Absolute humidity is the amount of water vapor contained in the atmosphere, it shows the mass of water vapor per unit volume(g/m³). Use units of grams per cubic meter or pounds per cubic feet. This value varies with atmospheric pressure, so it is not often used in engineering.
The mass of water vapor per unit volume of gas, and absolute humidity means the density of water vapor content. Absolute humidity uses grams per cubic meter or pounds per cubic feet. This value varies with atmospheric pressure, so usually it is not used in engineering.
Relative humidity of air is defined as the ratio of the vapor pressure of air to its saturation vapor pressure.
At temperatures above the boiling point, the atmospheric pressure is equal to the vapor pressure of the water because the water pressure replaces the pressure of all other gases in the enclosed space.
Therefore, the saturation pressure cannot be greater than atmospheric pressure because the relative humidity cannot exceed 100% at temperatures above 100℃.
Therefore, at a temperature of 100°C at normal atmospheric pressure, the relative humidity is 100%, and at 200°C, it is only 6%.
The pressure of water vapor is maximum or the temperature of saturated steam.
In other words, when a mixture of gas-water vapor is cooled under constant pressure, it is defined as the temperature at which frost or ice is produced, meaning the temperature at which the relative humidity is 100%.
When the temperature is lowered to the dew point, the air is saturated, resulting in fog, dew, or frost.
Our humidity sensor is “Capacitive Humidity Sensor”. Humidity is measured through relative humidity, which expresses the amount of water vapor in the air compared to the maximum amount of water vapor at the current temperature.
He unit used is %RH. Humidity Sensor is widely used as a Temp/Humidity Sensor that can measure the temperature by using the electrical properties that change as water molecules are absorbed.