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Schools rush in where contractors fear to tread

Rather than a catalyst for change, public education too often seems like a genie in a bottle: held captive by antiquated methods, inadequate funding, bureaucratic waste, and a timidity to accept new technology. If all of this is true, who will retool education for the electronic age? Fortunately, help is on the way-from outside the education bureaucracy.Various corporations and nonprofit organizations

Rather than a catalyst for change, public education too often seems like a genie in a bottle: held captive by antiquated methods, inadequate funding, bureaucratic waste, and a timidity to accept new technology. If all of this is true, who will retool education for the electronic age? Fortunately, help is on the way-from outside the education bureaucracy.

Various corporations and nonprofit organizations are stepping up to offer hand-and-deliver solutions to the education community-and these solutions may be coming just in time.

The education market, with more than 16,000 school districts that represent in excess of 110,000 schools, offers much opportunity for telecom cabling designers and installers. The cabling market for K-12 schools, in particular, offers the best business opportunity for contractors over the next six years. Interested contractors should learn how to bid high-performance cabling installations within school buildings.

Bear in mind, however, that the biggest hurdle to school telecom wiring is not technical, it's political. Successful installers understand business aspects of schools as well as the technical aspects of cabling systems. When you bid these jobs, be sure to set the contract price high enough to make up for the extra time required to negotiate and complete the selling process.

In spite of various administrative hurdles, many schools rush to get wired without a plan, and few budget funds for upkeep and replacement. With limited knowledge about the new technologies, school officials can easily make major mistakes in their projects.

A school must be committed to properly supporting the infrastructure. Even schools that budget funds for technology annually often fail to invest in computer experts who can keep their complex systems running smoothly. Fewer than one in 10 schools have hired full-time technology coordinators, according to a recent report by the Software Publishers Association.

Bob Fitzsimons, senior consultant at Information Transport Enterprises, New Canaan, Conn., knows the right path to take in wiring schools. He's been preparing design and specifications for school telecommunications systems (a major client is the Edison Project) since retiringa computer in every student's home. While a senior technical staff member at IBM Internal Telecommunications, Fitzsimons planned the information cabling systems and their applications for IBM's internal user community.

"Because we're doing work on buildings that have evolved over the last few decades, there is not a common electrical ground," said Fitzsimons. "There are four different kinds of everything in the structure. Then consider the physical construction, stone and masonry, brick, precast concrete, sheetrock, all in one site. About 85% of my time is spent determining the physical path for the cabling-conduit, sleeve, poke-through fitting, cable tray, etc. And, preparing the drawings and installing the pathway systems is where most of cost resides."

The most important point before doing any wiring is thorough up-front planning. A school district may say it is going to wire the buildings for all of the latest communications technology, but if they have not defined how the technology will fit into the overall curriculum, putting in the wiring may be a waste of time. For example, schools may plan doing rudimentary Windows in grades 1-3 and then teach word processing in grades 4-6. Administrations that don't plan a total concept will have a difficult time.

"In order to get a building properly wired for power, data and television (all three are important-and there has to be symmetry between data and power), you have to know what tasks will take place in each type of room," Fitzsimons said. You also need a corresponding electrical plan by type of room. Once these parameters and specifications are clearly defined, patterns can be repeated for other schools."Today the telecommunications wiring and the power contracts are awarded separately. I can see gaining better coordination of both services if they were combined; there is a (slight) trend in that direction," said Fitzsimons.

The use of a predesigned surface mounted raceway with two separate channels, one for low voltage wiring and the other for the associated ac power branch circuits, is being specified more than in the past. But the economics regarding its use is not always there; you don't often have a straight 30-ft wall surface for mounting a decent raceway section in an existing building.

"In regard to the branch circuit power for supporting the electronic equipment, I prefer to have an isolated grounding conductor in the system serving the receptacles," said Fitzsimons. "I have found that when the building has a properly installed grounding system, network system interrupts almost completely disappear."

To ensure that the building's electrical devices and copper communications equipment are at the same ground potential, a No. 3/0 stranded bare copper loop from the building's central ground point to the distribution frames is ideal. Surge suppression devices are also important at the subpanel and at the equipment outlet, especially in older buildings.

A school district serving 7000 students in grades K-12 implemented a Local Area Network (LAN) in each building and a Wide Area Network (WAN) across the district to bring Internet access to the classroom.

The EIA/TIA 568A Commercial Building Telecommunications Wiring Standard served as the basic concept for the design, but a carefully worded Request For Proposal (RFP) asked the consultant to use the standard as a starting point and to add further important concepts: such as "future proofing" and human-factor engineering.

The 568A standard covers the planning and installation of building wiring and the selection of the media (copper and glass fiber-optic cable) used to carry the signals. It allows a building to be wired with little or no knowledge of the communications products that will be installed, and it provides direction for the design.

Category 5 unshielded twisted pair (UTP) cabling is the most widely used media in the buildings. The UTP cable is constructed of four pairs of No. 24 AWG copper conductors with thermoplastic (insulated conductors enclosed by a thermoplastic jacket). This type of cable, which is characterized for frequencies up to 100 MHz, has become the mainstay for LAN applications in the United States and is expected to continue in that role.

The backbone is 12 strands of optical fiber from the main equipment room to each telecommunications closet (TC). Currently serving a Fast Ethernet network, the optical fiber will in the future support FDDI, or optical Gigabit Ethernet-or whatever protocol is developed.

Voice backbone cabling consists of multipair No. 24 AWG copper cable. Pair counts vary from 75 to 300 pair, depending on the serving area size for each TC. All voice backbone cable is terminated on patch panels rather than on Intermediate Distribution Frame punch down blocks in the TCs. This spec detail allows the same patch cords to be used for both voice and data circuits.

A broadband coaxial cable system carries television broadcast signals using Frequency Division Multiplexing (FDM) to transmit a number of channels, each on a different frequency. Two runs of RG-6U coaxial cable (one to receive and one to transmit) go to each classroom.

All backbone cable is installed in multiple 4-inch conduits connecting the main equipment room with associated TCs. All work area outlets are wired with four-pair Cat 5 cable installed in cable trays above the corridors and then in conduit for each classroom or office.

In each classroom, four outlets (two of the six remain blank) are installed on each of two separate faceplates. One faceplate is located on the corridor wall, and the other is installed near the visual aid board in the front of the room. Two other locations in each classroom are roughed-in, with conduit stubbed out above the ceiling. When additional jacks are needed, they can be wired with little disruption and minimum labor.

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