IEEE 400-2012 pdf download IEEE Guide for Field Testing and Evaluation of the Insulation of Shielded Power Cable Systems Rated 5 kV and Above
3. Definitions，acronyms, and abbreviations
3.1 Definitions
For the purposes of this document, the following terms and definitions apply. The IEEE StandardsDictionary: Glossary of Terms and Definitions’ should be referenced for terms not defined in this clause.
breakdown: Disruptive discharge through or along the insulation.
cable system: One or more lengths of shielded power cable joined together, 5 kV and above, includingcable accessories (joints and terminations).
dielectric response: A collection of parameters, such as dissipation factor, DC leakage current.polarization current, etc, which characterize the overall behavior of the insulation of a power cable systemunder an applied voltage of various types and frequencies at various temperatures.NOTE-The definition of dielectric response in this document must not be confused with that of the same term usedfor semiconducting materials.
electrical tree: Tree-like growths, consisting of non-solid or carbonized micro-channels, that can occur atstress cnhancements such as protrusions, contaminants, voids or water tree/dry insulation interfacessubjected to electrical stress for extended time periods. At the site of an clectrical tree the insulation isdamaged irreversibly. lf the voltage stress on the clectrical tree is above the inception voltage, partialdischarge will be present, the tree will grow, and a failure can only be a matter of time.
ethylene propylene rubber (EPR): A type of polymer used as clectrical insulation in cables andaccessorics. There are several different formulations of EPR and they have different characteristics. Forpurposes of this guide, the term also encompasses ethylene propylene diene monomer rubber (EPDM).
extruded dielectrics: Insulation such as polyethylene (PE), crosslinked polyethylene (XLPE), trecretardant crosslinked polyethylene (TRXLPE), ethylene propylene rubber (EPR), etc. applied using anextrusion process.
hybrid cable system: A cable system consisting of cables with very different dielectric or constructioncharacteristics; for example extruded diclectric insulation cable and laminated insulation cable or cableswith filled and unfilled insulations.
insulation weak spot: A part of the cable insulaion system where, due to onc or more factors such asmechanical, chemical, or thermal stresses, the insulation medium breaks down before the rest of the systemunder certain applied voltage. An insulation weak spot that leads to a breakdown at operating voltage issometimes called a gross defect.
laminated dielectrics: Insulation formed in layers typically from fluid-impregnated tapes of eithercellulose paper or polypropylene or a combination of the two. Examples include paper insulated leadcovered (PIL.C) cable designs, Mass Impregnated Non Draining (MIND) cable designs, high pressure pipetype cable designs, and self contained cable systems.
partial discharge (PD): Localized electrical discharge that only partially bridges the insulation betweenconductors.
partial discharge (PD) pulse: A high-frequency current or voltage pulse that results from a partialdischarge. In a shielded power cable, the pulse propagates away from the PD source in both directionsalong the cable.
polyethylene (PE): A polymer used as electrical insulation in cables.
shielded cable: A cable in which an insulated conductor is enclosed in a conducting envelope.