IEEE 422-2012 pdf download IEEE Guide for the Design of Cable Raceway Systems for Electric Generating Facilities
1. Overview
1.1 Scope
This document provides guidance for the design and installation of cable raceway systems for all types ofelectric generaing facilities.
1.2 Purpose
The guide provides recommendations, methods, and best engineering practices for the design of cableraceway systems including selection of equipment. materials, and the confipuration of raceway.
2. Normative references
The following referenced documents are indispensable for the application of this document (i.e. they mustbe understood and used, so each referenced document is cited in text and its relationship to this document isexplained). For dated references, only the edition cited applies. For undated references, the latest edition ofthe referenced document (including any amendments or corrigenda) applies.
3. Definitions and acronyms
For the purposes of this document, the following terms and definitions apply. The IEEE StandardsDictionary Online should be consulted for terms not defined in this clause.”
3.1 Definitions
cable shielding: A magnetic or nonmagnetic, conductive material applied over the insulated conductor orconductors to confine the electric field of the cable to the insulated conductor or conductors or to protectthe insulated conductors from external electrommagnetic or electrostatic interference.
cocoon (cable system enclosure): A cable wrap or enclosure used to protect cables from fire hazards andused to permit cable separation distances less than that normally required and which is typically made of afire resistant material.
conductor (strand) shield: The conductor shield consists of a layer of semi-conductive polymer or amalerial with a high dielectric constant that is extruded over the conductor. The conductor shield reducesthe dielectric stress at the inside surface of the insulation and prevents partial discharges by filling in thevoids and irregularities of the conductor surface and by providing a smooth, equi-potential surface at theinside surface of the insulation.
design life (of a cable): The time encompassing the service life of a cable and the anticipated marginbeyond during which a cable is expected to operate and perform its intended function.
design life (of a power generating station): The time during which satisfactory station performance canbe expected for a specific set of design operating conditions.
drop-out fitting: An attachment to a cable tray that maintains the proper cable minimum bend radius at thepoint that the cable exits from a tray. These fittings are available in configurations that can be attached tothe bottom, side, or end of a tray.
insulation shield: The insulation shield is a layer of semi-conductive polymer or a material with a highdielectric constant that is applied to the outer surface of the insulation in order to establish an equi-potential surface on the outside of the insulation. This ensures that there are no areas of concentratedelectric field due to sources outside of the cable, and minimizes the dielectric stress within the cableinsulation.
minimum pulling bend radius: The minimum allowable value of the radius of an arc that an insulatedconductor, insulated wire, or insulated cable can be bent under tension while the cable is being installed.