UFC 3 -520-01
June 10, 2002
10-4.3
Commercial Building Groundin g and Bonding Requirements for
Telecommunications.
10-4.3.1 ANSI/TIA (Telecommunications Industry Association) /EIA (Electronics
Industries Association) -607 , Commercial Building Grounding and Bonding
Requirements for Telecommunications, provides the pertinent criteria for
communications systems grounding and bonding. The grounding and bonding
approach recommended in this standard is intended to coordinate with the cabling
topology specified in T IA/EIA -568B and installed in accordance with TIA/EIA -569A. The
purpose of this standard is to enable the planning, design, and installation of
telecommunications grounding systems within a building with or without prior knowledge
of the telecommunications systems that will subsequently be installed.
10-4.3.2 Apply ANSI/TIA/EIA -607 to all new facilities with many telecommunications
connections, extensive equipment rooms and telecommunications closets, or separate
entrance facilities. In this context, an entrance facility is an entrance to a facility for both
public and private network cables, including antenna.
10-4.3.3 Consider ANSI/TIA/EIA -607 as part of the maintenance, renovation, or retrofit
of telecommunications grounding systems in existing buildings. The wiring systems in
older buildings might not readily accept application of ANSI/TIA/EIA -607. In these
cases, perform an analysis to determine the cost of the application of ANSI/TIA/EIA -
607. Upgrades are permitted where the cost-benefit is considered acceptable.
10-4.3.4 The following summarizes the principal ANSI/TIA/EIA -607 design criteria:
10-4.3.4.1 Install a permanent telecommunications grounding and bonding system
independent of the telecommunications cabling. Use approved components and install
bonding connections in accessible locations.
10-4.3.4.2 Install a telecommunications bonding backbone (TBB) through every major
telecommunications pathway and directly bonded to a telecommunications grounding
busbar (TGB). A TBB provides direct bonding between different locations in a facility,
usually between equipment rooms and telecommunications closets. A TBB is usually
considered part of a grounding and bonding system, but is independent of other
equipment or cable. The TBB is intended to minimize ground potential variations
throughout the communications system. As a minimum, the TBB must consist of #6
AWG insulated copper bonding conductors and should be as large as #3/0 AWG
insulated copper bonding conductors for sensitive or very large systems. Each TBB
that reaches a location with a TGB mus t be bonded to the TGB. Visibly label each TBB
and TGB.
10-4.3.4.3 Bond each telecommunications main grounding busbar (TMGB) to the
electrical service ground. All TBBs terminate at this busbar. Generally, each TBB
should be a continuous conductor from the TMGB to the farthest TGB. Splice
intermediate TGBs to the TBB with a short bonding conductor.
10-4
Previous Page
