7/88 3.2.1 Meaning of Static Calibration 3.Standard A standard for a certain physical variable is often "just another" measuring device for that variable but with higher accuracy than the instrument to be calibrated. Primary Standards are considered the "state of the art",that is,the most accurate way known to measure the quantity of interest. Primary standards are developed,maintained,and improved by national laboratories as well as some large,high-tech,companies. They may also provide calibration services. ◆Lower Level standards(secondary,.tertiary(第三的)，eto)are available for calibration services at national laboratories, commercial calibration laboratories,and in-house calibration laboratories associated with industrial companies,university laboratories,etc. 8/88 3.2.1 Meaning of Static Calibration 4.Calibration Procedure ①Examine the construction(构造)of the instrument,and identify and list all the possible inputs. ②Decide,as best you can,which of the inputs will be significant(显著 的；重要的)in the application for which the instrument is to be calibrated. 3Procure[Obtain (something),esp.with care or effort]apparatus (仪器；器械；装置)that will allow you to vary all the significant inputs over the ranges considered necessary.Procure standards to measure each input. 4By holding some inputs constant,varying others,and recording the output(s),develop the static input-output relations.3. Standard ‹ A standard for a certain physical variable is often “just another” measuring device for that variable but with higher accuracy than the instrument to be calibrated. ‹ Primary Standards are considered the “state of the art”, that is, the most accurate way known to measure the quantity of interest. ‹ Primary standards are developed, maintained, and improved by national laboratories as well as some large, high-tech, companies. They may also provide calibration services. ‹ Lower Level standards (secondary, tertiary( 第三的 ), etc) are available for calibration services at national laboratories, commercial calibration laboratories, and in-house calibration laboratories associated with industrial companies, university laboratories, etc. 3.2.1 Meaning of Static Calibration 7/88 4. Calibration Procedure ① Examine the construction(构造) of the instrument, and identify and list all the possible inputs. ② Decide, as best you can, which of the inputs will be significant(显著 的；重要的) in the application for which the instrument is to be calibrated. ③ Procure[Obtain (something), esp. with care or effort] apparatus (仪器；器械；装置) that will allow you to vary all the significant inputs over the ranges considered necessary. Procure standards to measure each input. ④ By holding some inputs constant, varying others, and recording the output(s), develop the static input-output relations. 3.2.1 Meaning of Static Calibration 8/88