Four precautions for the use of combustible gas detectors to avoid improper operation and decreased sensitivity
The use process of the gas detector is relatively simple, but many on-site operators do not follow the correct operation and use steps in the specific use process, resulting in a decrease in the sensitivity of the combustible gas detector and large errors in accuracy. So what are the precautions for using the combustible gas detector?
1. Pay attention to regular calibration and testing
Toxic and harmful gas detectors are the same as other analysis and detection instruments. They are measured by relative comparison method: first, a zero gas and a standard concentration gas are used to calibrate the instrument, and the standard curve is obtained and stored in the instrument. When measuring, the instrument compares the electrical signal generated by the concentration of the gas to be measured with the electrical signal of the standard concentration, and calculates the accurate gas concentration value. Therefore, zeroing the instrument at any time and frequently calibrating the instrument are essential tasks to ensure the accuracy of the instrument measurement.
It should be noted that many gas detectors can replace the detection sensor at present, but this does not mean that a detector can be equipped with different detector probes at any time. Whenever the probe is changed, the instrument must be recalibrated in addition to the sensor activation time. In addition, it is recommended to test the response of the standard gas used for the instrument before using it to ensure that the instrument really plays a protective role.
2. Pay attention to the detection interference between various sensors
Generally speaking, each sensor corresponds to a specific detection gas, but any gas detector cannot be absolutely specific. Therefore, when selecting a gas sensor, it is necessary to understand the detection interference of other gases to the sensor as much as possible, so as to ensure its accurate detection of specific gases.
3. Pay attention to the life of various sensors
All kinds of gas sensors have a certain service life, that is, life. Generally speaking, in portable instruments, LEL sensors have a longer life span, which can generally be used for about three years; photoionization detectors have a life span of four years or longer; electrochemical specific gas sensors have a relatively short life span, generally one to two years; oxygen sensors have the shortest life span, about one year. The life of the electrochemical sensor depends on the dryness of the electrolyte, so if it is not used for a long time, sealing it in a lower temperature environment can prolong its service life. Due to the relatively large size of the fixed instrument, the life of the sensor is also longer. Therefore, it is necessary to test the sensor at any time, use it within the validity period of the sensor as much as possible, and replace it in time if it fails.
4. Pay attention to the concentration measurement range of the detection instrument
All kinds of toxic and harmful gas detectors have their fixed detection range. Only when the measurement is completed within its measurement range can the instrument be accurately determined. If the measurement is performed beyond the measurement range for a long time, it may cause permanent damage to the sensor.
