For the MQ-8 hydrogen gas sensor, the data-sheet mentions an “over 48 hour” pre-heat time that is needed for the device to operate accurately and optimally. Is this a 1 time preheating time? And would this mean running electricity through the device for 48 hours, or using a heat-gun or heat-source to heat the parts up?
The data in the data sheet was collected after passing current through the sensors heater pins for 48 hours.
The heater needs to be on to collect data and it’s recommended to “burn in” a new sensor for 48 hours before use. As long as it’s used regularly, one time should be enough but you should allow the sensor to heat up 5 to 10 minutes before each use for the best data.