The importance of control for objects with timedelay links is very high; the rising number of control theory publications proves this case. However, the theoretical results are often very far from practical results. We can assume that the most common reason for this is fundamental simplification of the model in the system identification process. This paper presents the example of a plant from [1] to test the model’s validity and its feasibility in the case of the control design with negative feedback loop. The paper resolves the stated problem by means of mathematical modeling (simulation) in program package VisSim