The choice of equipment of technological enterprises, especially when the characteristics of the equipment are close in values, remains an urgent task. In our work, to evaluate the effectiveness of programmable logic controllers (PLCs), a comprehensive criterion for evaluating efficiency is proposed, as well as a method for calculating it using numerical methods. To calculate the complex efficiency criterion, the values of the significant characteristics of the controllers selected by us are converted into points on a linear scale. To refine the calculation results, we applied one of the Newton-Cotes numerical methods, namely the trapezoid method. Next, we used the method of cubic interpolation of the obtained curves to increase the accuracy of calculations. The proposed method is simple and does not require a lot of calculations. At the same time, its application makes it possible to calculate complex PLC efficiency criteria based on characteristics relevant to a particular control process.

Keywords: programmable logic controller, characteristics, numerical methods, trapezoid method, cubic interpolation method, aggregation of characteristics, ABAK PLC, Siemens PLC, OWEN PLC

In this paper we proposed a method for quantifying the total efficiency of programmable logic controllers from various manufacturers. The correct assessment makes it possible to select a programmable logic controller (PLC) as part of the implementation of the import substitution policy with a domestic product of devices from competing companies that have left the Russian market. The solution of the problem is carried out by the introduction of a linear rating scale for the selected characteristics of the PLC. Quantitative assessment of the qualitative characteristics of PLCs made it possible to obtain the value of the total efficiency for the PLCs considered in the work. Total efficiency is understood as a comprehensive assessment of the effectiveness of a programmable logic controller according to the selected characteristics. In this case, the characteristics may be of a different nature. We evaluated programmable logic controllers of four manufacturers: Siemens, Yokogawa, OWEN, ABAK. Seven characteristics of the PLC were selected for evaluation: mean time between failures, number of interfaces and plug-ins, power consumption, temperature range, number of protocols used, and response speed. The possibility of implementing the import substitution policy is considered. The assessment of the total efficiency confirmed the competitiveness of domestic PLCs in relation to foreign ones. The development of the presented evaluation method will make it possible to analyze the effectiveness of complex, large control systems made up of different types of equipment. The presented method can be used over time to obtain up-to-date information about the total efficiency.

Keywords: programmable logic controller, evaluation parameters, qualimetry, total efficiency, import substitution