Maintenance and automation. Using a common system As regards maintenance tasks, the status-relevant data are collected and preprocessed at the Controls level. Depending on the respective specified categories and process steps, the corresponding requirements can be forwarded to the higher levels in order to plant and coordinate the execution of the initiated measures with the aid of the functions found there. Monitoring, control, coordination of in-service automation processes and the functional sequences for the maintenance planning and execution are made visible over interfaces. Implementing all of this in one system offers many advantages: Uniform visualization for all components and devices Plant components can be used directly as information source Combination of automation and asset management functions Engineering data for automation can also be used for maintenance Simplification thanks to uniform engineering and HMI tools