Migration from S5 to S7-1500 controllers and development of new electrical documentation
Migration of control systems from Siemens S5 controllers to modern Siemens S7-1500 controllers is an investment that improves system reliability, optimizes production processes, and reduces the risk of failures associated with aging hardware. It also eliminates issues related to the increasingly limited availability of spare parts.
Our portfolio includes numerous successfully completed control system migrations, ranging from small installations to complex industrial systems. Control-Service engineers have developed a migration approach that minimizes—and in many cases completely eliminates—the impact of modernization work on production schedules. We treat every control system individually, selecting the most effective migration strategy based on the specific process requirements and operational needs of the facility.
Goals
- Optimization of production processes
- Elimination of downtime caused by software malfunctions
- Improved reliability of the control system
- Updated and organized electrical documentation
Challenges
- Lack of complete and up-to-date documentation
- Integration of production data with a custom MES system
- Identification and verification of PLC input and output signals
- Simplification of the controller program structure without disrupting production operations
Solutions
- Implementation of Siemens S7-1500 controllers
- Close cooperation with process engineers, operators, and maintenance teams
- Development of a new control algorithm
- Analysis of the data exchange architecture between the PLC and the MES system
- Preparation of complete new electrical documentation
- Delivery of full PLC source code documentation
Benefits
- Elimination of downtime caused by software errors
- Simplified controller program structure
- Improved code readability for maintenance engineers
- Continuous monitoring and measurement of production process parameters
- Enhanced communication with the MES system
- Up-to-date electrical documentation supporting future maintenance and system development
Situation before modernization
The steel plant for which we carried out this project did not have standardized procedures for managing modifications to its PLC control systems. Combined with frequent turnover among automation engineers, this resulted in processor memory being overloaded with unnecessary process interlocks and technological constraints.
The system also exchanged data with a custom MES platform through mechanisms that were not fully identified or documented by the plant’s engineering team. This situation led to frequent downtime caused by excessive interlocks and temporary loss of production data. Eliminating these issues was critical for the client, as continuous process monitoring and control were essential to plant operations.
Project implementation
To successfully carry out the S5 to S7-1500 migration, our engineers first gained a thorough understanding of the entire production process. This was achieved through on-site observation of plant operations and close collaboration with process engineers, operators, and maintenance personnel.
An additional challenge was the lack of up-to-date electrical documentation. As a result, every PLC input and output signal had to be individually identified and verified. Based on this work, we developed new electrical documentation and reorganized the structure of the control system.
As part of the project, we developed a new control algorithm, simplified the PLC program, and analyzed the data exchange architecture with the MES system. This approach ensured continuous monitoring of process parameters while improving communication between the control and production management systems.
Migration results
Upon completion of the migration, the client received complete and up-to-date electrical documentation, along with the full source code of the PLC programs. The controller software structure was significantly simplified, and unnecessary process interlocks were removed.
The controller program became easier for maintenance engineers to understand, diagnose, and maintain, resulting in improved overall system reliability. Communication with the MES system was preserved and further enhanced through detailed analysis and optimization of the data exchange mechanisms.
Summary
The Siemens S5 to S7-1500 migration significantly improved the reliability of the control system, reduced the risk of downtime, and ensured that the electrical documentation was fully updated and organized. Through a tailored migration strategy, close cooperation with the client’s team, and a detailed analysis of the integration with the MES system, we delivered a modern, transparent, and robust control system fully aligned with the requirements of the metallurgical facility.
