The automatic dew point measurement instrument Dewchecker 3.1 is a portable device used for measuring the dew point temperature of gases.

Per definition, the dew point is the temperature of a body at which the water vapors start to condensate on its surface, respectively the balance adjusted between condensing and evaporating water. The level of the dew point depends on the moistness of the measuring gas. Due to the direct measurement of the dew point temperature, the measurement is accurate and long-term stable. With this device, it is possible to measure dew point temperatures lower than the ambient temperature. Moreover, the device itself requires very low maintenance.

Dewchecker 3.1 measures the dew point value completely automatically. A beam of light, from the emitting diode, is aimed at the mirror’s surface and a photodetector monitors the reflected light. The Mirror is constructed from a material with good thermal conductivity and it is cooled down by using a thermoelectric cooler until the condensation begins. As the amount of reflected light decreases, due to the absorption, the photodetector output decreases also. An internal control system monitors the mirror’s temperature at the dew point level over reflected photodetector voltage.