Low Range Mode

2 0 0 November 3, 2025 November 3, 2025
As the SpanBox5 does not support calibrating analyzers set to Low Range Mode (Cooling Tower), you have to calibrate manually if attempting to calibrate while in Low Range Mode.
 
Once in Low Range Mode, the following conditions apply:

  1. Filter Detection must be off.

  2. Must calibrate 0, 5, and 10 in order.

  3. Max PPM will be ~100 ppm. No calibration point over 50 ppm should be used.

  4. Apply the calibration gasses for 30 seconds.

  5. SpanBox5/Cal5.0 cannot accommodate low range calibration.

  6. Calibration must be done at the sampling point immediately before each test.

  7. Gas must be provided using a constant flow regulator (not on-demand) set to .45 LPM or more feeding a TEE. The probe should attach securely on the middle leg of the TEE.

  8. Each bottle should have a dedicated regulator.

  9. The unit should be out of direct sunlight and protected from extreme changes in the environment. The orientation of the machine should not change. The background should be under 10 ppm.

  10. If the phx42 in question has been used for Method 21 monitoring and is not successfully calibrated in Low Range Mode, it will need to be returned to LDARtools for factory calibration. Request an RMA if this applies.

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Daily Calibration