Evolution in calibration of electronic non-automatic weighing instruments

Electronic weighing instruments consist of a load receptor, an electromechanical converter, an electronic processing unit, a display and an interface. The object of the calibration is the indication provided by the instrument in response to an applied load. The results are expressed in units of mass. When is not possible to use only standard weights, the substitution loads may be used. With each substitution step however, the uncertainty of the total test load increases substantially more than if it were made up of standard weights only, due to the effects of repeatability and resolution of the instrument.