Category Archives: Cable Management

How to Choose the Proper Cabling Pathway?

Just as the old saying goes: it’s the little things that make the biggest impact. This is especially true when it comes to design a data center—there are so many factors to consider during the process, among which the proper cabling pathway construction only possesses a small part yet matters significantly. Data center designers are always aware of that multiple products must work together to ensure a successful pathway and cable management. This article will take a review of the commonly seen cabling pathway types.

What Is Cabling Pathway?

Cabling pathways allow the placement of data center trunk cables and cross-connect cables between racks and cabinets. Cabling pathway comes into two forms: overhead pathway and under floor pathway. Both of them are designed to accommodate all standards-compliant cabling and allow for necessary changes later. In other words, cabling pathway should support the weight of cables in the initial installation and also facilitate additional cables in the future. Which helps ensure robust pathways that respond well to cable work over the facility’s life cycle.

cabling pathway

Cabling Pathway types Overview

Cabling pathway types come in a dazzle array of styles, in this section, we’ll illustrate some of them that widely used in work areas, wiring closets and for horizontal and backbone cable runs.

Conduit

Conduits are pipes that cable is placed in and pulled through, and it can be metallic or nonmetallic, rigid or flexible. They run from the telecommunications room to the work area outlets in the floor, walls, or columns of a building. To ensure that enough conduit be installed, it is recommended that the conduit would better be only 40 percent full by your current cable needs, or 60 percent full to the maximum. Which leaves you space for future growth.

conduit

Cable Trays

Cable tray serves as an alternative cabling pathway component to conduit, which can be installed as distribution system to route and support your cables. Typically, cable tray is open and equipped with sides that allow cable to be laid within the tray’s entire length. It is ideal to use cable tray to manage a large number of horizontal cable runs, due to their greater accessibility when it comes to maintenance and troubleshooting, as well as its ability to accommodate change.

cable tray

Basket Tray

A basket tray serves as a cable tray that designed for light duty applications, which is lightweight and easy to install. Unlike ladder rack installation, to properly install a basket tray, certain level of experience is needed. Many of the accessories that accompany ladder racks also accompany basket trays, to ensure proper bend radius and a proper transition to the equipment rack.

basket cable tray

Underfloor Cable Tray

An underfloor cable tray is used primarily in data centers. It resembles much as overhead support pathway types. However, when using under floor cable tray systems, the air space may be a plenum air space, so all cable and patch cables would need to be plenum to ensure proper air flow.

underfloor cable tray

Ladder Racks

A ladder rack is made of tubular steel and comes in sizes from 6’’ to 36’’ wide. The installation of a ladder rack is simple and requires little trade experience. Ladder rack comes with many accessories such as 90-degree bends, waterfalls and cable retaining posts. These accessories allow the routing of cable without damage.

ladder rack

Raceways

Raceways are special types of conduits used for surface mounting horizontal cables. They are usually pieced together in a modular fashion with vendors providing connectors that do not exceed the minimum bend radius. Raceways are mounted on the outside of a wall in places where cable is not easily installed inside the wall. They are commonly used on walls made of brick or concrete where no telecommunications conduit has been installed.

cable raceway

Installation Considerations for Cabling Pathway

With the purpose of supporting the current needs as well as future growth, several essential factors should better be considered while designing and installing cable pathway.

  • Overhead and underfloor cabling pathway should be installed in a matrix type method, allowing cables to be routed from point to point anywhere in the data center.
  • When installing any types of cabling pathway, grounding and bonding are rather vital. Make sure that all racks, cabinets, and cabling support components are properly bonded and the system is grounded.
  • Always leave room for future growth. All cable tray and ladder rack should allow room to accommodate at least 50% growth after the initial install.
  • Be sure the heaviest cable in on the bottom of the tray or separated from the lighter cables, and separate the copper cables from the fiber cables if possible.

separate fiber and copper in cabling pathway

  • Avoid mounting any types of cabling pathway in locations that block access to other equipment inside and outside the racks.
  • Avoid routing pathways with copper cables near equipment, which may generate high levels of electrometric interference. Avoid areas around power cords, florescent lights, building electrical cables and fire prevention components.
Conclusion

The knowledge concerning different styles of cabling pathway lies the foundation of proper installation of data center pathway. Choosing proper cabling pathway type makes it easier to perform cable-related work and maintenance later. Make your decision on the basis of your unique working condition and environments, and do not forget to account for the factors mentioned below while perform cabling pathway installation.

Knowing Cable Ratings: Plenum and Riser Rated Cable

When doing data and voice cabling in premise environment, there is a common question that every installer may confront: Should I use plenum or riser rated cable? Plenum and riser here indicate flame ratings for cables which are defined by National Electric Code (NEC), with the purpose of preventing the spread of fire and smoke in commercial and residential buildings. Then, what is the difference between plenum and riser rated cable? This article will explain to you by making a comparison between them.

What are Plenum and Riser Cable?

The flame rating of cables differs according to various installation situations. Thus to decide which rating is appropriate for your installation environment is critical. So let’s just begin with the basic definition of the plenum and riser cable.

Plenum Cable: A plenum refers to any enclosed area that facilitates environmental air handling. Such as an air conditioning duct or an air routing drop ceiling. It can be any air space between walls, under floors, or dropped ceilings. Plenum cable is designed with a fire-retardant plastic jacket, that is laid in the plenum spaces of buildings. It is held to the most stringent testing of the cables rated by the NEC, rated for both flammability and smoke generation.

plenum rated cable

Riser Cable: Riser cables do what their name indicates—they rise between non-plenum vertical applications like floors of multi-story buildings. Riser cables may also penetrate either fire rated floors or walls. Described as backbone cables, riser cables serve as the main conduit of a distribution system for data, voice or video. The cables are only subjected to flame tests.

riser rated cable

Difference Between Plenum and Riser Cable in Application

In this part, we will illustrate the difference between plenum rated cable and riser rated cable from the perspective of their common application situations.

Plenum rated cable is usually made with strict standards required by a plenum space. It is installed to prevent contamination of the air. Requirements for plenum cables dictate the rate at which a flame spreads, as well as the maximum amount of smoke a burning cable may produce. This kind of cable can be applied to commercial and multi-family residential buildings. Plenum rated cables may substitute for riser and general purpose rated cables.

plenum and riser cable application

Riser rated cable is typically run between multiple floors of a building through open vertical shafts. Although these pathways do not handle environmental air, they can easily conduct a fire from one floor to the next if the cable is not properly rated. And the vertical spread of flame would pose a big threat to the safety. To minimize the spread of fire, riser rated cable is required for carrying a minimum of a riser rating. Riser cables may be used for different forms of data communications which also include CCTV video access. It is ideal as well for voice communications.

Plenum and Riser Cable in Cabling Design

When deploying cable for indoor applications, to plan and design beforehand is definitely critical yet beneficial. If the cables must be deployed in the plenum, it is important to remember that cables that will be deployed there must reach several standards on flammability, heat resistance, and amount of smoke cable generates when burning. Another essential part of installing cable within a building is riser cable deployment. Since riser cable should go through the whole building, it is rather vulnerable in case of fire. This is why riser cable has even more strict fireproof standards than the plenum one. The picture below illustrates the common design of the plenum and riser rated cable in the building.

plenum and riser cable design

Conclusion

Although cable rating is sometimes overlooked by system designers when selecting cables, it is rather vital to the whole installing environment. We have explained the difference between the plenum and riser cable from the perspective of the common application and cabling design, hope that would be informative enough.