Physical desiccation, humidity is how to capture and control?

          Cabinets physical style is the use of mechanical air sampling humidity sensors and mechanical comparator preset humidity chamber , suction action agency by the tide gate memory alloy spring , return spring and rod composed of IC timer control dehumidification program , using pointer hygrometer inside the current humidity.

          The so-called mechanical type humidity sensor , the length variation is primarily a humidity sensor. The principle is : stretched on a metal bracket on the strong hydrophilic nylon plastic film , when the ambient humidity rises plastic shrink film will absorb moisture like cotton shorten the length of taut , oppression micro switch button power to make Cabinets work . When the humidity drops plastic film will stretch relaxation , release the button and micro switch off , so Cabinets stop working. Driven by a rotary control knob plastic film eccentric compression micro switch position, which is the baseline pressure is adjusted to achieve turning on or off when the control knob is rotated to the wheel position on behalf of a range of humidity power , in order to achieve the purpose of controlling the humidity inside . Because of this mechanical humidity sensor must be in on the natural evaporation of moisture absorption or to a certain extent , in order to generate the necessary power to activate or deactivate the micro switch, and therefore unresponsive, the lag time can be up to one or even twenty minutes , you can not timely response to changes in humidity . The small amount of water can occur change of the reaction , and the environmental impact of plastic film that is large , a large value of the control point of drift , so that the humidity sensor using Cabinets , since the error of up to ± 10%, only the " high, low "or " L, H "( i.e., low, high ) to control the humidity inside , and a specific humidity value can not be adjusted to set the desired humidity. Further, since the plastic film material itself instability , easy to aging deterioration, affect life expectancy.