In the production of electrical products, an important element is conducting exit and intermediate control operations to reduce risks. A promising approach to the diagnosis of electromagnetic devices is the analysis of their weber-ampere characteristics. Control of the magnetic properties of products allows identifying defects without the need for long-term operations of disassembly / assembly mechanisms. The introduction of sensors of magnetic magnitudes into the design of electromagnets is impractical in terms of cost and reliability. With the help of the "working" elements of electromagnets already available in the design, it is possible to measure the weber-ampere characteristics. The article solves the problem of analysis and identification of the relationship between the critical defect of armored-type electromagnets with the weber-ampere characteristic of the product and the development of a method for the technical diagnosis of a malfunction.