This research focuses on testing single phase distribution transformers under fault condition pole, making nondestructive testing: magnetic particle and liquid penetra nt to the silicon steel sheet, as well as, mechanical stress testing the insulating paper as a continuation research on n on-conventional methods for the analysis of machines with metal components of the electrical industry. With the application of these techniques is to develop simulations to determine the remaining life of the transformers. The work was supported by experimental trials conducted in Colombia. According to the results of these tests is recommended as a method of mechanical stress predictive detection systems and failure analysis for these teams, as t he development of preventive maintenance based on these unconventional methods, will soon a reality.