Proposed Campus Wiring Standard

• Description and Appendix Specification
• Work Station Wire and Termination
• Terminals and Sub-Terminals

Description and Appendix Specification

The following elements of the campus specifications are general and refer to the components of the wiring standard in which they are used. Detailed specification, and technical or illustrative drawings are contained in the Appendices for this document.

Conduit versus Plenum-rated Direct Placement Cable

The Communications Services document Construction Standards for Communications Services at UCSB, revised December 1992, specifies the placement of electrical metallic tubing (EMT) conduit to house communications cabling. This conduit is continuous, or "homerun," between the workstation outlet and the serving sub-terminal. In appropriate environments, the conduit may be terminated at a common overhead cable tray and the workstation cable continued through the tray to the sub-terminal.

It has been a common practice on this campus to place cabling without conduit by entering walls and ceiling areas and routing cable point-to-point between workstation and sub-terminal. With the implementation of the 1988 Revision of the National Electric Code (NEC) all such cable in walls and ceilings must conform to a sheath standard, such as plenum-rated (e.g. CMP or CL2P).

It is recognized that cable placed without conduit can cost less and sometimes be placed faster then cable that requires the installation of conduit. The campus has placed a high priority on making network attachments available as widely as possible. With a limited amount of funding for attachment wiring, the placement of cabling without conduit has been essential to provide the widest possible connectivity. Nonetheless, conduit will continue to be required as a campus standard for all new installations and major remodeling and it is recommended that limits be placed on the use of non-conduit cabling.

The use of conduit is supported by three considerations:

1. Conduit provides physical protection of the communications cable and, therefore, supports the reliability of the communications link. The above-ceiling areas in which plenum cable is currently placed is also the location of air conditioning, heating, plumbing, fire sprinkler, and other utilities. Maintenance of these utilities requires access by service personnel with subsequent risk to communications wiring.
2. Conduit provides a path in which cable may be placed, removed and replaced. Augmentation or upgrade of cabling is done quickly and cheaply with conduit. The equivalent tasks with non-conduit wiring requires ceiling access which carries the additional responsibilities of repair or replacement of ceiling tile, dust control, and risk to structural or other utility functions carried in the ceiling.
3. Metallic conduit provides protection against electrical interference from power, control signaling, and lighting fixtures. While the unshielded twisted-pair standards of current telephone and 10BaseT cabling can minimize electrical interference, the technology required to use unshielded pairs at higher speeds brings with it both distance limitations and increases in attachment costs. Such limitations and costs are quite reasonable with the current 10BaseT technology, but may rise sharply with the higher speed (100 MBps) of copper distributed data interface (CDDI). The use of conduit will minimize the impact of electrical interference on unshielded twisted pair cable.

Plenum-rated cables placed without conduit in ceilings shall be used in lieu of new conduit in existing buildings only when the placement of new station conduit is not possible due to costs.

Conduits and Cable Tray

In some new buildings, the use of overhead cable trays may be used to distribute communications cabling between sub-terminals and from subterminals to workstations conduit access. Conduit will be placed to link in-wall workstation outlet boxes with the cable tray. Workstation cabling will run through the conduit and into the cable tray and in the cable tray to the serving sub-terminal and patch panels.

Plenum Cable and Cable Tray

Per the National Electric Code, 1996 Revision, all cables contained within cable tray are to be plenum-rated. This includes cables which enter or exit a cable tray from a conduit or terminal no matter what footage resides in the cable tray vs footage in conduit or at a backboard.

Plenum Cable and Within-Wall Drops

Cable should be "dropped" to the station attachment wall plate by placing the cable inside of the wall, entering the wall plate from the back. This method may result in higher costs than surface-mounted wiremold and should be balanced with the needs for the physical appearance of an installation.

Station attachment wall plates shall be mounted a standard (ADA) eighteen inches (18") centered above floor line.

Plenum Cable and Surface Raceway

If cable cannot be placed within a wall due to internal barriers or restrictions, cable shall be placed within surface raceway from ceiling penetration to a surface wall box. All raceway components shall be physically secured to the wall and to each other. Adhesive-mounted or metallic screw-mounted raceway may be used. It should be noted that adhesive-mounted raceway, upon removal, can cause substantial damage to paint and wall surface.

Station attachment wall boxes shall be mounted a standard (ADA) eighteen inches (18") centered above floor line. Installation of raceway may require painting of the exposed surfaces to match existing room color.

Cable and Above-Ceiling Cable Wireways

In the late 1990’s, manufacturers introduced wire-frame and plastic flexible wireways designed to carry individual cables in the areas above ceilings and below computer floors. The wireways could be supported by ceiling or wall-attached mounting and were designed to be shaped around obstacles such as air conditioning ducts, electrical fixtures, etc. The most common use of these wireways is in manufacturing and open office environments where no drop ceiling exists and the wireways are generally accessible.

Individual station cables are routed into these wireways by either conduit or surface-mount wiremold. Once in the wireways, the cabling is supported at frequent intervals (4" min to 12" max) throughout the run. Cables can enter and exit the wireway through the open face or at specific angled or T-drop exits.

The use of flexible wireways has been tried on campus and may be appropriate in some limited circumstances. It should be noted that the wireways provide a method of grouping above-ceiling cabling, but have the problem of access common to any non-conduit installation. In addition, such wireways are not fire-rated to pass through code-rated walls and an intervening duct sheath or fire barrier must constructed in such locations.

Workstation Wire and Termination

It is proposed that UCSB adopt the EIA/TIA-568A wiring standard for communications as follows.

1. All workstation cabling will conform to the EIA/TIA 568-A, TSB-40A and TSB-36 for the 5e performance specification.
2. Three (3) four-pair cables will be placed to each workstation. A composite cable with three (3) four pair cables in a single enclosing sheath may be used. While a composite cable is still acceptable under the 5e performance adoption, the next generation of standard proposals and campus initial installations with fiber to the desktop will necessitate the use of individual cable sheaths. We recommend that all current and future installation projects use individual cable sheaths.
3. Each of the four-pair cables will terminate on a dedicated RJ-45 jack with integrated 110 type connectors using the 568A specification for pair termination. The RJ-45 connectors may incorporate circuit board wiring which supports either "A" or "B" standard depending upon punch-down sequence of the cable pairs.
4. All RJ-45 jacks used in campus cabling systems will meet or exceed the EIA/TIA 568A, TSB-40A and TSB-36 Category 5e performance specifications.
5. The wall plate shall identify the jacks as Data 1, Data 2, and Voice (D1, D2 and V1).

New Construction

All new construction shall use cable meeting the performance specifications of EIA/TIA-568A, TSB-40A and TSB-36 Category 5e standards for data and telephone single-line or digital key systems.

For maintenance or expansion of an existing analog (10A2) key system, the PBX 25, and 50 pair cables used shall meet or exceed the performance specifications for Category 3 cable defined under the EIA/TIA-568A standard. While this latter cable may be placed for use with analog telephone systems, the Category 3 specifications assures that the cabling, including spare pairs in working phone cables, will be usable for 10BaseT (Category 3) speeds.

Addition to Existing Installations

Data and single line or digital key systems telephone cabling added to existing installations through existing conduits shall use four-pair unshielded cable which conforms to the EIA/TIA-568-A performance specification. These cables will meet the Category 5 performance specification. PBX cables for use by analog (10A2) key systems shall continue to meet the (10BaseT) EIA/TIA-568-A Category 3 specification.

Addition of Fiber

A pair of 62.5/125 um dual window multimode fibers in a separate tight sheath cable can be added to any workstation outlet should the proposed equipment attachments require fiber. Termination of these fibers will be on ST-connectors attached to ST barrel connectors in a replacement wall plate which will also support the RJ-45 jacks described above. Termination of the fibers at the sub-terminal end will be on a dual access termination panel with ST barrel connectors.

The use of fiber (multimode) to the desktop may be added to renovated and new building construction. If the fiber is terminated, in the absence of a national or campus standard for termination, Communications Services recommends that the MT-RJ connector be used and that the form be the Siecor MT-RJ or equal. The MT-RJ form supported by Siecor, AMP, Hubbell and others uses a standard RJ-45 cut-out. Thus, the MT-RJ jack can be inserted in the space already allocated to the ‘spare’ fourth RJ-45 jack on existing faceplates.

In existing installations, a separate surface-mounted box will be used for termination and access to the fibers.

To meet the placement requirements for fiber to the desktop, Communications Services recommends the use of angled or recessed wall plates. Several implementations of such wall plates exist and at least one current campus project has implemented the angled face plate and fiber design.

Composite Fiber and Twisted Pair

Subject to the continuing evaluation of per footage costs, composite workstation cables containing twisted pairs and fiber strands shall be considered for new building installation. The decision to place fiber to the desktop in this composite cable shall be based on:

1. Equivalent cost + 30% of the current EIA 568 Category 5e cable per foot cost.
2. Determination of probable use by the workstation occupants within two years of installation.3. Communications Services recommends that the MT-RJ connector be used and that the form be the Siecor MT-RJ or equal. The MT-RJ form supported by Siecor, AMP, Hubbell and others uses a standard RJ-45 cut-out.

Wall Plates

All workstation termination wall plates shall use modular RJ-45 jacks with integrated printed circuit integrated 110 type connectors conforming to
EIA-568A Category 5e performance specifications.

The use of fiber (multimode) to the desktop may be added to renovated and new building construction. If the fiber is terminated, in the absence of a national or campus standard for termination, Communications Services recommends that the MT-RJ connector be used and that the form be the Siecor MT-RJ or equal. The MT-RJ form supported by Siecor, AMP, Hubbell and others uses a standard RJ-45 cut-out. Thus, the MT-RJ jack can be inserted in the space already allocated to the ‘spare’ fourth RJ-45 jack on existing faceplates.

Jumper Cables

Terminals and Sub-Terminals

Sub-Terminal Patch Panels

All workstation cabling will terminate directly on modular patch panels within the serving sub-terminal. The patch panels shall be EIA-568A Category 5e rated with 110-type wire termination strips supporting RJ-45 jacks using an integrated printed circuit interface. The patch panel jack will mirror labeling information for the wall plate jack.

The three RJ-45 jacks on the wall plate will be mirrored on three separate modular patch panels, allowing each patch panel to support common attachments, e.g. Data 1 jacks, Data 2 jacks, and Voice jacks. A unique number at the wall plate will match the patch panel numbering series at the sub-terminal.

Either individual or common 19" hinged swing gates should be used to support the patch panels. Workstation cable shall be supported on backboards behind the swing gate and patch panels and individual cables routed to the patch panels from the hinged side of the swing gate.

NOTE: No intermediate terminal blocks (e.g. 66-type) or cables (e.g. telco 25 pr amphenol) will be used for workstation cabling under this wiring standard.

Patch Cables

All patch cables at patch panel-to-host attachments will use RJ-xx Modular cables with specifications conforming to the performance category of the attachment. Thus, even though a new wiring installation uses Category 5e cable and RJ-45 jacks, the modular patch cables for a 10BaseT LAN running on this cable and patch panel would meet Category 3 performance specifications. The use of lesser rated patch cables is justified by significantly reduced costs without loss of required performance (e.g. 10 megabits per second).

It is critical to note that the current Category 5e specification does NOT include a jumper cable component. Thus, while new wiring from terminal space to workstation jack may be 5e-rated, the jumpers at the terminal and workstation cannot exceed the existing Category 5 rating.

Riser and Lateral Inter-Terminal Cabling

All backbone network services will be extended from the main building terminals to each sub-terminal via riser and lateral cable paths. Telephone trunking cables will meet the Category 3 performance specifications and continue to terminate on 66-type blocks.

For support of inter-terminal LAN Hubs, multiple, individual units of EIA-568 Category 5e-rated cabling may be placed between adjacent hubs. Termination may be on 568-A Category 5e RJ-45 jacks or on a Krone Category 5e-rated terminal block.

Twenty-five pair cables at Category 5 and current 5e performance standards are in common use. Termination of these cable must be on matching Category 5e devices, including Category 5e jack patch panels and Krone 8-pair and 10-pair Category 5e blocks.

Coaxial cable for CATV services will be placed to each sub-terminal with required splitters and taps for network access.

Concurrent with the adoption and modification of this campus wiring standard, all communications terminals and sub-terminals constructed or expanded shall include provision for fiber innerduct, multi-mode fiber cables and associated terminating hardware. These facilities shall be placed so as to enable future fiber attachment of the sub-terminal with the sub-terminals or main terminals in the adjacent vertical or horizontal link.

A minimum of two (2) one-half inch (.050") or two (2) three-quarter inch (0.75") flexible innerducts shall be placed between each terminal and sub-terminal subject to space available. All new construction will incorporate capacity for multiple innerducts.

The three-quarter inch (0.75") flexible innerduct is required for tight-buffered composite fiber cables which use separate interior jackets for both multimode and single mode fibers.

DCC