1 Reply Latest reply: Oct 27, 2015 5:31 PM by Darby RSS

Category 6A - F/UTP Testing

Scout

We are installing a shielded Cat 6a system. Do you have recommendations as to any testing of the integrity of the shield-to-ground at the Horizontal Cross-Connect?

  • Re: Category 6A - F/UTP Testing
    Scout

    The following are our “Best Practices” recommendations for ensuring shield integrity to ground for any of our shielded solutions. There are optional methodologies, of course, but we will always recommend best practices. The discussion below highlights grounding/bonding elements within a single telecommunications room. The TIA-607-B standard outlines the additional elements required for a larger Telecommunications Grounding System.

     

    1. Executive Summary:
    • First, Install and verify the Telecommunications Grounding System
    • Second, Install and verify all Leviton Shielded Permanent Links or Channels
    • Finally, Install individual #6 AWG Equipment Bonding Conductors (EBC) between each Shielded Patch Panel and the Rack or Cabinet bonding element
    • Note: Shielded Permanent Links or Channels are bonded to the Telecommunications Grounding System at one point (the Shielded Patch Panel). No grounding is done at the Work Area Connector (which is typically a Jack in a wallplate)

     

    1. Install Telecommunications Grounding System per TIA-607-B consisting of:
    • A Telecommunications Grounding Bussbar (TGB) within the Telecommunications Room/Horizontal Cross-connect (TR/HC)
      • This TGB to be bonded to Telecommunications Main Grounding Bussbar (TMGB). This bonding element is called the Telecommunications Bonding Backbone (TBB)
      • Connections of TGB to the TMGB should be made with an appropriate-size, UL listed, two-hole crimp style lug
    • TMGB to be bonded via Bonding Conductor for Telecommunications (BCT) to:
      • Structural Steel/Building Ground (preferred)
      • The electrical system ground point (if bond to structural steel cannot be obtained)
    • Use recommendations of the TIA-607-B standard for proper conductor gauge for all of the above TBB and BCT connections
    1. From TGB, a Telecommunications Equipment Bonding Conductor (TEBC) should be run for each row of racks or cabinets
    • This is typically a #6AWG bare or green-insulated stranded copper wire
    • If insulated, insulation must be appropriate for the space through which the TEBC runs (e.g. plenum (CMP) insulation if running through a plenum space)
    • Connections of TEBC to the TGB should be made with an appropriate-size, UL listed, two-hole crimp style lug
    1. There needs to be a specific equipment grounding element for each rack or cabinet
    • Equipment connections to each rack or cabinet from TEBC may utilize any one of three methods:
      • A Horizontal Rack Grounding Bussbar (Horizontal RGB) mounted to the rack or cabinet vertical equipment mounting rails
      • A Vertical Rack Grounding Bussbar (Vertical RGB) mounted to and running the full height of the rack or cabinet
      • A #6AWG Rack Bonding Conductor (RBC) running full height of the rack or cabinet
    • For each of the three rack/cabinet options above, connections are made to the TEBC via irreversible compression-type connections
    • The rack or cabinet itself is independently bonded to the TEBC via irreversible compression-type connection. This insures the structural metal of the rack or cabinet is bonded to the Telecommunications Grounding System in case that metal should become inadvertently energized.
    1. Grounding/bonding parts mentioned above are not from Leviton. Each of the elements above should be installed per manufacturer recommendations and tested per manufacturer recommendations to insure a low-impedance path to ground
    2. Leviton Shielded Permanent Link (work area jack to patch panel) or Channel (includes patch cords at both ends) should be installed per Leviton Shielded Connector Instruction Sheet
    • A Leviton Shielded Patch Panel must be used. Various standard and high-density options are available. Both flat and angled Shielded Patch Panels are available.
    • All patch cords used must be shielded patch cords
    • Leviton Shielded Patch Panels are engineered to provide a low impedance path from the Shielded Connector bodies (i.e. Shielded Jacks) to the Patch Panel sheet metal
    • A grounding stud is provided on the Standard-density Shielded Patch Panels
    • For High-density Shielded Patch Panels, the ground stud is accomplished via installation of a long rack-mount screw provided with the panel. Follow specific instructions that are included with these panels to ensure that adequate grounding is accomplished as part of panel installation.
    • If the Permanent Link or Channel architecture includes a Consolidation Point (CP):
      • Shield continuity must be maintained across the CP interconnect
      • Leviton recommends a Shielded Patch Panel in the CP for interconnect purposes. Standards do not allow Cross-connects in a CP.
      • Grounding for this architecture is still performed at the TR Shielded Patch Panel (i.e. no shield grounding performed at/within the CP)
      • Horizontal Cable section A will be a Shielded Cable running from the TR Shielded Patch Panel to the rear of jack in the CP Shielded Patch Panel
      • Horizontal Cable section B will be a Shielded Plug-to-Jack Cable Assembly running from the front of the CP Panel (shielded plug end into CP Shielded Jack in the Patch Panel and Shielded Jack end into workstation outlet)
      • Alternately, Horizontal cable section B may be a Plug-to-Open Cable Assembly (shielded plug end into CP Shielded Jack in the Patch Panel and open end cut to length and field terminated to a Shielded Jack for the workstation outlet)
      • Shielded Plug-to-Jack or Plug-to-Open Cable Assemblies are Make-to-Order products available from Leviton
    1. Field tester should be set for appropriate Category rating for the wiring system installed (i.e. Cat 5e, Cat 6, or Cat 6A) and for FTP cable type
    • Field tester Shield Continuity Testing should be Enabled
    • All Permanent Links or Channels should be characterized with the field tester, including shield integrity test. Repairs of any problem links should be undertaken and completed
    1. Finally, to ensure bond integrity of the Shielded Links or Channels to the Telecommunications Grounding System, an individual Equipment Bonding Conductor (EBC) should be installed from each shielded patch panel, to whatever element was provided for rack/cabinet bonding (i.e. Horizontal RGB, Vertical RGB, or RBC)
    • If RBC was chosen
    • Best practice
      • The thought behind a #6AWG EBC as best practice, is that this element is bonding the shields of all Links or Channels in the Shielded Patch Panel (i.e. 24 or 48 Links or Channels).
      • If most or all of these shields were to become inadvertently energized, one would want an EBC of sufficient size to reliably shunt this undesirable energy to ground.
    1. In summary:
    • Install and verify
    • Install and verify
    • Install individual #6 AWG Equipment Bonding Conductors
    • Shielded Permanent Links or Channels are bonded to the Telecommunications Grounding System at one point (the Shielded Patch Panel). No grounding is done at the Work Area Connector (which is typically a Jack in a wallplate)