Ceramic humidity sensor consists of a metal oxide ceramics , separate sub -type and E- types

Ceramic humidity sensor resistance at low humidity segment larger resistance change with humidity at 40% -80% RH range, good linearity , high humidity segment the change is too small, visible ceramic humidity sensor in the normally wet state with good the characteristic curve segment in the high humidity , low humidity curve in distortion , nonlinear obvious. German ceramic humidity sensor sensing property also affected by temperature changes, temperature compensation of the measurement accuracy is important. Engine Water Temperature Sensor are alumina, a synthetic magnesium oxide ceramic humidity sensor element increases and decreases the conductivity , the surface of the oxide molecular chemisorption formed , N -type semiconductors , P -type semiconductor oxide to a positive humidity, moisture characteristics and negative characteristics . Alumina, magnesia , Coolant Temp Sensor , the temperature at below 700 ℃ moisture measurements can be made more stable . But the structure is complex and requires heating the grating is heated to 700 ℃, power-intensive use of harsh conditions , the price is expensive, but also to prevent changes in air flow characteristics cited changes , not universal use in the industrial field . Ceramic humidity sensor in recent years to develop a new type Shaft Position Sensor. Advantages humidity lag , fast response , small size , easy to mass production, but because of porous material, a great impact on the dust , routine maintenance frequently , often need to be cleaned easily electrically heated affect product quality , affected by humidity , the humidity Linear temperature environment is poor, especially short life , long-term reliability is poor, the humidity sensor is such an urgent problem.