Non-destructive diagnostic facilities for cable systems

Polymeric materials like polyethylene and silicone rubber used in cables, joints and terminations show an electrical aging behavior. Considering the consequences of dielectric aging, effective diagnostic facilities are currently required, which have to be primarily nondestructive and which should detect as many faults as possible. Based on previous experiences it can be expected, that ultrasonic measurements and nuclear magnetic resonance (NMR) investigations fulfill these requirements. In addition the possible use of these facilities for quality management is presently being investigated. The increasing miniaturization, combined with the possible application of mobile diagnostic devices, is taken into account. First results show the feasible use of these facilities for detecting inhomogeneities like impurities and electrical trees in the insulation material and for identifying variations of the cross-link density.