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Compliance: The design and constructionof all building electrical systems shall be incomplete compliance with the currentadopted revision of the National ElectricCode. This code is to be viewed as thefinal authority for establishing the minimumrequirements of electrical devices,equipment and systems. The requirements

of these documents often exceed theminimum requirements of the Code. Whenthey do, they shall be complied with.

Transformer Rooms: Each building shallincorporate one or more transformer rooms(see the Equipment Rooms, Electricalsection within these General Guidelines).These should generally be located on thelowest level of the building, adjacent to theelectrical service entrance. This room shallhouse the buildings transformer(s), switchgear and associated equipment.

Unit Substations: When the designmaximum demand is approximately 150KVA or more, the transformer andswitchgear shall be of the unit substationtype, with all components in one factoryassembled unit. Each unit substation shallconsist of a primary switch section,transformer section, main fused switchsection and secondary distributionsection(s). The secondary distributionsection does not need to be the same depthas the rest of the unit substation or attached,

and it can be of the switchboard type. Allunits shall be front aligned. (See Sections26 11 16 Secondary Unit Substations and26 22 13 - Transformers for requirementsand sizing criteria.) The main switch sectionshall incorporate metering (see Section 2627 13 Electric Metering).

Smaller Buildings: In smaller buildings, asingle unit substation shall be installed thatsupports the building loads. A 277/480 volt,three-phase, four-wire system to servelighting and mechanical equipment shall beutilized with a 208Y/120V to supportreceptacle loads. This is preferred and shallbe done when the project budget cansupport it. It is preferred to install one ormore motor control centers to servemechanical equipment, in lieu of installingdistributed motor starters, when it is costeffective to do so and the project budget cansupport it.

Transformer Redundancy: A building withexpected maximum demand of over 750KVA, generally, shall have two separatemain transformers of equal capacitieslocated either in separate transformer roomsin different parts of the building or in adouble-ended arrangement in onetransformer room. This is recommended for

reasons of safety, reliability and equipmenthandling. Buildings with large auditoriumsor assembly areas shall have twotransformers as required to insure reliabilityof the lighting.

Overcurrent Protection / Coordination:Each overcurrent protective device shall beproperly sized for the protection of theconnected downstream component. Fusibleswitch type equipment shall be used whererequired. All protective devices, includingthe primary fuses, the secondary main

protection device and the secondarydistribution protection devices shall becoordinated for a purely selective system.

Harmonics: Electrical design shall takepower system harmonics into consideration.Each transformer shall be K factor ratedwhere applicable.

Panels: Each distribution panel locatedwithin the building shall be served by adedicated circuit breaker within thedistribution section of the unit substation.

Distribution and branch panels may belocated in electrical closets that are directlyaccessible from a public corridor. Theseclosets shall be labeled Electrical. Theymay also be located in public corridor wallsand, if so, shall be flush-mounted. Eachpanel shall only serve electrical devices thatare located on the same floor as the panel.The only acceptable exception to this is anemergency panel, which may serve multiplefloors. Branch panels shall be located suchthat branch circuits will not exceed 100 ft. intotal developed length. Each flush-mountedpanel shall be fitted with four spare 1 in.conduits that extend above the suspendedceiling or to a point near the structuralceiling. Each new distribution or branchpanel shall have 42 spaces and shall have aminimum of nine spare spaces when theentire installation is complete.

Emergency Panels: Generally, theemergency panel(s) shall be located in the

U OF I FACILITIES STANDARDS ELECTRICAL SYSTEMS, BUILDINGADDENDUM NO. 2 LAST UPDATED NOVEMBER 1, 2011REVISED DOCUMENT

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ELECTRICAL SYSTEMS, BUILDING

main electrical room and shall serve onlyexit and emergency lights along with othercritical equipment as deemed appropriateand necessary.

Circuiting: Wall outlets shall be served by20 Amp circuits with a maximum of sixduplex outlets per circuit. Lighting and

outlets shall be served by separatededicated circuits. No shared neutrals shallbe allowed anywhere on campus. Circuitsthat serve outlets located in corridors shallserve corridor outlets only. They shall notalso serve outlets located in other spaces(e.g. offices or laboratories where computersor other critical equipment may be inoperation). These outlets are used bycustodial staff to power cleaning equipment,resulting in the occasional tripping of acircuit breaker. Each substantial piece ofhard-wired single-phase electrical

equipment shall be served by a dedicatedcircuit. Every piece of hard-wired three-phase electrical equipment shall be servedby a dedicated circuit. Equipment thatincorporates duplex units for the sake ofredundancy such as air compressor units,sump pump units and condensate pumpunits shall be served by two separate powerand control circuits such that one unit cancontinue to operate when the other hasfailed. Each piece of equipment or systemshall be served by a dedicated control circuitthat is wired so as to be disabled when the

power circuit is disabled. Standard controlcircuits shall be 120 volt.

Outlets: The density of portable electricaldevices used within University buildings,especially laboratory buildings, is quite high.

Also, the usage of spaces changes often.Therefore a generous number/distribution of20 Amp duplex outlets shall be provided innew or remodeled areas. For example,even the smallest and simplest office areashall have at least two duplex outlets. A 20

Amp duplex outlet shall be provided every50 ft. (maximum) in corridors and publicareas for use by custodial staff. Mechanicalequipment rooms, electrical equipmentrooms, elevator machine rooms, janitorclosets and other service and support areasshall not be overlooked with regard to theneed for an adequate number/distribution ofoutlets. The location of outlets shall becoordinated with the layout of modularfurniture/partitions with integral raceway.

Generally, outlets shall be flush-mounted inwalls. Flush-mounted floor outlets are notallowed. However, recessed floor boxeswith hinged/removable covers that containpower and/or voice/data receptacles may beinstalled to serve equipment that is locatedremotely from the nearest wall.

Exterior Outlets: An exterior outlet shall beprovided adjacent to each piece (orgrouping) of mechanical equipment (at theground and roof levels) to facilitate service.

Motor Starters: Each three-phase motorshall be served by a magnetic starter with ahand-off-auto switch, as opposed to amanual starter. This facilitates the futureapplication of automatic controls.

Flexible Design: As mentioned previously,the usage of spaces within University

buildings, especially laboratory spaces,changes often. Remodeling is a commonoccurrence. Therefore, the buildingelectrical systems shall be designed withsufficient flexibility and spare capacity toaccommodate substantial future changes.Generally, a spare capacity of 25%(minimum) shall be provided throughouteach electrical system, from the reservetransformer capacity to the number of sparespaces in each branch panel.

Panel Identification label: Every electrical

unit substation, switchboard, automatictransfer switch and panel shall be identifiedwith a label designating the building number,the room number where the equipment islocated, and the room number where theequipment is fed from. (For example: if alighting panel is located in building 0014,room 435 and fed from a unit substation,located in room # 12 in the basement, thenthe panel will be labeled as 0014-LP435-12).See F&S Engineering Services for additionalinformation in regard to equipment labels.

Design Coordination: The ContractDocuments shall provide completeinformation in regard to the electricalmetering for the Project at not later than the50% design review. This completeinformation shall include location, one linediagram, and specifications.

U OF I FACILITIES STANDARDS ELECTRICAL SYSTEMS, BUILDINGADDENDUM NO. 2 LAST UPDATED NOVEMBER 1, 2011REVISED DOCUMENT

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