Issue link: https://www.e-digitaleditions.com/i/1414667
October/November/December 2021 I 61 Underwriters Laboratories (UL) 2043 certification states that PoE devices are "suitable for installation in air handling spaces." All connections to PoE devices are low voltage, including LED lights and sensors (12-48 VDC) and the PoE input power (55 VDC). The NEC Class 2 definition does not require conduit or enclosures of any kind at these voltage and power levels. This gives the installation contractor a lot of flexibility in terms of how and where to install various components of the system to achieve maximum efficiency (Figures 1,2, and 3). Inherently, PoE is safer than traditional power delivery mechanisms. The safety features are built in. Network switches will not grant power to a cable without the necessary verification that there is PoE on the other end. FIGURE 3: (Left) The PoE infrastructure at Codisa consists of cables running in the overhead tray connecting lighting, sensors, and any other PoE-enabled end devices. (Right) Close-up of the Cat 6A field term plug that connects into the equipment shown at left. The plug is backward compatible with Cat 6 and Cat 5e. Photo courtesy of Panduit. FIGURE 1: PoE-tunable white lighting system installed in a Codisa hallway. Photo courtesy of BC Network. FIGURE 2: PoE-powered lighting at Codisa with customizable lighting capabilities. Photo courtesy of BC Network. Of course, PoE installers must adhere to national electrical requirements and the rules of certain local jurisdictions. In Chicago, for instance, all cables in a plenum space, including PoE, must be in conduit. In New York City, slightly higher requirements apply to emergency lighting, a use case well suited for PoE, making it a frequent install for installation teams. Each of the nodes should have a UL924 certification option to meet most local emergency lighting requirements. These UL ratings are more universally accepted today than ISO/IEC standards in relation to PoE.