Keeping a specific dew point is the requirement for a trouble free plant operation. The mobile dew point measuring instrument DP 300 is the ideal service instrument in a handy case. It measures relative humidity, temperature, and the dew point up to 50 bar, easy, fast, without an annoying cable. With the PC software the measured data can be recorded in an Excel file and further parameters can be selected: ppm, g/kg, mg/m3, atmospheric dew point.