We applied eddy current transducer (ECT) to examine the electric steel parameters. The research topic is considered relevant due to the need for evaluation and forecasting of safe operating life of electric steel products. A scheme that uses a computer as a generator and receiver of signals from windings is proposed. Having the designed transducer as a basis, a hardware-software complex was built to perform experimental studies of steel at the interface boundary. The article provides the key technical information about the eddy current transformer used and describes the methodology of measurements that makes it possible to control steel to dielectric transition. Test results are reported for a specimen with continuous and discrete measurements taken at different frequencies. The curve of introduced voltage amplitude as a function of sensor location was constructed to study in details the introduced voltage drop at the ferromagnetic-dielectric interface. Presentation of induced voltage changes in the form of mathematical dependences enables to elicit the ways of interaction between electromagnetic field of eddy-current converter and residual magnetic field of steel.