ARIES-ACT1 power plant has been designed and configured to allow for rapid removal of full power core sectors followed by disassembly in hot cells during maintenance operation. To achieve high availability and maintainablity of a fusion power plant, power core components of a sector, including inboard and outboard FW/blankets, upper and lower divertor, structural ring or high temperature shield were integrated into one replacement unit to minimize time comsuming handling inside plasma chamber. In this paper, the overall power core configuration and system integration, as well as the definitions of major power core components are described and main design features are highlighted.