Work continues on standard for industrial cabling systems

TIA-1005, which still has hurdles to jump, could be an example of specification harmonization among several standards-setting groups.

When the Telecommunications Industry Association’s (TIA; www.tiaonline.org) TIA/EIA-1005 standard is finalized, which could be by this time next year, it will be the culmination of nearly a decade’s worth of work to specify cabling systems in industrial environments. The project started in 1998, and in the years that have followed, the group that is constructing the standard has made a great many strides in setting specifications. Still, the TIA’s consensus-based standards-creation process presents a few more steps to take before the standard can be called official.

“Technically, anything can change, but certain parts of the standard are pretty well set,” explains Robert Lounsbury, principal engineer with Rockwell Automation (www.rockwellautomation.com) and chair of the TIA’s TR-42.9 Industrial Telecommunications Infrastructure Subcommittee. “Cabling performance requirements are solidifying and connector specifications are pretty well along. Research is being conducted on bulkhead connectors and their performance requirements.”

Tasks at hand

With specific parts of the standard in various stages of completion, the process of getting it through the approval process marches on. As of the time of this writing, TIA-1005 is in a Standards Proposal (SP) process, also called a “pink ballot.” According to the TIA, this step is necessary for any document that will be an American National Standard, under the auspices of the American National Standards Institute (ANSI; www.ansi.org). TIA, on its Web site, further explains that during the SP balloting period, “any interested party may cast his/her vote. A party can respond in three ways: affirmative, affirmative with comment, or negative with comment. Every attempt is made to resolve comments received at this phase of the balloting.” Hence, Lounsbury’s statement that technically speaking, any part of the standard still can change.

Meanwhile, within TR-42.9, work continues in earnest. In fact, some efforts toward the forthcoming TIA-1005 standard are coming from outside TR-42.9.

The TR-42.3 Commercial Building Telecommunications Pathways and Spaces Subcommittee formed a task group on industrial pathways and spaces; that group has drafted a document that may ultimately be an addendum to TIA-1005 or, depending on the timeframes within which both documents are finalized, the TR-42.3 contribution may become part of the 1005 standard. Either way, the TR-42.3 group’s efforts to establish pathway specifications for industrial environments has allowed the TR-42.9 group to focus on cable and connectivity issues.

A task group within TR-42.9 is focusing specifically on fiber-optic cabling systems for industrial environments. Lounsbury states that fiber-optic systems have always been part of the committee’s plan. “Fiber has been identified as an area where there was not enough guidance,” in a draft set of specifications, he explains. “The task group was developed to determine best practices for fiber connectivity. The group has done a very good job and is now doing some final, cleanup-type work.”

All in all, the cabling and pathway specifications for industrial systems have shaped up significantly, and Lounsbury sees the light at the end of the standards-process tunnel. Lounsbury says his goal as TR-42.9 chair is to have that committee’s work done within the next year.

Of MICE and mitigation

Another of his goals is for certain significant parts of the TIA-1005 standard to be harmonized with other standards, put forth by other organizations, covering networking technologies in industrial applications. No fewer than six standards organizations (including the TIA) either have completed or are in the process of developing specifications that, in some way, address the topic of “industrial Ethernet.” For example, the International Organization for Standardization (ISO; www.iso.org), in conjunction with the International Electrotechnical Commission (IEC; www.iec.org), recently published the ISO/IEC-24702 Cabling Systems for Industrial Premises Standard. And in much the same way that the ISO/IEC-11801 standard set is generally considered the “international equivalent” of the TIA/EIA-568 series of specifications, ISO/IEC’s 24702 standard can be seen as a parallel to the TIA/EIA-1005 standard.

But other groups are addressing industrial networking at levels other than the physical layer, and Lounsbury states that it is not only possible but probable and appropriate that certain key elements of those standards (such as drawings) exist in harmony rather than conflict with the ISO and TIA standards.

He points to the MICE table (above) as a prime example. “It is absolutely mandatory for the MICE table to be harmonized,” he emphasizes. The MICE table is a means by which users can categorize their environments according to four considerations: mechanical (M), ingress (I), climatic (C), and electromagnetic compatibility (E). A user can consult the table to determine their environment’s class; the table rates each of the four conditions on a scale from 1 to 3. A tutorial that accompanies the table will vary from group to group, but the table itself should be the same in any document in which it appears.

A recently published set of specifications from the Open DeviceNet Vendors Association (ODVA; www.odva.org) entitled “EtherNet/IP Media Planning and Installation Manual” is a 124-page manual that includes the full MICE table and gives readers guidance how to build systems to meet their plants’ requirements.

Just as important as maintaining consistency of the MICE table wherever it is printed is to understand that the table is not a set of performance requirements. “It is really a description of a user’s environment,” Lounsbury notes. “When people see numbers in graphical form, they want test specifications and test procedures to go along with those numbers. The MICE table was developed as a user’s guide, not a set of performance requirements. That is one of the biggest misconceptions about the table.”

He further notes that the accompanying tutorial addresses measures the user can take, including isolation and separation techniques for networking equipment, that can mitigate the environmental conditions’ impact on a cabling system’s performance. Click here to view remainder of table.

Overall, it is fair to say the forthcoming TIA-1005 standard is in the final stretch of the standardization process. While some issues require additional ironing out, the essential structure and many detailed specifications are well-established.

Lounsbury says the TR-42.9 group is closely watching the progress of the proposed TIA/EIA-568-C set of standards, as they may dictate a change in the overall structure of TIA-1005. But because 568-C is still very much in the developmental stage, the creators of 1005 have not altered that document’s structure to accommodate the as-yet-unpublished 568-C.

PATRICK McLAUGHLIN is chief editor of Cabling Installation & Maintenance.