While ABB thinks its cable degradation can be negligible in the right temperature band, independent assessors ERA Technology claims polymeric cable insulation (XLPE) is susceptible to degradation when used in wet environments. This degradation mechanism results in the formation of water trees.
These conclusions are the result of a new test system using shorter cable lengths and less laboratory space. Previous tests required large amounts of cable aged over two years. The full results of this research are available from ERA Technology – at a price.