Precise understanding of knowledge and behavior of the SRM is needed for the development and verification of advanced control algorithm. An fully-automated measurement system is proposed in this paper to identify the magnetization characteristics of the SRM as functions of the winding current and rotor position. The proposed system can characterize the SRM automatically and take magnetic nonlinearity and static iron losses into account. The post-mortem data processing with a graphical user interface constitutes the measuring procedures and provides easy manipulation and clear presentation of the results. The theoretical sensitivity is derived; error sources and uncertainties of the measurement are also analyzed and discussed. Experimental results with good accuracy conducted on a four-phase SRM show the correctness and practicability of the presented system. Special emphasis is oriented on the suitability for the production line application to on-line determine the saturation behaviors of the SRMs.