Insulation performance of safety-related cables for nuclear power plants under simulated severe accident conditions

To examine electrical insulation behavior of cables under severe accident environments, safety-related low voltage cables used as 'severe accident management equipment' were subjected to the test at 155degC, which simulated highest assumed temperature when proper accident management measures are taken. In addition, insulation resistance was measured for the cables during steam exposure in the test. As a result, all the cables passed the acceptance criteria of voltage withstand test prescribed in the JNES Guide. The minimum resistivity of the cables during the test at 155degC was around 10⁸ Ωm, confirming that the cables have a sufficient insulation performance. (author)