Vaisala devices automatically perform quality checks to ensure reliable data. When measurements are marked invalid, it's usually for one of these reasons:
Sensor stabilization period
AQT530 and AQT560 sensors connected to BWS500 weather stations automatically reject gas measurements for the first 24 hours after a restart. This allows the sensor to stabilize for accurate readings.
Hardware issue
Invalid readings may indicate a hardware problem. Contact helpdesk@vaisala.com to check your Health index value. If the value is 0, your electrochemical gas cells need replacement. You can order new cells through Vaisala Sales.
Next steps
Check your device documentation for other scenarios that trigger invalid measurements or contact our support team for assistance.