IEEE 400.2-2004

This guide describes very low frequency (VLF) withstand and diagnostic tests and the measurements that are performed in the field on service-aged shielded medium voltage cables with extruded and laminated dielectric insulation. VLF test methods utilize ac signals at frequencies less than 1 Hz. The most commonly used, commercially available, VLF test frequency is 0.1 Hz. Whenever possible, cable systems are treated in a similar manner to individual cables. Charts are included as an aid in identifying the effectiveness of the VLF test for various cable insulation problems. The introduction of cables with extruded dielectric insulation has imposed new standards and restrictions on field testing of shielded medium voltage systems. DC testing of shielded medium voltage cable systems frequently causes service-aged cables with solid dielectric insulation to fail after they are returned to service. This guide is intended to provide troubleshooting and testing personnel with information to test shielded medium voltage cable systems using very low frequency techniques. New IEEE Standard - Superseded. This guide describes very low frequency (VLF) withstand and diagnostic tests and the measurements that are performed in the field on shielded power cable systems. Whenever possible, cable systems are treated in a similar manner to individual cables. Tables are included as an aid to identifying the effectiveness of the VLF test for various cable system insulation problems.