HIM-humidity recorder -Hygrograph - for continuous recording of relative air humidity
A hygrograph is a meteorological measuring instrument for the detection and recording of air humidity in a continuous, temporal course. It is therefore a recording hygrometer that controls a writing arm via its specific input measuring method. This in turn has a writing attachment at its tip, with which it transfers the course of the air humidity or the corresponding humidity measurement to a rotating paper drum and thus displays it graphically. Hair hygrometers are the most frequently used input measurement method and display the course of relative humidity. The time span of the recording is determined by the rotation speed of the paper drum. In weather stations, hygrographs are usually implemented together with a thermograph, which is subsequently referred to as a thermohygrograph.