An existing substation is subject of a retrofit (partial / the complete substation) of the secondary (and the primary) equipment. The substation is already captured in the CIM model of the control center; (the single line diagram is adapted to the new primary equipment). Based on that, the substation is designed using IEC 61850. The operational information exchange between the substation and the control center needs to be engineered. The protection engineering is done on a centralized engineering workplace by the protection engineer.