Industrial Automatic Control Systems and Controllers Annotation << Back Modernization of the Automatic Control System for a Pumping Unit Based on the Domestic Hardware and Software Suite "TEKON" Vlasova O.V., Shevlyagina S.A. The article presents the practical implementation of import substitution in the fi eld of industrial automation, using the modernization of a pumping unit control system as an example. A transition from the foreign Siemens platform to the domestic hardware and software suite "TEKON" is proposed. The authors examine architectural solutions, the structure of application software implemented in the ST language in accordance with IEC 61131-3, emergency shutdown system algorithms, and integration with the SCADA system via the Modbus TCP protocol. Keywords: DCS, import substitution, TEKON hardware and software suite, programmable logic controller (PLC), SCADA, Modbus TCP, emergency shutdown system, industrial safety, modernization. DOI: 10.25791/asu.8.2026.1678 Pp. 25-34.