There are many diagnostic techniques commercially available for medium voltage (MV) cable systems. These techniques have varying sensitivities and modes of application. However, since there is no North American standard for test-based condition assessment of MV cable systems, circuit owners are faced with what can be a confusing array of choices and selection of the most appropriate techniques for a particular application can be challenging. Several independent bodies such as CEATI, NEETRAC, and CIGRE have published documents describing various techniques. This report forms an extension of these publications, emphasizing areas where information gaps exist.
The methodology, theory, sensitivities, and applicable guidelines, and standards for various field assessment techniques are presented. Tests are also evaluated in terms of field application experience, required level of expertise regarding the particular topics, and knowledge gaps and constraints.
Through this report, the circuit owner can gain knowledge and awareness of relevant public sources that address test-based condition assessment of MV distribution cables. It provides a base level of knowledge that can allow for independent decision-making with respect to developing test programs that meet specific condition assessment objectives. Furthermore, it provides the information necessary to differentiate and critically assess equipment vendors and service providers when presented with a potentially confusing array of available commercial and proprietary options.
Medium voltage cable, Diagnostic testing, Laboratory testing, VLF 0.1 Hz Dielectric Loss, VLF tangent delta, Frequency domain dielectric spectroscopy, Time, Domain dielectric spectroscopy, Polarization and depolarization current, DC insulation resistance, Neutral resistance, Conductor resistance, Partial discharge (off-line or on-line), Frequency domain reflectometry, Time domainre flectometry, Insulation withstand, Jacket withstand, Infrared thermography, Indenter testing.