivity and precision, even for low flow rates. The small, compact sensor is calibrated for air, O₂, CO₂ and N₂O gases and – in contrast to its predecessor, the mass flow meter SFM4100 – it can also be used to monitor gas mixing. With a zero-point accuracy of 0.005 slm for a total range of up to 50 slm, the SFM4300 enables precise adjustment of the concentration in a wide selection of mixtures. The sensor unit has an I²C interface and produces a fully calibrated and temperature-compensated output signal. The mass flow sensor can be used for both medical and industrial gas mixing, fuel cells and for other OEM applications. In addition to inspiratory, expiratory and proximal flow measurement, Sensirion offers sensor solutions for gas mixing applications. These sensors are mainly used in anesthesia machines and are usually integrated into the overall machine. If we want to guarantee the patient’s safety while taking accurate, reproducible readings, we need the flow sensors in the machine to be stable and reliable – throughout the machine’s service life. Therefore, the Sensirion SFM4000 series is the ideal solution. It is is devided in two sensors: SFM4300 and SFM4200. The SFM4300 sensor can operate at pressures of up to 6 bar, store multiple gas calibrations and even perform self-testing while in use. Where safety and reliability are concerned, the SFM4300 is the preferred choice. The SFM4200 sensor is highly resistant to pressure, it guarantees reliable measurements at surges of up to 8 bar. Its signal processing time is 0.5 ms, making it incredibly fast and accurate. Customers also benefit from an expanded measurement range of up to 160 liters per Minute.

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Specification

Gas flow
Full scale flow rate
0 - 20
0 - 20slm
Typical accuracy
±2% m.v.
±2% m.v.
Calibration
Air, O₂, N₂O and mixtures thereof
Air, O₂, N₂O and mixtures thereof
Sensor output
Flow and T
Flow and T
Maximum operating pressure
7
7bar
Fluidic connector ports
O-ring
O-ring
Generic
Supply voltage
3 - 5.5
3 - 5.5V
Max. supply current
10000
10000uA
Interfaces
I²C
I²C
Size (LxWxH)
64.5 x 26 x 26.6
64.5 x 26 x 26.6mm

Downloads

Datasheet SFM4300

05/2022

File

1.2 MB

Datasheet05/2022PDF1.2 MB
Selection guide gas flow sensors

06/2025

File

449.9 KB

Application note06/2025PDF449.9 KB
STEP file SFM4300

File

6.8 MB

Drawings/CADZIP6.8 MB
Reference and flow conversions

09/2021

File

293.7 KB

Application note09/2021PDF293.7 KB
Reference and flow conversions calculator

File

30.3 KB

Application noteXLSX30.3 KB
Engineering guide SFM

01/2021

File

592.1 KB

Guide01/2021PDF592.1 KB
SEK-ControlCenter (all devices)

Link

SoftwareLink
Calibration certification gas flow sensors

01/2023

File

169.8 KB

Certificate01/2023PDF169.8 KB
REACH and RoHS declaration SFM/SGM

01/2025

File

122.8 KB

Certificate01/2025PDF122.8 KB
Gas flow sensors brochure

01/2024

File

497.6 KB

Flyer01/2024PDF497.6 KB
  • All products
  • Gas flow sensors
  • SFM4xxx

Sensor evaluation

Buy the following products to evaluate this sensor

NameDescriptionSeriesCategory
SEK-SensorBridgeConnecting bridge with two sensor portsSEK-SensorBridge
SEK-SFM4300-20-PGas flow sensors evaluation kit SFM4300SEK-SFMxxxxGas flow sensors

SEK-SensorBridge

Connecting bridge with two sensor ports

SEK-SensorBridge

SEK-SFM4300-20-P

Gas flow sensors evaluation kit SFM4300

SEK-SFMxxxx

Gas flow sensors

Download the respective viewer software to start measuring

Go to download center

Start testing our sensors fast and easy with the evaluation kits

How to get started

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Sensirion's sensor solutions are used in a wide range of applications and markets. Our reliable environmental and flow sensors improve energy efficiency, increase health and ensure safety and comfort.

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