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St. Michael's College School; Toronto, ON List of Photos: 1.
Marble Arch at Student's Entrance
Project History and Background: The origins of St. Michael's College School (SMCS) date to 1852 when Bishop de Charbonnel established the school in part of his house on Church Street. After outgrowing its facilities, the school was moved in 1856 to Clover Hill which was donated to the Basilian Fathers by the Honourable John Elmsley. In 1881 SMCS was affiliated with St. Michael's College at the University of Toronto for post secondary education. Expanding at an incredible rate, a new wing was added in 1902 and the school remained at this location until 1950. (see photo) At this time, the school separated from the College and in September 1950 St. Michael's College School opened its doors in a new building located at Bathurst Street and St. Clair Avenue where it remains today. In September 2002 SMCS will celebrate its 150th anniversary. As part of a major redevelopment program in accordance with the school's Master Plan, several new construction stages were initiated to bring the school's systems up to Code and to equip it with the technology to keep its students current in many academic fields. Axiom Engineering was honoured with the opportunity to work on Stage 3 of the St. Michael's College School addition and renovation project. The school's academic program
and vision of its own future impressed us and we understood that this was
not just another school project. The networked classrooms, art and pottery
studios, computer graphics lab, fully-equipped darkroom, music rehearsal
and practice rooms, MIDI room, computer design labs, fabrication and prototyping
labs, and a fully networked research library represented a course curriculum
that spanned the traditional to leading-edge in scope. It was obvious to
us that the electrical power and lighting systems had to support and enhance
the qualities that made the project unique.
Electrical Aspects: Electrical Power Distribution System: Axiom Engineering's primary goal for the electrical distribution system was to provide a reliable source of power to the multitude of computer systems present throughout the building. The renovated areas were being completely stripped of the old systems and re-fitted to match the new areas. The non-linear (or non-sinusoidal) electrical load associated with computers, coupled with the high density mechanical loads required for the building's HVAC system presented an environment for serious power quality problems in the form of harmonic distortion and load imbalance on the power lines. The effects of harmonics could lead to: overheating of connectors and conductors resulting in fire or overvoltage damage; transformer overheating resulting in intermittent electrical noise that can corrupt digital signals as well as premature transformer failure; and failure of circuit breakers to trip properly resulting in a possible fire hazard and/or equipment damage. A common method of dealing with heavy computer loads consists of using K-rated (also known as zero-sequence) transformers to service computer panels. These transformers are considerably more expensive than standard units and while K-rated transformers are capable of handling excessive neutral currents in their secondary (low voltage side) windings, they do not address overheating of their primary (high voltage side) windings. We developed a solution for SMCS using properly-sized standard transformers to address the primary and secondary winding issues, without incurring the costs associated with K-rated units. Since the building was constructed in approximately 1950, the original electrical equipment and feeders would not have been sized adequately to service modern load densities. Furthermore, it has been common practice to utilize common-neutrals to service circuits. With this method, a single neutral conductor is used to service up to three circuits. In and ideal installation the neutral, by definition, carries almost zero current. However, this is only true when the load on each phase is almost perfectly balanced and linear in nature. This is seldom the case in most modern installations and it was obvious that the existing wiring and distribution systems had to be replaced within the renovated areas. Our design called for a robust electrical distribution system sized to accommodate the harmonic distortions expected from the non-linear nature of the electrical loads thereby increasing power quality and the life expectancy of the distribution equipment. By reducing the effects of harmonics, we also increased the available power capacity of the new and existing distribution systems. Data Communications: The entire school is extensively connected in terms of telecommunications infrastructure. Each classroom will have approximately six computers connected to the Local Area Network (LAN), achieved via a ladder tray system that runs the entire corridor length on each of the three building levels and interconnected between floors via multiple conduits. The ladder tray and conduit systems will also be capable of carrying fiber optic cable for future upgrades. The Odette Research Library is also fully-networked, providing the students with desk-mounted data outlets and power receptacles for their laptop computers as well as fixed desktop systems for research purposes. An additional set of computers is provided for searching the school's extensive archives. At the desk-end, we utilized a non-metallic raceway system with separate compartments for power and telecommunication wiring. In this way, any future work on the data cabling can be executed by the school's IT staff, without the danger of encountering electrical wiring. This also provides much more physical space to expand both the power and telecommunications installation without the need to install surface-mounted conduits and boxes. E-field Shielding: The load density of the building required approximately 675kva of transformation capacity from 600volt,3phase to 120/208v,3p,4w. We chose to locate all the 600volt distribution equipment and the three (3) 225kva transformers within a single electrical room located away from computer facilities and human presence. The electric and magnetic fields associated with electrical distribution equipment can adversely affect computer operation and some feel it may also be a health issue. After discussing the electromagnetic field issues and our concerns with SMCS, Axiom Engineering proceeded to design a cost-effective shielding system for the electrical room that would essentially trap the electric field generated by the equipment. Magnetic fields are very difficult to combat, however, increasing the distance from the source reduces their effect. Since the electrical room was located away from permanently-occupied areas of the school, we focused on reducing the electric field by creating a "Faraday Cage" around the inside perimeter of the electrical room, utilizing the steel deck at the ceiling and floor to complete the cage. The entire shield is then connected to an exterior buried grounding ring to dissipate the captured energy, safely discharging it to earth. Lighting Systems: To accommodate the varied tasks throughout the school, luminaires were selected to suit individual area requirements. Classrooms received recessed 3-lamp fluorescent luminaires while computer and graphic areas were specified with recessed 3-lamp deep-cell parabolic louvre fluorescent luminaires to reduce direct and indirect glare. The research library stacks and reading areas are lighted using indirect/direct pendant linear fluorescent lighting to provide softer illumination and to facilitate reading activities. Bulkheads were added between task areas of the library to serve as a cut-off shield to prevent reflected light from the indirect luminaires from bouncing into the field of view of the computer desk areas and at the perimeter to prevent glare from the full-height glazing. Emergency lighting was achieved using an AC inverter system that allowed the use of the normal luminaires to provide emergency lighting upon loss of normal power. This reduced the number of conductor and conduit systems we required and was much more aesthetically pleasing that the alternative of remote lighting heads installed at 30 foot intervals throughout the corridors. Having a central source of emergency power that has built-in diagnostics with remote monitoring capabilities also facilitates the maintenance and troubleshooting aspects of the emergency lighting system. Final Comments: SMCS was a textbook example
of teamwork between the Owner, Architect, the Engineers, Construction Managers,
and the construction trades. Axiom Engineering would like to congratulate
SMCS for their new leading-edge school.
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