A localized trace element analysis of water trees in XLPE cable insulation by micro-PIXE and EDX

PIXE (proton-induced X-ray emission) with a focused proton beam of 30-or 220- mu m diameter and EDX (energy dispersive X-ray analysis) of water-trees in XLPE HV (cross-linked polyethylene high-voltage) cable insulation. The merits of these two methods are compared and discussed. It is shown that water-trees are more contaminated than the surrounding insulation. On a localized basis the impurity content of the untreed insulation varies considerably within a few square millimeters.<
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