MQ 4 sensors use a small heater inside with an elector-chemical sensor in order to measure different kind of gases combinations. They can be calibrated, but, in order to do that a know concentration of the measured gas or gasses is needed for that. For industrial purpose calibrations are done in special metro-logy laboratories with accurate probes and tests.
Only logged in customers who have purchased this product may leave a review.
No products in the cart.