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Voice/data/video (VDV) cable plant has become the central nervous system of the customer’s business. It is necessary for producing and delivering your customer’s products and services. In addition, your customer’s VDV cable plant supports other critical building functions such as fire and life safety, security and access control, building automation and management. The VDV cable plant is key to your customer’s business and it must be maintained. This will become increasingly important as more and more production and building components become “smart” and need to be networked. When your customer’s network is down or is not operating at the level required, it impacts your customer’s business. It is important that your customer has a comprehensive VDV cable plant maintenance program and that they are aware of the maintenance activities that should be included in one.
What does your customer’s cable plant include?
An electric utility’s transmission and distribution plant does not just include the overhead conductors and underground cables that connect the generator to the load. It also consists of the overhead conductors and underground cables, along with all of the support structures and equipment needed to deliver power to customers.
The same is true for the VDV cable plant. It does not just include the copper and optical fiber cable that interconnects network equipment; it also includes its entire supporting infrastructure. This infrastructure includes raceway systems, grounding and bonding systems and equipment spaces, among other things.
What is there to maintain?
VDV backbone and horizontal cabling systems do not have any moving parts to inspect for wear and tear as other mechanical equipment in the customer’s facility. However, it still requires regular maintenance. Your customer’s VDV cabling plant is typically in a constant state of change because your customer’s business is also changing. This plant undergoes almost continuous change as it is adapted and reconfigured in the customer’s organization, reengineered business and production processes and the use of new technology.
VDV cable plant maintenance activities
Repair and warranty work. Repair and warranty work is an important part of maintaining the VDV cable plant, which can be damaged in a variety of ways such as lightning or accident during the normal course of business. When the VDV cable plant is damaged, it must be repaired as soon as possible. The electrical contracting firm’s ability to respond quickly to this need at any time is very valuable to the customer. Unfortunately, many customers think that repair and warranty work is the only maintenance work that needs to be performed. In reality, it is other ongoing maintenance activities that allow repair and warranty work to be completed in a quick and efficient manner minimizing network downtime.
Moves, adds, and changes (MACs). To be successful in today’s business environment a company must be agile and have the ability to change and reconfigure itself quickly to meet the demands of the marketplace. Your customer’s organization is probably in a constant state of change. As a result, the VDV cable plant needs to change as well. MACs are how the customer’s VDV cable plant is reconfigured on a day-to-day basis to reflect organizational changes. MACs are an important part of your customer’s ongoing VDV cable plant maintenance program.
Upgrade and replacement. If technology and the organization’s needs were constant, there would only be MACs. The same people and equipment would be shuffled and reconfigured to meet your customer’s changing organizational needs. However, technology continues to advance and the customer’s technological needs continue to change, which requires upgrading or replacing the existing plant.
While your customer’s VDV cable plant won’t wear out or deteriorate over time, it will become obsolete. The rate at which this occurs will depend on the customer’s industry, competitors and the ability to use new technology to its advantage. Customers in fast-paced and technologically dependent industries tend to place greater demands on their VDV cable plant, which typically results in shorter upgrade and replacement cycles than for other industries. However, even though the rate of change differs from industry to industry, one thing is certain—all industries are changing and your customers will need to upgrade and replace their VDV cable plant at some point.
Testing and evaluation. Ongoing cable plant testing and evaluation needs to be a part of your customer’s maintenance program. MACs, as well as upgrades and replacements, can shift network utilization patterns and overload parts of the system, slowing data transfer rates and causing other network problems. In addition, your customer needs to know if its existing VDV cable plant can reliably support the demands of users and new technology.
VDV cable plant evaluation should not only consider the backbone and horizontal cabling systems’ performance, but also the infrastructure that supports the cabling. This should include raceway and cable tray usage, space utilization in equipment rooms and closets, the quality and reliability of the electric power supply to equipment, the adequacy of grounding systems and the physical environment in which equipment and cabling is placed.
Documentation and inventory. The documentation of the VDV cable plant and inventory of all equipment connected to it should not be overlooked. Without documentation in the form of cable and pathway schedules, it is difficult to know where individual cables originate and terminate, how they are routed through the facility and if spare cable capacity is available for expansion, among other things. Similarly, knowing what equipment is connected to the network and where it is located is also important to understanding the network layout and its use.
Documenting the VDV cable plant and keeping this information up to date on an ongoing basis is an investment that will pay dividends. All cable, network equipment and pathways should be physically marked with a unique identifier that can be used to determine what it is, who manufactured it and where it is located. In addition, all network cabling, equipment and pathways comprising the customer’s VDV cable plant should be catalogued by an electronic or paper database. Record drawings should also be kept up to date showing cable pathways and the location and layout of equipment closets and spaces. Operation and maintenance information, shop drawings, catalog cuts, test reports and warranties and guaranties, along with other information about the VDV cable plant should also be filed.
Documenting the customer’s VDV cable plant, including an inventory of all equipment connected to it, will improve network reliability and save money. Detailed documentation will speed system repairs and minimize downtime; make the planning and execution of MACs more efficient; and provide the basis for planning system upgrades and replacement. Documentation must be an ongoing part of the maintenance program. The documentation and inventory must be updated continuously, because if it gets outdated it will be useless and very expensive to update.
Safety and code compliance. As part of the VDV cable plant maintenance program, the plant should be inspected regularly to ensure that installation is safe and in compliance with local codes and insurance requirements. Customers typically have numerous networks spread throughout their facility that may or may not be interconnected. Network cabling and equipment are often installed in the customer’s facility by its own employees, equipment vendors and other outside installers who may not understand the specific safety issues and the need to adhere to local codes and industry standards.
To inspect the system for safety and code compliance, cables should be checked to ensure that they are suitable for the application. For instance, plenum-rated cable needs to be installed in air-handling spaces, including above the ceiling return-air plenums. All penetrations need to be sealed with approved fire-stopping material to contain smoke and flames in the event of a fire. In addition, equipment-grounding connections need to be checked and verified.
The first step in establishing an effective VDV cable plant maintenance program is to educate your customer about the need for and benefits of maintaining his or her cabling system. Your customer’s VDV cable plant is important and must be maintained to ensure good and reliable service throughout its useful life. EC
Acknowledgement
This article is based on the research project entitled “Effective Service Strategies” that is being sponsored by the Electrical Contracting Foundation, Inc. The author would like to thank the foundation for its continuing support.
GLAVINICH is an associate professor in the Department of Civil, Environmental & Architectural Engineering at The University of Kansas. He can be reached at 785.864.3435 or [email protected].
About The Author
Thomas E. Glavinich was an associate professor in the Department of Civil, Environmental and Architectural Engineering at the University of Kansas. His tenure as one of Electrical Contractor's most trusted and reliable source of industry research ended in 2014 when he passed away. Click here for more about Tom.