The mobile METPOINT BDL portable data logger enables rapid and simple measurement data recording and evaluation of the compressed air quality directly on site. It is a universally implementable hand-held measuring device with an integrated data logger for recording measurement data such as e.g. consumer and through flow measuring, pressure and vacuum measuring, temperature measuring as well as residual humidity and dew point measuring and it translates the process data into clear, unambiguous statistics and graphics. Up to 100 million measurement values with the date and measurement location name can be saved and then represented graphically in coloured measurement curves.