The latest update to the standard addresses large single-story buildings, harmonizes terminology, and includes an informative annex covering towers and antennas.
By Patrick McLaughlin
In spring 2014 the Telecommunications Industry Association (TIA; www.tiaonline.org) issued a call for interest for the third revision of the TIA-607 standard document covering grounding (earthing) and bonding of telecommunications facilities. Generally the TIA issues such a call soon after it has committed to develop or revise a standard. The 607 standard series is administered by Subcommittee TR-42.16 Premises Telecommunications Bonding and Grounding. By the time TR-42.16 met the week of October 12, 2015, the group had made progress on the revision to the point at which it had a single comment to resolve, and it was expected that the completed document would be submitted for publication either during the week of October 12 or shortly thereafter.
When issuing the call for interest, the TIA explained that one objective of the “C” revision would be to address the fact that “today’s large telecommunications facilities are built on one level.” The bonding backbone system specified in the then-current, TIA-607-B standard, exhibits a vertical layout. “This will be updated in the TIA-607-C release, which will introduce a horizontal bonding backbone topology to address this type of building. The new revision will also specify requirements for a generic telecommunications bonding and grounding infrastructure and its interconnection to electrical systems and telecommunications systems.”
Another objective was to harmonize international and U.S. domestic grounding and bonding specifications, thereby reducing confusion within the market. In its 2014 call for interest the TIA said, “Domestic and international codes and standards groups have been working on correcting terminology regarding bonding and grounding for approximately 10 years. Where there is confusion with bonding and grounding, electronic systems can fail. The improper grounding of separately derived systems can lead to equipment malfunction and other data issues. Once this new revision is completed, it may also be used as a guide for the renovation of existing systems.”
The nearly complete draft of the TIA-607-C standard includes nine sections: Scope; Normative References; Definitions, Acronyms and Abbreviations, Units of Measure; Regulatory; Overview of Telecommunications Bonding and Grounding Systems; Telecommunications Bonding Components; Design Requirements; External Grounding; Performance and Test Requirements.
Within the section Overview of Telecommunications Bonding and Grounding Systems, the standard includes an illustration of a grounding and bonding system in a large, single-level building. That illustration depicts the horizontal bonding backbone topology specified for such a building. That section of the standard also includes an illustration of a large multi-story building and a small building, each including the building’s bonding topology.
The Definitions, Acronyms and Abbreviations, Units of Measure section comprises multiple pages and does not literally go from A to Z, but does go from A (“access floor”) to W (“work area cord”). As the TIA stated in 2014, an objective of this particular section is to correct any terminology that may have been causing marketplace confusion and by doing so, to decrease the likelihood of electronic system failure resulting from such confusion or misunderstanding.
After those nine sections, the document contains six annexes, lettered A through F. The annexes are not part of the standard; they are informative rather than normative. In layman’s terms, that means there is no requirement to comply with the informative annexes in order to be in compliance with the standard.
One of the annexes lists a cross-reference of terms used in the TIA-607-C standard and terms used in other standards, including previous TIA-607 standards. This cross reference also serves as a means by which harmony is achieved with international standards-again for the purpose of clarifying what may have been confusing for industry professionals over the past several years.
The lengthiest of the six annexes discusses grounding and bonding of towers and antennas. Among the specific tower types and locations it covers are: guyed metallic towers, self-supporting metallic towers, wooden structures, shelters and outdoor cabinets, rooftop sites. It also includes information on grounding fences, generators, and satellite dishes. Because it is informative rather than normative, the annex contains “should” rather than “shall” statements. And although it is not technically part of the standard, this annex is likely to be a valuable reference for professionals who work with the various towers that physically support antenna-based wireless communication systems as well as some wired systems.
The TIA’s entire family of standards-including those developed by TR-42 for telecommunications systems-is available for purchase through IHS. IHS has established a “TIA Standards Store” web page where they can be purchased; the TIA-607-C standard is likely to be available for purchase in that store before long. Individuals can reach the TIA Standards Store directly at global.ihs.com/?rid=TIA.
Patrick McLaughlin is our chief editor.