Aging, condition monitoring, and loss-of-coolant accident (LOCA) tests of Class 1E electrical cables

This report describes the results of aging, condition monitoring, and accident testing of crosslinked polyolefin (XLPO) cables. Three sets of cables were aged for up to 9 months under simultaneous thermal (≅100 degrees C) and radiation (≅0. 10 kGy/hr) conditions. A sequential accident consisting of high dose rate irradiation (≅6 kGy/hr) and high temperature steam followed the aging. The test results indicate that most properly installed XLPO cables should be able to survive an accident after 60 years for total aging doses up to 400 kGy and for moderate ambient temperatures on the order of 50--55 degrees C (potentially higher or lower, depending on material specific activation energies). Mechanical measurements (primarily elongation, modulus, and density) were more effective than electrical measurements monitoring age-related degradation