Explanation of the Faults of Gas Detectors
There is no measured gas in the air, but the values fluctuate greatly or jump.
A zero-point variation range within less than 1% of the maximum measurement range in a short time is within the normal range. A long-term drift of less than 2% of the maximum measurement range when no gas is being measured is also within the normal range. When exceeding this range, it is necessary to confirm whether there is the measured gas at the site. If the temperature and humidity in the air change greatly, the values will be unstable.
Confirm whether the gas detector has carried out zero-point calibration or target-point calibration operations. If there is the detected gas, the
zero-point calibration operation may not be able to detect low-concentration gases. If there is the detected gas, then carry out the target-point calibration. However, if the calibrated concentration value is inconsistent with the actual concentration value, the values of the gas detector will fluctuate greatly or the detected values will become smaller.
If the problem still cannot be solved, confirm whether the gas detector has been exposed to high-concentration gas or the gas sensor has been impacted by high-concentration gas. If the gas sensor is impacted, after the gas sensor is activated and aged for 24 hours, if the values are still unstable, the gas sensor may have been impacted and damaged, and it is necessary to replace the gas sensor.
Low-concentration gases cannot be detected.
Check whether the air pump of the gas detector is working normally. Block the air inlet with your finger for 5 seconds. If it is normal, you should feel an obvious suction force. If there is no suction force, check whether the air inlet is blocked.
Calibrate the zero point by passing nitrogen or in clean air, and then check after calibration.
After calibrating the zero point, if the measured gas cannot be detected, it is necessary to restore the gas detector to its factory settings.
After all the above steps have been carried out but the gas still cannot be detected, it is necessary to confirm whether there is the measured gas at the site, or the concentration of the measured gas is indeed very low, and it cannot be detected if it is lower than the minimum detection accuracy of the gas sensor.
