Results from two years of validation testing in the Permian region indicate that replacement of direct current (DC) withstand testing procedures with very low frequency (VLF) withstand and tan-delta diagnostic methods promises to provide more accurate and more informative testing with less detrimental effect to cable integrity. The combination of VLF withstand and VLF tan-delta tests, which can both be conducted using the same equipment from HV TECHNOLOGIES, Inc., can provide a more accurate and less intrusive withstand test and a quantitative estimate of cable integrity and defect pattern. Four properties computed from tan-delta measurements, including tan-delta mean, tip-up, tan-delta deviation stability, and tan-delta skirt stability, are examined and upper and lower bounds for acceptance testing are developed for cable testing in the artificial lift industry. For tan-delta mean and tip-up, Korean Electric Power Corporation (KEPCO) degradation classifications should be adopted to enable end-users to make informed risk assessments about cable reuse. In light of a lack of information on the practical significance of stability values, KEPCO criteria for stability should be adopted to identify highly degraded cables without overly pessimistic assessment of cable condition and subsequent needless rejection of good cables. It is feasible to further refine these testing criteria using multi-feature models based on cable run-life and to diagnose cable defect patterns using multi-feature models. Proven methods used in the power distribution industry should be adopted to create artificial lift specific testing criteria and cable run-life models using industry run-life data.

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