Circuit by circuit power cable separation in nuclear power plants

Many nuclear power plants, designed prior to 1975 were engineered to achieve the independence of the circuits and equipment comprised of or associated with Class 1E systems; this was achieved by the means of circuit by circuit physical separation and electrical isolation rather than by unitized raceways on a train basis to a greater degree than at post 1975 designed plants. Because circuit by circuit separation results in cables from different power trains being routed in the same cable trays, a careful analysis is required to ensure that redundant Class 1E circuits are not routed in the same raceways. This paper presents the analysis done for the power cables at the Consolidated Edison Company´s Indian Point 2 nuclear power plant and identifies the steps required to maintain this power cable configuration