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How to plan calibration and manage water-quality sensor drift
Prepare verification, calibration and replacement procedures for instruments in water treatment service.
HOSON WATER editorial ·
Classify instruments by their operating role
Separate sensors used for release or automatic protection from sensors used for trends and troubleshooting. Agree on verification methods and calibration intervals using the manufacturer’s instructions, service conditions and site procedures. Put service access, consumables and replacement leads in the instrument list before the owner accepts the package.
Record what changed during maintenance
Capture the reading before adjustment, reference solution or comparison result, work performed and final reading. A record of repeated drift can reveal contamination, reference depletion, sample conditioning problems or a sensor approaching replacement. Link the maintenance record to the historian so the team can distinguish a real process change from a calibration event.
Keep controls safe while a sensor is serviced
Define how the plant identifies maintenance state, suppresses misleading trends and routes any necessary alarm. If a measurement provides an interlock, agree on approved operating procedures or substitute measurements before removing the device from service. Verify that the system returns to the expected protection state after maintenance.