Steel Conduit and EMT Enclosed Circuits: Analysis and Testing

The performance of electric circuits enclosed in steel conduit or EMT is of great importance for the proper operation of industrial and commercial installations as well as the safety of humans in these facilities. This paper presents a comprehensive modeling procedure for these systems and the verification of these models with extensive testing under various loading conditions. The paper presents the mathematics of the approach as well as the testing procedure, test results and verification of the mathematical model. One important parameter in the model is the magnetization characteristics of the various steel raceway materials. The paper presents an elegant and simple procedure to measure the magnetic properties of the various raceway materials. The validated model is used to compute important design parameters, such as maximum permissible lengths and to assess the performance of specific designs. This work updates the results obtained with a similar but less comprehensive previous approach for modeling these systems.