Abstract: Describes the derivation process and application conditions of two linear measurement models of uncertainty. At the same time, by evaluating the uncertainty of the measurement results of the power consumption in the energy efficiency testing of washing machines, two linear measurement models of the uncertainty and their propagation formulas are applied to calculate with different analysis conditions. It can be found from the calculation results that the different forms of the linear model determine whether the uncertainty component is expressed by standard uncertainty or relative standard uncertainty in the propagation process. On the other hand, in the process of uncertainty propagation, the difference in calculation results may be caused by the existence mode (constant or variable input) of each input value of the mathematical model in the process of uncertainty analysis. Generally, the input with small uncertainty will not affect the result.

Key words: Measurement model, Propagation formula, Uncertainty