Condition Monitoring of Nuclear Cable using the Indenter Modulus

Abstract

In general, the degradation of low voltage power, control and instrumentation cables is due to the oxidative embrittlement of the insulation and jacket materials. Experience has shown that service cable failure has occurred due to the embrittlement and cracking of the insulation followed by a loss of dielectric strength and high leakage currents. Consequently, the end of life criteria for insulation has been bed on absolute elongation at break values. However, samples required to measure elongation values are relatively large and require the removal of cable sections from the plant. The Indenter Polymer Aging Monitor was developed for use as an in-situ, non-destructive diagnostic tool for tracking the degradation of nuclear cables and seals. The operation of the Indenter is discussed along with laboratory and field results.