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However, the approach to designing laboratory stands for training students and electrical per-sonnel on the specifics of using digital protections in most cases has remained the same, which does not allow for fully realizing their potential. The purpose of the work is to improve the qual-ity of the knowledge and practical skills received by students in the work with digital protection blocks. To achieve the goal, a specialized laboratory stand for testing digital security terminals has been developed. The stand consists of a mathematical model of the protected object, imple-mented in the form of a computer program and hardware, which allows real-time conversion of changes in model mode parameters into physical signals transmitted to the digital protection de-vice. The stand provides the terminal feedback with the model, which makes it possible to study the protection behavior in the characteristic operating modes of the protected element. The pro-tection of the "line-transformer" block using the Siprotec 4 7SJ6 Siemens terminal is considered. It is possible to calculate the protection operation parameters, configure the digital protection device, and also check the correct operation of the protections by automatically simulating nor-mal and emergency operation modes of the protected object. The software and hardware of the stand makes it easy to expand its capabilities by adding new models of power system objects and other digital protection devices. The equipment used in the developed stand does not require significant capital investments, which makes this approach accessible to higher educational insti-tutions.

The problems of experimental and theoretical research on the stressed and deformed state of steel structures under emergency actions are particularly relevant. Тhis paper proposes experimental and theoretical research methodology, which is used on the basis of an example of research on a full-length truss as part of the frame for an industrial buildings workshop. Components of the stressed-strained state of the structure are determined experimentally in the course of a simulated emergency situation. As emergency impacts, this paper considers the detachment of the air-cooling unit attached to a node of the lower chord of the truss. Experimental data is gathered through the joint use of the crate system, cable sensor and PC. The finite-element modelling of the structure behavior is performed based on the direct integration of differential equations of motion of the system subject to the local dynamic effects, and a comparison of data obtained with experiments results. As a result of using the test methodology we obtained the maximum weight of technological equipment fastened to the roof truss, while ensuring its normal operation in case of an emergency related to the failure to affix the equipment.