Power Play

Over the past five years, the importance of technology in educational facilities has increased dramatically. Today, technology cabling must be thought of as a basic component of school-building infrastructure, much like electric power or plumbing. Integrating technology at that level is not particularly difficult in new construction, but some interesting challenges arise when dealing with older buildings.

Administrators must consider a number of things when adding technology to older facilities, including: *Network infrastructure. *Space planning. *Environmental considerations. *Accessibility. *Security. *Aesthetics. *Electric power to operate computers and other equipment.

Equipment that comprises technology infrastructure must be located properly. This equipment includes the main and intermediate distribution frames, as well as network electronics such as hubs, routers, servers and media-retrieval equipment. The network infrastructure plan must take into account the distance limits of cabling runs and the physical security of the various devices.

Coordination of network drop locations and electric power outlets also is important. If both electrical outlets and network drops are being installed, dual-channel raceways can be surface-mounted on the walls to contain data cable and electric wiring. This improves the appearance and the coordination of the construction, and can make the work a little less intrusive in an older building.

Another impact of adding technology to facilities involves the need for adequate ventilation and cooling. This has less to do with the operational tolerances of the equipment than with human comfort. An additional ton of air-conditioning capacity is required to offset the heat produced by 61/2 computer workstations, because a computer adds seven times as much sensible heat to a room as the person working at it.

Another group of environmental considerations might be loosely classified as space-planning issues. These issues are not unique to older buildings, but they may be more difficult to resolve given existing conditions. The most obvious issue is deciding where in a space the computers and network drops are to be located. From an instructional perspective, prevailing wisdom is to locate the technology where (and wherever) learning occurs. This is not always the most feasible location from a facilities perspective. A balance should be sought with a high value placed on flexibility. Glare from natural and artificial light sources also should be considered when locating computer screens.

A common pitfall Next to the network cabling, providing safe and adequate electric power should be the top priority during technology implementation. Yet, this often is overlooked. For instance, there are a number of state and federal funding initiatives such as the e-rate and volunteer programs like NetDay, which aim to help schools with technology. While these focus on providing computer workstations or network cabling, often they ignore issues such as electric power upgrades, which often can cost five times what the network infrastructure does.

Many of the building codes that govern electrical power systems are based on the National Electric Code (NEC). NEC regulations state that a maximum of 80 percent of the rated capacity of a building's electric power system can be used. A typical electric power circuit in a school building is 20 amps; therefore, there are 16 amps of usable capacity. This is roughly the equivalent of two to three computer workstations and a shared printer.

Many older school buildings do not have a surplus of electric power. It is not at all unusual, though, for a given classroom to have only a couple of electrical outlets, or for multiple classrooms to be on a single electric power circuit. Adequate circuits must be provided if the school is to comply with the governing codes.

Determining electric capacity Determining the actual capacity of a school's electric power system can be a difficult process that requires a professional. The first step is to examine the capacity of the main electrical service entrance to the building. This information may be available from maintenance staff, the electric utility company or it can be determined by an electrician. It is important to note the capacity of the conductors and switches inside the main power panel(s) because it may be lower than the rated label of the panel itself. Again, the NEC limits usage to 80 percent of this capacity number.

The second step is to examine the building's electric-power usage. The local utility company should be able to provide the maximum number of kilowatts drawn over each of the past 12 months, and the school will be governed by the peak usage. They also should be able to help relate this number to the capacity of the service entrance.

By comparing the peak usage with the capacity of the building service, it should be apparent whether the building has spare capacity, or if it is at or over code-allowed capacity. It is important to note thatthis is just a ballpark figure on a building-as-a-whole level. Even if the building has adequate power, it may not have a distribution system that supplies the power to areas where it is needed. That detailed information should be developed by an architect or engineer, and may be the first step in designing necessary facility upgrades.

Making upgrades Several things should be kept in mind when planning upgrades. The first is to plan now for the future and provide additional capacity for possible needs such as HVAC upgrades. Second, it is desirable to provide dedicated power service for technology equipment that is separate from the other outlets. Dedicated outlets (usually color-coded orange) are on a separate distribution system with an isolation transformer and provide "filtered" or clean power so computers are not affected by other devices.

Another advantage of dedicated electrical service is that the size of the neutral wires can be increased to reduce the possibility of them burning out. Neutral conductor burnout is a problem that may disrupt existing electrical systems not designed for electronic equipment like computers.

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