The functional relationship between the absolute error and the parameter values of a voltage output accelerometer is presented in this paper. The theoretical basis for the mathematical model of the accelerometer and its standard, which is a reference for the error determination, is discussed. The polynomial function is applied for error approximation. Optimal orders of the polynomial along with their parameters and associated uncertainties are determined. The results presented in this paper concern the maximum errors obtained by exciting the accelerometer by the signal of constrained magnitude.