Automotive Mass Air Flow Sensor (MAFS) Test Stand: ManualProduct Summary

The manual version of the Automotive Mass Air Flow Sensor (MAFS) Test Stand is an air flow measurement test stand designed for setting and measuring the mass flow rate of through Mass Air Flow Sensors and other induction components.

Key Features
  • Mass flow range: 1.5 – 0.00098 lbm/sec (694 – 0.5 gps) ±0.65% of reading
  • Highly repeatable results (less than ±0.25%)
  • Least automation and highest uncertainy of the three Mass Air Flow Sensor Test Stands
How does this test stand work?

The operator manually opens the nozzles via included toggle switches labeled with estimated mass flow. The FC175 Flow Computer calculates the Mass Flow and displays Unit Under Test voltage and ambient test conditions (T and RH, P optional). The system utilizessonic nozzles which are installed in a common plenum and the test setup is shown in the following diagram:

Related Products for Varying Levels of Automation & Uncertainty

For information on related test stands, refer to the Mass Air Flow Sensor Test Stand Product Comparison.

Traceable to NIST

All Flow Systems air test stand sonic nozzles and instruments are traceable to National Institute of Standards and Technology (NIST).

System Specifications

The manual version of the Automotive Mass Air Flow Sensor (MAFS) Test Stand has the following specifications:

Specification Value(s)
Mass Flow Rate 0.00098 – 1.5 lbm/sec, ±0.54% of reading
0.8 – 1225 scfm, ±0.65% of reading
0.5 – 694 gps, ±0.65% of reading
1.6 – 2498 kg/hr, ±0.65 of reading
Flow Measurement Flow Controller FC500-FC
Repeatability Less than ±0.25%, defined as 2 standard deviations divided by the mean of 20 samples
Unit Under Test (UUT) Voltage 0 – 5 VDC, ±0.02% Full Scale
0 – 10 VDC, ±0.02% Full Scale
Unit Under Test (UUT) Frequency (Optional) 100 – 20 kHz, ±0.01 Hz
Unit Under Test (UUT) Pressure (Optional) 0 – 15 psia, ±0.05% Full Scale
Unit Under Test (UUT) Temperature ±0.5°F
Unit Under Test (UUT) Differential Pressure 0 – 60 inH2O (optional)

Uncertainty Analysis

For information on uncertainty analysis for this equipment refer to Uncertainty Analysis in Gas Flow Measurement When Using Sonic Nozzles.


National Instruments LabVIEW Logo
Control System Operator Interface

This test stand uses the FC175 Flow Computer for mass flow measurement. The controller software for the FC175 must be installed on a customer-supplied workstation and is used to operate the FC175. The FC175 can not operate as a stand-alone device. Controller software is written using National Instruments LabVIEW™.

Configure Software for Testing & Meter Calibrations
  • Configure a test by specifying: meter type, fluid state, fluid type, number of meters, units, time base, standard pressure and temperature, and measurement stability criteria
  • Configure a meter calibration by specifying a variety of input parameters in order to calculate discharge coefficient (Cd) as a function of throat Reynolds Number
Monitor & Log Measured Flowrates
  • Data is logged to the connected customer-supplied workstation
  • Data may be logged automatically or at a user-defined interval
  • Data can be plotted (all parameters simultaneously) in real-time
  • When connected, the CFV pattern can also be controlled in real-time
  • Iterative solution for Discharge Coefficient (Cd) based on actual calibration data or theoretical models
Customize Controller Software and Integrate Data
  • Controller software can be customized to fit a wide variety of customer needs
  • Data can be integrated with customer’s local databases and/or information systems
Configure Instrument Calibration Settings
  • Enter calibration coefficients for each instrument connected to the FC175 (i.e. pressure transducers, RTD’s, and dew point transmitters)
  • Coefficients can be generated then saved to file, which can then be associated with instruments
Flowrate Calculations Meet ASME Standards
  • Calculations for sonic nozzles are in accordance with ASME MFC-7M / ISO 9300
Additional Software Screenshots
Instrument Calibration Screen

Instrument Calibration

Test Setup Screen

Test Setup

Meter Calibration Screen

Meter Calibration

Data Monitor

Data Monitor

Facility Requirements

The following facility requirements, which are to be supplied by the customer at the installation site, are needed for all three versions of the Automotive Mass Air Flow Sensor (MAFS) Test Stands:

  • Shop Air: 5scfm, 70 to 120 psig, 60 to 90°F; Pressure Dewpoint < 39°F; Particulates: < 5 microns; Oil Content: < 10ppm
  • Electrical Power: 100-240 VAC / 50 to 60 Hz / 1pH / 7.5 to 15 A
  • Vacuum: 2114 acfm at 12.3″ Hg based on previously defined mass flow range

Photos & Schematics

Additional Software Screenshots

The following are pictures and schematics of the Automotive Mass Air Flow Sensor (MAFS) Test Stand: Manual Model.

(Image No.1)

Mass Air Flow Sensor Semi-Automatic (Image No.1)