The maintenance of portable oxygen analyzers should be carried out in combination with the instrument structure and usage scenarios, according to the following points:
1、 Daily cleaning and appearance inspection
1. Surface cleaning: Wipe the outer shell with a soft dry cloth every week, avoiding the use of corrosive solvents (such as alcohol) to prevent damage to the sensor or circuit.
2. Air inlet inspection: Ensure that there is no dust or oil blockage that affects gas sampling.
3. Sealing verification: Check if the interface is loose to prevent measurement errors caused by air leakage.
2、 Special maintenance of sensors
1. Electrochemical sensor
Avoid prolonged exposure to high concentrations of oxygen (>1000ppm) or corrosive gases to prevent electrode poisoning.
Regularly check the status of the electrolyte, and if the liquid level is below the scale line, supplement with specialized electrolyte.
2. Zirconia sensor
Ensure a smooth temperature rise during startup, and turn off the power after the temperature drops to room temperature to prevent ceramic components from cracking.
Check the resistance of the heating wire every week, and replace it if the deviation exceeds ± 10%.
3、 Maintenance of pneumatic system
1. Blowing and Cleaning
Before starting up daily, blow the gas path with high-purity nitrogen (99.999%) for 5-10 minutes to remove residual moisture or impurities.
Check the pipeline for aging and damage every week, and replace the sealing gasket or pipe when there is a leak.
2. Preprocessing components
Replace the filter in a timely manner when it is clogged (such as PTFE filter element), and regenerate or replace the desiccant if it fails.
4、 Calibration and functional testing
1. Regular calibration: Use standard gas (such as high-purity nitrogen) for zero and range calibration every 3-6 months, and shorten high-frequency equipment usage to 1-2 months.
2. Response testing: When abnormal data or delayed response is detected, immediately check the sensor status.
5、 Battery and Storage Management
1. Battery maintenance: Charge promptly when the battery level is below 20%, and charge and discharge every 3 months when not in use for a long time.
2. Storage environment: Keep in a dry and ventilated place, avoiding high temperatures, corrosive gases, or strong vibrations. Remove the battery when not in use for a long time.
6、 Other precautions
1. Avoid severe vibrations (especially paramagnetic sensors) to prevent magnetic circuit deviation.
2. Wetting bottles (if any) should be soaked and cleaned with vinegar every 3 days to prevent microbial growth.