Dew point is the temperature at which air cooling occurs to condense the water vapor inside it into frost or dew. The water vapor saturation limit or maximum amount of water vapor for the air to preserve at any given temperature. Condensation occurs when one adds more water.

The compression of air increases the pressure on the water vapor hence leading to the dew point. When one is bleeding the atmospheric air before estimating the measurement, it is usually essential to consider the pressure causing the formation of the dew point. 
There is a difference between the dew point in the process and the dew point at the measurement point.

How to measure dew point

The first common way of measuring dew point is by observing a bathroom mirror that steams up when the temperature is equal during the shower. The dew point measurement is usually connected to humidity and meaning, and the dew point increases with an increase in the humid air.
Industrial measurements of dew point that includes compressed air systems, drying processes, and air pressure pipelines require a dew point sensor, the technological piece for taking the temperature at which water vapor saturates air sampling.

Hygrometer Instrument

The known point dew point sensor is a hygrometer, an instrument that contains a narrow light beam, a small mirror, and a light detector. The light beam gets reflected into the detector and off the mirror, which helps estimate the reflected light’s brightness. There is always dew formation on the mirror when there is a cooling effect to the dew point temperature.
The reflected light beam becomes less bright due to light blockage reaching the detector by the water droplets on the chilled mirror. There is an indication of the mirror being at the dew point when the measured reflected light decreases.

Psychrometer Instrument

Another instrument for dew point measurement is a psychrometer. It contains two thermometers known as a wet-bulb thermometer, and it has a wet wick around its bulb. When the water off the wick evaporates, it leads to the removal of heat from the thermometer.
The dew point determines the evaporation rate at which there is a reduction in the temperature of the wet-bulb thermometer. One has to ventilate the thermometers with a fan or a whirling device. The wet-bulb temperature takes a few minutes to be stable at a specific temperature.

You will need to use a chart for the conversion of the temperature difference between the two thermometers. The best dew point sensor helps get high accuracy and quality services on the measurement and calculation of dew point. It also improves operational efficiency and can prevent malfunctions, thus leading to optimum working sufficiency.

Conclusion

Monitoring the dew points helps prevent problems like freezing and contamination of pipes due to condensation, pipe blockage and machinery breakdown, etc. Ensure that you choose the best dew point sensor and install it correctly for accurate measurement.