The next task was to recreate the PLC portion of the plant into the process screens of the System 800xA HMI. ABB has efficient tools for automatic conversion of process screens from Siemens WinCC to System 800xA that typically convert up to 80-90% of the objects. However, recreating the old process screens would not fully benefit the operators, even if available in the System 800xA HMI.
Instead the information from the PLCs was directly integrated into the existing process screens of the System 800xA HMI at the Ålidhem district heating plant. With this approach, they could optimize the presentation in the process screens and what originally needed 100 process screens in Siemens WinCC now only needed a total of 20 new process screens in the System 800xA HMI.
Different hardware, same look, one HMI
This faceplate for a Siemens PLC controlled pump serves as a good example of the final result. Having the same look as any pump faceplate in System 800xA, it shows the same information in the same manner regardless of being controlled by a Siemens PLC or a ABB controller, and that is the point: for the operator, it doesn’t matter which controller or PLC is connected to the asset, everything works in the same way in a seamless integrated environment.
While being able to retain the plant investment in existing hardware such as cabling and controllers, Umeå Energi now has an improved and simplified single operator interface to their complete plant, resulting in an improved monitoring and process control.
In the commissioning stage both ABB and Umeå Energi benefitted from being able to use the old WinCC and System 800xA HMI side by side, giving the project team and operators the opportunity to fine tune the integration and complete the engineering for as long as needed to create the best possible result.