Recommended test methods for underground power cables containing superabsorbent materials

This paper recommends new test media and methods for underground power cables with superabsorbent water swelling materials (SAP). The tests should reflect actual service conditions in the field. The type of water chosen for swelling tests should have ionic content to reflect the composition of actual soil water. The cable tests should also reflect actual conditions. The tests should measure the performance of the cable under simulated thermo-mechanical loading conditions, under water pressure at the operating voltage. The testing should highlight the water-blocking performance of the SAP in its functional state, that is, in the form of a hydrated gel. Such requirements are already a part of International Electrotechnical Commission (IEC) test methods and are also a requirement for certain Insulated Cable Engineers Association (ICEA) test methods thereby allowing harmonization of the global requirements for water-blocked cables.