My new pressure sensor system is giving unexpected readings. How can I determine if the problem is with the voltage output pressure sensor or my data acquisition (DAQ) system?
A systematic troubleshooting approach is the most effective way to isolate the source of error in an instrumentation loop. By separating the sensor from the rest of the system, you can determine if the fault lies with the measurement device or the signal processing hardware. Here is a step-by-step diagnostic guide based on industry best practices.
Featured voltage output pressure sensor products
DMP331P Hygienic Flush Pressure Transmitter - Sanitary pressure sensor wth exposed diaphragm with no crevices for high temperatures up to 300 Degrees Celsius in ranges from 100mb up to 40 bar gauge or absolute
Water pump input/output testing pressure sensor with 30 psi absolute range - Absolute pressure sensor for water pump testing with 30 psi range, 0-10V output, G1/4" male process connection, and Viton seal. Ideal for measuring positive pressure and vacuum.
Verify System Basics:
- Power Supply: Ensure the voltage supplied to the sensor is within its specified operating range.
- Wiring: Double-check that the electrical connections are correct.
Isolate and Test the Sensor:
- Disconnect the sensor’s signal wire from your DAQ, PLC, or display.
- Using a calibrated digital voltmeter (DVM), measure the voltage directly across the sensor’s signal output. This provides a direct, unfiltered reading of the sensor’s output.
Perform a Bench Test with a Calibrated Source:
- Connect the sensor to a known, stable pressure source, such as a pressure calibrator or deadweight tester. This allows you to apply precise pressures and validate the sensor’s response.
- Create a data table, recording the sensor’s direct voltage output (from your DVM) at several pressure points across the measurement range (e.g., 0%, 25%, 50%, 75%, and 100% of full scale).
Featured pressure calibration products
High Pressure Range Calibrators - High range pressure calibrators for checking and testing the accuracy performance of high pressure measurement instrumentation.
Suction Pressure Calibration Equipment - Select a calibration equipment for calibrating suction pressure measuring devices, and generating suction pressure for setting calibration points.
Compare Measured Data to Specifications:
- Calculate the ideal output for each pressure point.
- Factor in the sensor’s allowable tolerances. This includes the accuracy, and the specified zero & span offset range.
- If your DVM readings fall within the calculated range of ideal output plus/minus the combined tolerances, the sensor is performing correctly.
Investigate the Data Acquisition System:
- If the bench test confirms the sensor is healthy, the problem lies downstream in your signal processing chain.
- Input Range: Confirm your DAQ card or PLC analogue input is configured for the correct voltage range.
- Software Scaling: Check the scaling factors used in your software or PLC logic to convert the voltage reading back into a pressure value (e.g., bar, psi). Incorrect scaling is a very common source of error.
By following this process, you can confidently determine whether the issue originates from the voltage output pressure sensor or the instrumentation used to read it.
Featured voltage output pressure sensor products
ATM/T Pressure and Temperature Dual Output Transmitter - Dual analogue output signal transmitter for simultaneous measurement of media pressure and temperature. Pressure 100mb - 1000bar and temp -25 - 100 DegC.
DS210 Combined Low Pressure Switch, Indicator and Sensor - Low range three in one pressure switch, pressure indicator and pressure sensor for use on pneumatics and HVAC applications.
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- 4 Wire
- Cardinal Points
- Isolation Diaphragm
- Primary Pressure Reference Standard
- Secondary Pressure Standard
- Stainless Steel Pressure Sensors
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