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| Division 16 Electrical |
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| 16-2 | Basic Electrical Materials And Methods |
| A. | Conduit |
| 1. | Specify rigid steel, galvanized, or sherardized conduit. Aluminum may be specified for rigid conduit larger than 1-1/4" IPS in dry locations, provided suitable precaution is taken against physical damage during construction. Non-metallic conduit and intermediate metal conduit are allowed underground in concrete envelope. |
| 2. | In general, enclose underground conduits and ducts in a red-dyed (high voltage only) concrete envelope. Duct banks shall have steel reinforcing bars of proper size and spacing. Trenching, backfilling and concrete work to be done under that section of the work. Use plastic conduit for Main Power and Telephone Underground Feeders, or if directed by Planning, Design and Construction (CP), rigid steel conduit, protected with plastic tape wrap or plastic coat in thickness as specified in lieu of concrete envelope. Specify factory wrapping or .020" thickness, 1/2 tape width overlap if field wrapped. |
| 3. | Use rigid conduit with threaded couplings in concrete slab or wall construction. Electrical metallic tubing with insulated throat connectors may be used in furred spaces and areas not subject to damage and in sizes not over 2". Specify steel compression locking ring type connectors. Set screw or indenter type fittings are not acceptable. |
| 4. | Use flexible steel conduit for connection to all movable motors and to vibration producing equipment. Specify sufficient length to provide for anticipated movement and to prevent transmission of any vibration to the building. Use flexible steel conduit for light fixtures in suspended ceilings. Specify use of liquid-tight flexible conduit for all damp or wet locations. Flexible steel conduit may be used on rehabilitation work only where rigid conduit is not possible or practical to install. Discuss all proposals for this use with Planning, Design and Construction (CP). |
| 5. | Keep conduits within the furring lines established on the architectural drawings, unless conduits are shown exposed. |
| 6. | Provide all necessary sleeves and chases required where conduits pass through floors or walls. Seal all openings with approved fire stopping material to maintain integrity of wall or floor being penetrated. Finish to match adjacent surfaces after installation. |
| 7. | Do not locate conduit in the following construction: |
| a. | In concrete slab where conduit has an outside diameter greater than one third of slab thickness. |
| b. | In a concrete slab less than 3-1/2" thickness. Local offsets are an exception. |
| c. | Between concrete slab reinforcing steel and bottom of slab. |
| 8. | Install sealing fittings on conduits penetrating walls of cold rooms. |
| 9. | Run all exposed conduits parallel to building walls and ceilings. |
| 10. | Support conduit runs to structure with clamps, hangers, or trapeze spaced according to code requirements. Conduit raceways shall not be supported by other building piping systems. |
| 11. | Support vertical conduit runs by means of adequate clamps at each floor, or as required by code. |
| 12. | Use 3/4" minimum conduit size for power wiring. Switch legs may use 1/2" size. |
| B. | Wire, Cable And Bus Duct |
| 1. | Specify 600 volt copper NEC standard conductors with Underwriters' label, for secondary power and light distribution. Color coding, application and types as listed below. Deliver to job in unbroken packages. |
| 2. | Requirements for copper conductors only: |
| a. | Color coding shall be as follows: |
| Voltage | Phase | A | B | C | N | GROUND |
| 120/240 | 1 0 3W | black, red | none | none | white | green |
| 120/208 | 3 0 4WY | black | red | blue | white | green |
| 120/240 | 3 0 4W | black | orange | blue | white | green |
| 277/480 | 3 0 4WY | brown | yellow | purple | gray | green |
| 480 | 3 0 3W | brown | yellow | purple | none | green |
| Insulated equipment grounding conductor - green. |
| b. | Provide type THWN or THHN wire and cable #4/0 AWG size and smaller in dry locations. |
| c. | Provide type THWN wire and cable larger than #4/0 AWG size in wet locations. |
| d. | Provide type RHW, THW or XHHW wire and cable larger than #4/0 AWG size installed in damp locations or in concrete in contact with the ground. |
| e. | Do not use conductors smaller than No. 12 AWG for lighting or receptacle circuits. |
| f. | Low voltage wiring shall be No. 14 AWG size or larger. |
| g. | Fire alarm detector wire shall be type TFN, 18 AWG SBC MAX OPER V. 600 solid or maximum of seven strands. Fire alarm annunciator lamp wires may be No. 20 AWG if cabled. |
| h. | Wire pulled in flexible metal conduit shall be stranded when flexibility is required. |
| i. | Specify separate ground conductor as being mandatory in all branch receptacle circuits. (This exceeds code requirements.) |
| j. | Specify copper bus duct with silvered joints. |
| k. | High voltage cable (4160 volt and 12000 volt systems) shall be 5KV and 15KV, EPR type, with 133% insulation and shall be warranted for 40 years. Specify Kerite and Okonite cable or equal, minimum 4/0 size. |
| C. | Wire Joints And Connections |
| 1. | Specify all connections to circuit breakers, switches and joints in wires as follows: |
| a. | Connections to Circuit Breakers and Switches: No. 12 wire ‹ formed around binding post or screw. No. 10 and No. 8 wire ‹ Buchanan Termend, or equal, locking tongue lug. No. 6 wire and larger-Burndy Qiklug Type QDA, Penn Union, or equal, round flange solderless lug. |
| b. | Connections to Fixtures: Make circuit wiring connections to fixture wire with insulated electrical spring connectors. Threaded-type wire nuts, porcelain or bakelite are not acceptable. |
| c. | Wire Joints: No. 6 and larger ‹ Burndy Type QPR, Penn Union, or equal. No. 8 and smaller - pigtail splices as described below, or made with insulated electrical spring connectors. |
| d. | Where underground and high moisture area connections are required to be insulated, use approved moisture-proof epoxy resin splicing kits. |
| e. | Insulate uninsulated solderless connections for wires to the same insulation values as the conductors. |
| f. | Apply to the conductor in each junction or pull box used in 277 VAC lighting conduit runs, a 1" diameter red tag, reading Caution ‹ 277 VAC |
| D. | Outlets |
| 1. | Use cast metal conduit bodies with threaded hubs for outlets in exposed wet and/or hazardous locations and sheet steel boxes with sherardized or galvanized finish in concealed locations. |
| 2. | Sheet steel boxes ‹ standard one-piece knockout boxes of the shape best suited to the particular location and of sufficient size to contain all wires and connections without crowding. Where outlets are installed in concrete slabs, use concrete type boxes of depth sufficient to avoid interference between reinforcing bars and conduit runs, and to keep such conduit runs in proper place in slabs. Do not use boxes less than 4" square and 2-1/8" deep except concrete ceiling outlets may be 4" octagonal. |
| 3. | Cast-metal conduit bodies ‹ Crouse-Hinds condulets, Appleton unilets, or equal. Arrange boxes with threaded connections for rigid conduit. Provide all conduit boxes with suitable covers and gasket for all exterior and moist locations. |
| 4. | Support all boxes with approved box support brackets (side box fastening not acceptable). |
| E. | Receptacles And Caps |
| 1. | Specify receptacles and caps in accordance with National Electrical Manufacturers Association (NEMA) standards. Where weatherproof mounting is required, mount in a cast metal conduit fitting and cover with gasketed, spring type, door. See this division for ground fault protection requirements. |
| 2. | Specify hospital-grade receptacles for patient contact areas. |
| 3. | Colors and finishes for receptacles shall be specified as selected by the architect. |
| 4. | Specify the height of each outlet as 18" above floor to conform with physically handicapped regulations or as indicated on the drawings. |
| 5. | Install receptacles with the grounding slot at the top for vertical plate installations and with the ground slot at the left for horizontal plate installations. |
| 6. | Receptacle circuits shall not be dependent upon device connections for continuity except circuits that are terminated at the receptacle. |
| 7. | Install receptacles in mechanical rooms and at roof mounted equipment so that no piece of equipment is more than 25' from a receptacle. |
| 8. | Provide special receptacles as required by specific equipment. |
| 9. | Identify all receptacles connected to emergency power. |
| F. | Tumbler Switches |
| 1. | Specify quiet type flush mounted wall type tumbler switches rated at 20 amperes, 120-277 volt AC, screw terminals. Specify color and finish as selected by the architect. |
| 2. | Attach to each switch yoke used on 277 VAC, a 1" diameter red tag reading Caution - 277 VAC. Tag shall not be metal or metal edged. |
| G. | Cover Plates |
| Provide commercial quality. Color and finish for plates, switches and receptacles shall be specified as selected by the architect (coordinate with the architect). |
| H. | Painting |
| See division 9. |
| I. | Electrical Equipment Identification |
| 1. | Identify all switchboard and separately-mounted circuit breakers, panelboards, motor starters, disconnect switches, relays and all apparatus used for the operation or control of power circuits, appliances or equipment, by means of descriptive engraved nameplates. Specify plates of 3/32" thick laminated black bakelite with white core engraved to core to provide white lettering on a black background and a permanent method of securing to equipment. Use red nameplate on all emergency equipment. Do not use adhesives for this purpose. |
| 2. | Identify all motors and other pieces of electrically-operated apparatus with 3/4" minimum height painted stencil lettering. Color to contrast with background color. |
| 3. | Identify lighting and receptacle panel circuit breakers by permanently fixed numbers and a type written directory mounted under clear plastic with a 6" x 8" metal frame on inside of cabinet door. |
| 4. | Identify all telephone and signal outlets and remote control switches by engraving descriptive markings on flush plates. |
| 5. | Submit nameplates and lettering to the architect before installing. |
| J. | Alarms Identification |
| 1. | Whenever a warning system with visible or audible alarm is installed for any reason, a sign containing the following information shall be posted below it: (See this division for fire alarms.) |
| a. | Cause of the alarm. |
| b. | Instructions or procedure to follow. |
| c. | Person(s) to contact. This will be provided by Planning, Design and Construction (CP). |
| d. | Telephone number(s). This will be provided by Planning, Design and Construction (CP). |
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