Help Center

Search the Help Center

LEL-MPS Sensor Behavior

The Molecular Property Spectrometer (LEL-MPS) is a solid-state sensor that detects combustible gases. It classifies gases based on their molecular properties and does not require routine span calibration.

This sensor exhibits the following key behaviors:

Not suitable for low-oxygen environments: Accuracy decreases significantly below 18% oxygen. Use is not recommended when O₂ levels are under 10%.

Clean-air Startup Required: Devices prompt the user at startup to confirm that they are in a clean-air environment. If the prompt is not acknowledged within 15 seconds, the device enters a latched notification state and must be restarted.

Manual Zeroing: Automatic zeroing requires user confirmation. If the clean air prompt is disabled in Blackline Live, the device prompts the user to perform a manual zero.

Calibration Options:
  • Default calibration validates performance without adjusting the sensor's output.
  • Full calibration includes a span adjustment but may affect the accuracy of other gases. This option should be used only by advanced users.

Gas Mixture Requirements: Calibration and bump test gases must contain at least 18% oxygen to avoid negative impacts on sensor accuracy.

Interference resistance: MPS sensors are not affected by electromagnetic interference (EMI) and are resistant to common contaminants that degrade traditional LEL sensors.