Development of a virtual instrument for humidity measurement

In this paper is developed a flexible virtual instrument using LabVIEW for relative humidity measurement. The resulting virtual instrument eliminates the disadvantages of traditional measuring instruments whose functions cannot be changed by the user according to their needs, predefined by the manufacturer. Data acquisition interface (virtual instrument) was made in LabVIEW and give user the possibility to measure humidity, setting a reference value, compare the measured value with reference value and signaling if the comparison result is true. Also, the user has the possibility to visualize on a graph the humidity values, save them and to select one up to 15 physical channels. Measured values can also be seen as a table registered during the acquisition period. The output of humidity sensor is a voltage values which corresponds to humidity value. So, the all acquisition process is reduced to a voltage measurement. Finally, experimental determinations were made in order to verify the functionality of the equipment. Also, in conclusion are pointed out different situations in which the solution can be used.