Rae QRAE 3 User Manual

Also see for QRAE 3: Quick start guide

Rae QRAE 3 User Manual Manual pdf 38 page image

3510.3. Zero CalibrationThis operation sets the zero point of the sensor calibration curve for clean air. It should beperformed before other calibrations.Note: If you use a zero air cylinder, you must use the QRAE 3 Calibration Adapter (and a Tcalibration tube if the instrument has a pump). Using a calibration adapter is not necessary forcalibration in fresh air.10.3.1. Zero CalibrationThis procedure determines zero points of most sensors. The QRAE 3 should be zero-calibrated inclean air with 20.9% oxygen or with a cylinder of clean zero air.At the Calibration menu, select “Fresh Air” by pressing [Y/+] once to enter fresh air calibration.After a timer countdown, the zero calibration is done. The LCD displays the sensor names andtells you whether each calibration passed or failed, followed by the sensor readings.Note: You can abort the calibration at any time during the countdown by pressing [MODE].10.3.2. Single-Sensor Zero CalibrationSelect the sensor and then start the calibration by pressing [Y/+]. You can abort the procedureanytime by pressing [MODE].10.4. Span CalibrationThis procedure determines the second point of the sensor calibration curve for the sensor.Note: When a manual calibration is performed, the readings shown are in the equivalentunits of the calibration gas, and not the measurement gas.10.4.1. QRAE 3 Pumped ModelThe QRAE 3 pump draws at a flow rate of between 200cc/min and 450cc/min. Theinstrument must be connected to a cylinder of calibration gas with supplied tubingfeaturing a T calibration tube (P/N M02-3008-000), as illustrated below.Note: A constant-flow regulator with flow rates from 500cc/min to 1000cc/min should be used.Note: Make sure pressure inthe calibration gas cylinderis higher than 100 psi whenusing a T calibration tube.