How to judge the performance of a gas detector?
The performance of a gas detector is mainly judged based on the following aspects:
1. Accuracy, as an important performance indicator of gas detectors, is a crucial factor affecting the accuracy of their measurements. The national standard requires the accuracy of gas detectors to be ± 3% of the full range, and gas detectors with good accuracy can achieve ± 1% of the full range. The higher the accuracy, the better the performance of the gas detector.
2. Sensitivity (reaction time): The sensitivity of a gas detector must maintain undistorted measurement conditions within the allowable concentration range. In fact, the response of a gas detector always has a certain delay, and it is hoped that the shorter the delay time, the better. Gas detectors have high sensitivity and can measure a wide range of gas concentrations. However, due to the influence of structural characteristics, the inertia of mechanical systems is large, and gas detectors with low sensitivity can measure a lower range of gas concentrations. The higher the sensitivity, the better the performance of the gas detector.
3. T90 time refers to the time required for the gas detector to display a concentration value from 0 to 90% of the full range. Of course, the prerequisite is that the gas concentration in the tested environment must always be above 90% of the full range of the gas detector. Otherwise, the gas detector cannot reach T90 no matter what. The shorter the T90 time, the better the performance of the gas detector.
4. Stability refers to the stability of the gas detector's basic response throughout the entire working time, which depends on zero drift and interval drift. Zero drift refers to the change in the reading response of a gas detector during the entire working time when there is no target gas. Interval drift refers to the change in the display reading response of a gas detector continuously placed in the target gas, manifested as a decrease in the display reading of the gas detector during the working time. Ideally, a gas detector should have an annual zero drift of less than 10% under continuous operating conditions. The higher the stability, the better the performance of the gas detector.
5. Consistency (repeatability) refers to the fact that the displayed readings of a gas detector should be very close or even the same after multiple detections in the same testing environment. The better the consistency, the better the performance of the gas detector.
To determine the accuracy of the gas detector, you can use the first and fourth points above. Of course, the gas detector can also be sent to the metrology institute for metrological certification.
