Calibration and maintenance

What this track covers

An analyser that was right on the day it was installed is not automatically right a year later. This track explains what calibration really does, which gases to use, how often to check, how to diagnose a reading that looks wrong and how to keep the records a quality system expects.

Lessons, in order

1. How gas analyser calibration works: zero and spanCalibration compares the analyser's reading with a gas of known concentration and adjusts it to match.Beginner4 min
2. Calibration gases: choosing, handling and certificatesChoose span gas near 70 to 90 % of the range in a balance gas that matches the sample, with a certificate stating concentration, uncertainty and expiry.Intermediate3 min
3. How often should you calibrate a gas analyser?Set the interval from three things: how much error the process can tolerate, how fast the analyser drifts, and what a wrong reading costs.Intermediate3 min
4. Auto-Calibration and validation checks for gas analysersAuto-calibration switches zero and span gas to the analyser by solenoid valves on a timer, keypad or Modbus command, and adjusts or records the result.Intermediate3 min
5. Troubleshooting gas analyser readings: high, low, noisy, slowApply known gas at the analyser inlet.Intermediate3 min
6. Maintenance schedule and spares for gas analysersMaintain analysers by routine: a daily look at flow, pressure and condensate; a weekly check of filters and drain; a monthly calibration check; and an annual full calibration, sensor check and leak test.Intermediate3 min
7. Sensor life, poisoning and replacement in gas analysersElectrochemical cells are consumed by the gas they measure and last months to years depending on exposure.Intermediate3 min
8. Records, audit trails and qualification for regulated plantsRegulated plants must show that an analyser was fit for purpose and stayed so: traceable calibration records, alarm and fault history, controlled access to settings, change control, and documented qualification (installation, operation and performance).Advanced3 min

Next track: Safety and hazardous areas