This document, based on national standards such as GB 50303 “Code for Acceptance of Construction Quality of Electrical Engineering in Building” and combined with engineering practice, systematically explains the full-process technical points for vertical cable trays – from material. This document, based on national standards such as GB 50303 “Code for Acceptance of Construction Quality of Electrical Engineering in Building” and combined with engineering practice, systematically explains the full-process technical points for vertical cable trays – from material. maintain spacing or to keep cables in place when the tray is ect the minimum bend ra-dius for cables as they exit the bottom of the cable tray. A rung spacing of 6 to 9 inches (150 to 230 mm) is preferable when the cable tray cont d for instrumentation and control applications that require. us-trations without notice. All illustrations, descriptions and technical information included in this document are provided as indications and can cable trays are equivalent. The mechanical and electrical characteristics, tests, certifications, overall quality management, recommendations mentioned in this technical guide only apply to our own cable management ranges and cannot under any circumstances be transpos regulations which. As a key support system for cable laying in building electrical engineering, the installation quality of vertical cable trays directly affects the safe operation of power, communication, and other circuits. This document, based on national standards such as GB 50303 “Code for Acceptance of. Cable tray (or cable ladder) systems are a popular alternative to electrical conduit systems, as they have an outstanding record for dependable service, design flexibility and cost savings in commercial and industrial applications. 6) and the universal bracket (p.