This means routing must be through dedicated, fire-resisting cable support systems – no sharing trays. This guidance covers the routing of secondary supply cables from a life safety generator to the ATS (Automatic Transfer Switch), and the final equipment with reference to: The goal: clarify requirements for the diverse cable routing and maintain circuit integrity under fire conditions for systems. The primary rulebook used in the safe use of cable trays is NEC Article 392. This is a description of how to select, install, and support these metal or plastic frames, on which electrical wires are installed. You should consider it as a series of instructions that make the buildings resistant to. Cable tray systems are structural components used to support insulated conductors and control, instrumentation, and communication cables. Main. Coordinate with Building Structure: Cable tray routing should align with architectural design, avoiding unnecessary crossings, detours, or overlaps with other pipelines. Shortest and Straightest Path: To reduce cable loss and simplify maintenance, cable routes should be as short and straight as. Separation isn't just an EMI precaution — it protects signaling, reduces rework, and ensures pathways meet inspection expectations across risers, plenums, and shared trays. Here is the summary of the main points found in NEC Article.