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Digital Gas Flow Sensor



  • High Accuracy of +-2% of reading (or 0.05 SLPM)
  • 2 Millisecond Response time
  • I2C Digital Communication to Read Flow or Temperature, and Change Preferred Settings
  • Temperature Compensating
  • Microcontroller Design for Customization

P/NPriceDelivery Time
KPI-DMFS-1$190.005 Days

Kelly Pneumatics, Inc. offers a Gas Flow Sensor for high volume flow rates of Air and Oxygen. The sensor automatically compensates for temperature changes in the measured gas and outputs accurate readings of mass flow and temperature via analog voltage.

The Gas Flow Sensor outputs flow for Air and Oxygen from 0-300 SLPM, with an accuracy of 2% of reading, and offers a flow sample response time of 2 milliseconds. An internal microprocessor measures signals from an internal thermistor and hot wire anemometer to linearize flow measurements, and allows for numerous settings for flow and temperature output readings. The compact, lightweight design is perfect for OEM applications, especially medical, semiconductor, and gas analyzer products.

Digital Communication

The unit has an internal microprocessor which can be used to dynamically change settings. Digital Commands allow switching between flow measurements in either Air or Oxygen, as well as reading the current gas temperature. I2C commands can also change the units of flow measurement between Standard Liters per Minute (SLPM) or Pound Mass per Minute (lb/min). These preferences can also be saved to internal EEPROM to avoid initialization on startup. Using a microcontroller also means custom software versions are available per your application’s requirements. For more details, see Application Note “I2C Details for KPI-DMFS-1” below.


Supported Media Air and Oxygen
Flow Range 0 to 300 SLPM
Flow Accuracy 2% of reading or 0.05 SLPM, whichever is greater, at 70 °F and 14.7 psia
Flow Sample Rate 2 milliseconds
Temperature Measurement Range 0 to 50 °C (0 to 122 °F)
Temperature Measurement Accuracy ±1 °C (±1.8 °F) at flows >1 SLPM
Maximum Allowable Atm. Pressure 400 kPa (58.0 psia)
Port Sizes 19 MM Male (Standard), 3/8″ Female NPT (with adapter block/bracket)
Power Requirements 5 volts (0.785 Watts Max Power Consumption at 300 SLPM)
Operating Temperature 0 to 50 °C (0 to 122 °F)

Pin Layout (Digital Output Version)


Pin Number1234
FunctionI2C DataGroundSupply Voltage I2C Clock


(All Dimensions in Inches)


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Purchasing Information

After completing your order, you will receive an email confirmation, as well as a shipment tracking number when your order has shipped.

Payment: We accept PayPal Account payments and most major credit cards. Phone orders are also accepted.

Refund Policy: Give it a try! We offer a 30-Day refund period for all orders. If you ship back the order and confirm your return is in transit within 30 Days of receiving the order, we will refund the cost of units ordered. This refund does not include parts that are damaged by you or missing components. All shipping costs are non-refundable unless the package was incorrectly shipped or you received defective products.

Cancellations: You can cancel your order for a full refund If your order hasn’t shipped. Contact us and submit your order number to request a cancellation.

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