Migration of the old control systems based on S5 series controllers to the new control system based on S7 series controllers is an investment that primarily ensures: the optimization of the production process, the reduction of the probability of failure, the lack of problem with a difficult to find and expensive spare parts. We already have many successful migrations in our portfolio. These apply to both small and large systems. Control-Service engineers developed a concept that allows a company to reduce or even to eliminate the impact of migration on production plans. We treat each control system individually and we develop the best and the optimal action plan.
The steel plant for which the task was performed did not have systematic change procedures in the PLC. With the constant replacement of the automation staff, it led to the overflow of the controller’s processor memory with unnecessary technological blocks. The system additionally exchanged data with the proprietary MES system in a way not fully identified by the engineers working at the plant. Such a state caused frequent downtime caused by unnecessary blockages and temporary shortages of production parameters which elimination was crucial for the customer due to the requirement of their constant control.
To cope with the task, our engineers had to get to know the entire process, which was possible only via observation and consultations with technologists and operators at the plant. The additional difficulty was caused by the lack of up-to-date electrical documentation. It was necessary to identify each signal entering and exiting the PLC.
After the migration, the customer received full, up-to-date electrical documentation. We have provided all source codes for PLC programs. The PLC program structure has been greatly simplified by eliminating unnecessary program interlocks. The program has become more transparent for maintenance engineers and more reliable. Communication with the MES system has not only been preserved but also improved thanks to its in-depth analysis.