What are the common faults of gas detectors and how to solve them
Gas detectors are commonly used in industrial production, and corresponding safety protection equipment is used based on their detection results. What are the common faults of gas detectors? How to solve common faults of gas detectors?
Fault 1: Low concentration gas cannot be detected
Solution:
1. Check if the gas pump of the gas detector is working properly. Use your fingers to block the air inlet for 5 seconds. If there is a noticeable attraction, if there is no attraction, check if the air inlet is blocked.
2. Calibrate zero point with nitrogen or in clean air, check after calibration
3. After calibrating the zero point, if the measured gas cannot be detected, the factory settings of the gas detector need to be restored
4. The above steps have been completed, but cannot be detected. It is necessary to confirm whether there is any gas being measured on site, or if the concentration of the gas being measured is indeed very low, and it cannot be detected below the minimum detection accuracy of the gas sensor.
Fault 2: There is no measured gas in the air, but the value changes greatly or jumps
Solution:
1. The range of short-term zero point variation less than 1% of the maximum range is considered normal, while the drift for a long time without measuring gas is less than 2% of the maximum range, which is considered normal. If it exceeds this range, it is necessary to confirm whether there is measuring gas on site. The temperature and humidity in the air fluctuate greatly, and the numerical value is unstable
2. Confirm whether the gas detector undergoes zero point calibration or target point calibration. If there is a detected gas, the zero point calibration operation may not be able to detect low concentration gas. If there is a detected gas, target point calibration will be performed, but the calibrated concentration value is inconsistent with the actual concentration value, and the gas detector's value changes greatly or the detected value decreases
3. If the problem cannot be solved, it is necessary to confirm whether the gas detector has impacted the gas sensor through high concentration gas or high concentration gas. If the gas sensor is impacted and aged for 24 hours, if the value is unstable, the gas sensor may be impacted and damaged, requiring replacement.
Fault 3. Incorrect inspection
Solution:
1. Confirm whether the on-site gas concentration is correct, and there is a significant difference between the theoretical value and the actual value. Use a standard gas calibration gas detector to ensure the accuracy of the detection, or send it to a third-party measuring institution for calibration
2. If the gas sensor is used for a long time, the measurement value may have errors. It is necessary to first confirm with the manufacturer whether the gas sensor can continue to be used. If the sensor itself is close to its service life, it can still be used normally even after being recalibrated for a short period of time, but the measurement value of the gas detector may experience drift detection errors. It is recommended to replace the gas sensor.
Fault 4: Alarm also occurs when the value is 0 or the alarm value is not reached in the air
Solution:
1. Check if the various alarm parameters of the gas detector have been modified
2. Check if the alarm mode and alarm mode of the gas detector have been modified
3. Check if the alarm status of the gas detector is concentration alarm or other fault alarm. The concentration alarm appears with the words A1 or A2, and the red light flashes
4. If the gas detector alarm is caused by human operation modification, it can be resolved by restoring the factory installation. The fault alarm needs to be further checked for short circuits, open circuits, poor contact, sensor faults, etc., or returned to the factory for inspection.
