Download section 16450 - electrical wiring

SECTION 16450 - ELECTRICAL WIRING
PART 1 - GENERAL
1.01
RELATED DOCUMENTS
The General Provisions of the Contract, including General, Supplementary and Special
Conditions, apply to the work specified in this Section.
1.02
GENERAL INSTALLATION REQUIREMENTS
A.
All electrical work dealing with electrical circuits or power requirements of 110 volts or higher
shall be performed by a licensed journeyman electrician supervised by an on site master
electrician.
B.
All cables not installed in conduit shall be plenum rated.
C.
All conductors and cable shall be properly labeled at both ends and at any intermediate splice.
D.
All low voltage cables shall be installed in continuous length without splice.
E.
All plenum rated cables shall be supported from and near structure with nylon straps or D-rings.
Do not weave through joists for support.
F.
Install conduit sleeves for all masonry penetrations of plenum rated cables.
G.
In areas of remodeling, remove all conduit and wire that is not to be reused.
H.
Provide grounding bushings for all connections at concentric and eccentric knockouts, and where
reducing washers are used.
I.
All junction boxes and other devices above ceiling that may require maintenance shall be located
within 18” of the ceiling.
J.
All exterior junction boxes in the ground shall be concrete type with traffic rated tops.
K.
All junction and pull boxes shall be marked noting electrical circuits contained. Additionally,
boxes containing emergency or exit circuits shall have housing painted red. Boxes containing
normal high voltage circuits shall have housing painted yellow. Boxes containing normal low
voltage circuits shall have housing painted blue. Do not paint the covers.
PART 2 - MATERIALS AND METHODS
2.01
A.
RACEWAY SYSTEMS
REQUIRED: Complete raceway systems for all wiring. This includes, but is not limited to
feeders, branch circuit wiring, temperature controls wiring, data cabling, video cabling, sound
system wiring and fire alarm system wiring. Generally auxiliary system and controls wiring is
plenum rated so conduit system would consist of junction boxes and conduit in walls or above
inaccessible ceilings only. Control and interlock wiring shall be provided under the Mechanical
Section.
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B.
RACEWAY CAPACITY: It shall be the Contractor's responsibility to determine the correct sizes
of all types of raceway, to be installed, as instructed in the NEC and all applicable Codes. Runs
of underground conduit longer than 80 feet shall be one size larger than NEC requirement, 4"
maximum.
C.
INSTALLATION:
1.
LOCATION: Conceal all raceway systems in ceilings, walls and floors, except feeders
serving equipment in mechanical and electrical equipment rooms, and in such other areas
as indicated where conduit may be exposed. Keep at least 8" away from any heat
producing items. Do not install conduit below grade or in floor slabs unless there is no other
way to conceal conduit. Equipment feeders in mechanical rooms or mechanical yards shall
be run above grade. Major feeders from switchboard to distribution panels containing 4/0 or
larger wire may be run underground. Do not install conduit on roof unless specifically
shown to be on the roof or authorized in writing by the Engineer. All junction and pull boxes
above accessible ceilings shall be mounted so that the access panel is no higher than 18”
above the ceiling.
2.
ROUTING:
Conduit shall be installed parallel to building coordinates, except for
underground feeders from panel to panel may be installed in the most direct manner. Install
all horizontal conduit at structure unless mounted to a wall.
3.
EXPOSED RACEWAY: Run parallel to walls, ceiling or structural members, in a manner to
present a neat appearance. Before installation, explain to the Inspector the proposed
method of routing and obtain his approval. Hold all horizontal conduit at ceiling or structure,
unless mounted on wall.
4.
SUPPORT: Provide adequate and sturdy support for all parts of raceway system. Conduit
concealed in walls or slabs may be supported with wire hangers, provided they are of heavy
gage and spaced to give adequate strength. Exposed conduit must be supported with
materials specifically made for this purpose; do not use wire hangers. Do not attach any
parts of raceway system to air conditioning ducts or ceiling systems. Wiring above ceiling
without conduit shall be supported from structure or wall with J hooks or other manufactured
devices designed for this service. Unless described by detail on the drawings, provide
Tolco Pipe Pier Supports four foot on center to support conduit on the roof. Select for
proper weight loading.
5.
CONTINUITY: Make all joints and connections in a manner which will insure mechanical
strength and electrical continuity. Use double locknuts and insulated bushings for rigid
conduit, and insulated type connectors for EMT conduit 1” and larger for connections to
boxes. Use insulated grounding bushings wherever connection is subject to vibration or
moisture, such as near mechanical equipment, when internal ground wire is installed, and
when concentric or eccentric knockouts are encountered, as well as where reducing
washers are used.
6.
PULL BOX LOCATIONS: As required by the National Electrical Code.
7.
EXPANSION FITTINGS: Install O. Z. or equal expansion fitting in each run of conduit which
crosses building expansion joint, and in all runs longer than 200 feet.
8.
CORROSION PROTECTION: For all non-coated metal raceway in contact with concrete or
mortar, tape with 3M corrosion protective tape, or equal. Tape shall extend for
approximately 6" before entering and after exiting concrete. Conduit through slabs at grade
shall be PVC coated rigid galvanized steel.
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9.
PULL WIRE: Install nylon pull cord in all empty electrical power raceway systems.
10. OPENINGS: Keep all raceway openings closed in a manner to prevent entry of moisture
and foreign materials until conductors are installed.
11. FIRE PROOFING: All power and telephone raceway components passing through or
installed within U. L. fire rated walls, ceiling or floor structures shall be fireproofed in the
manner prescribed by the U. L. Fire Resistive Index and local building codes. All
penetrations shall be fireproofed with 3M Fire Barrier CP25WB caulk, moldable putty or FS195 wrap/strip installed per the manufacturer's recommendations.
12. SEALING: All conduit, junction box, outlet box and other penetrations of the building
envelop shall be sealed with non-hardening caulking or other non-hardening material as
required by the International Energy Conservation Code.
D.
2.02
A.
B.
MANUFACTURERS: All components of raceway systems must be made in U.S.A. and bear U.
L. label.
CONDUIT
CONDUIT TYPES
1.
RIGID GALVANIZED STEEL – Threaded fittings
2.
PVC COATED RIGID GALVANIZED STEEL - Plasti-Bond REDH2OT with ETL Verified
PVC-001 label or equal with ETL label. Provide Plasti-Bond coated couplings, fittings and
pulling elbows.
3.
PVC CONDUIT – Schedule 40
4.
EMT – Steel conduit with diecast or steel watertight fittings
5.
FLEXIBLE METAL CONDUIT – Greenfield, galvanized steel conduit for field installation of
conductors
6.
LIQUID TIGHT FLEXIBLE METAL CONDUIT – SealTite Type UA galvanized steel conduit
with PVC waterproof coating for field installation of conductors
7.
MC CABLE – Flexible steel conduit with factory installed, stranded, color coded copper
conductors, green insulated ground wire and polypropylene sheath/tape. Conduit exterior
shall be color coded for contained conductors. AFC MC Tuff
8.
SURFACE RACEWAY – Wiremold steel raceway, ivory finished and mechanically
connected to walls or casework. Type based on application.
9.
CABLE TRAYS – Cooper B-Line 36 Series aluminum, ladder type cable tray with 9” rung
spacing. Width based on application. Support per manufacturer’s recommendations.
TYPE OF CONDUIT FOR VARIOUS LOCATIONS:
1.
UNDERGROUND: Rigid galvanized steel or Schedule 40 PVC. Conduit in contact with
concrete shall be PVC coated, rigid galvanized steel. Install PVC coated, rigid galvanized
steel, long radius elbows where conduit turns up to grade including straight length section to
a minimum of 6” above concrete or to panel connection. Encase underground conduit not
under building slab in a 3" red concrete envelope located a minimum of 24" below finished
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grade to top of envelope (48" if above 600 volts). Where more than one conduit is installed
in the same trench, provide manufactured conduit support spacers to organize conduit and
ensure proper concrete encasement. Notify Inspector for inspection of duct bank at least 24
hours prior to concrete placement. Conduit below building slab or conduit for telephone,
data, etc. do not require concrete encasement. Conduit 1” and smaller under the building
slab may be run just under the concrete. Larger conduit shall be 24” below finished floor.
2.
IN POURED CONCRETE WALLS: PVC coated, rigid galvanized steel or Schedule 80
PVC. Install PVC coated rigid steel fittings on PVC conduit prior to conduit exiting concrete.
3.
IN MASONRY WALLS: Galvanized steel EMT with steel, watertight fittings.
4.
EXPOSED OUTSIDE OF BUILDING: Rigid galvanized steel. For conduit in mechanical
courtyard within 50 feet of a cooling tower provide PVC coated, rigid galvanized steel
conduit and fittings.
5.
INSIDE OF BUILDING IN CEILING CAVITIES, IN EXPOSED FLOOR OR ROOF
STRUCTURE AREAS, OR IN DRY WALL TYPE CONSTRUCTION: Galvanized steel EMT
or rigid galvanized steel.
6.
EXPOSED ON EXISTING MASONRY OR PLASTER WALLS IN FINISHED AREAS: Do
not install surface mounted conduit in finished areas.
7.
IN CONCRETE SLABS: Do not install conduit in concrete slabs.
8.
FLEXIBLE METAL CONDUIT CONNECTIONS: Use only for connection to lights, motors
and transformers from rigid conduit system. Do not loop flexible conduit between light
fixtures or receptacles. Provide liquid tight construction and fittings in wet, damp or outside
areas. Connections to mechanical equipment in main mechanical or boiler room, and
kitchen equipment shall be in liquid tight. Do not install inside an air handling unit room.
Minimum length shall be 18”. Minimum length shall be 18”. Maximum length shall be three
feet except light fixture whips may be up to six feet.
9.
LIGHT FIXTURE WHIPS: MC cable not to exceed six feet in length.
C.
MINIMUM CONDUIT SIZE: 1/2", all homeruns shall be 3/4” minimum.
D.
FITTINGS:
E.
1.
RIGID CONDUIT: All rigid galvanized steel conduit shall have threaded fittings with
insulated bushings.
2.
EMT CONDUIT: Provide insulated bushings for all EMT conduit 1" or larger or housing #6
or larger wires.
3.
GROUNDING: Provide fitting with grounding lug where conduit attaches to a painted box
(disconnect switch, starter, transformer case, etc), conduit attaches to a box through a
knockout which has an associated larger knockout or a reducing washer is used, or conduit
contains a feeder from switchgear to switchgear or between switchgear and transformer.
4.
TELEPHONE AND DATA CONDUIT: Provide protective bushing on the end of telephone,
data, sound system or other conduit stubbed into the ceiling cavity.
SPARE CONDUIT: Provide five empty 1” conduit from all recessed electrical panels to above the
nearest accessible ceiling.
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F.
2.03
LOW VOLTAGE CONDUCTORS: Low voltage conductors may be run in accessible ceilings
without conduit. Provide conduit sleeve with protective end fittings through all walls and floors
where raceway system is not installed. All exposed conductors shall be in conduit. All splices
shall be in supported junction boxes. Low voltage conductors installed without conduit shall be
independently supported on ring hangers, and plenum rated. Low voltage conductors for audio
and data wiring shall be stranded unless otherwise recommended by the manufacturer.
PULL BOXES
A.
REQUIRED: Pull boxes, junction boxes, wiring troughs and cabinets wherever required for
proper installation of various electrical systems.
B.
CONSTRUCTION: Made of code gage steel with sides formed and welded, screw covers unless
shown to have hinged doors. Hinged doors to be same as furnished on panel boards, with same
locking device. Knockouts shall be factory made or formed in field with a cutting tool which will
provide a clean, symmetrically cut hole. Do not gang boxes or use extension rings to increase
capacity. Boxes outside shall be steel NEMA 3 Type.
2.04
OUTLET BOXES
A.
REQUIRED: For all switches, light fixtures, receptacles and the various other outlets shown.
B.
CONSTRUCTION: Galvanized steel, one piece construction, in all cases suitable for intended
use. Provide "gang" boxes where devices are shown grouped. Use hot dipped galvanized cast
iron for floors or exterior locations. Boxes outside shall be steel NEMA 3 Type.
C.
TYPES FOR VARIOUS LOCATION:
D.
1.
CEILINGS: 4" square, 2-1/8" deep.
2.
DRY WALLS: 4" square, 2-1/8" deep standard galvanized switch box. Provide shallow
boxes where necessary. Provide tab to align box with studs.
3.
MASONRY WALLS:
Galvanized switch boxes designed especially for masonry
installations. Depths of boxes must be properly coordinated for each specific installation.
Box shall be installed within 1/8” of surface of block.
4.
FLOOR: Watertight, adjustable, cast iron.
5.
SURFACE MOUNTED: Boxes surface mounted on walls or floor shall be Bell, cast
aluminum box with appropriate plate and threaded hubs.
6.
BACK-TO-BACK OUTLETS: Outlets shown back-to-back on the drawings are to be
installed with a minimum of 6" of lateral separation between outlets for minimum sound
transmission. "Through-the-wall" type boxes are not permitted.
7.
SPECIAL: Boxes for VGA outlets shall have 1.25” knockouts/lugs.
MOUNTING PLATES: Boxes mounted in drywall construction shall have extension plates
matched to wall thickness so the box can be mounted flush with the metal stud and the wiring
device mounts flush with the wall.
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2.05
CONDUCTORS
A.
REQUIRED: A complete system of conductors in all raceway systems except where shown
otherwise. No conductors are to be installed in telephone conduit. Emergency or exit circuitry
shall be installed in a separate raceway system.
B.
BUILDING WIRE: 600 Volt, soft drawn annealed copper, 98% conductivity, continuous from
outlet to outlet. Minimum wire size #12 except remote control wire may be #14. All wire shall be
stranded Type THHN, THW-2 or THWN-2 (wet rated for 90 C). All wires shall be color coded
with same color connected to same ungrounded phase throughout the installation.
C.
BURIED GROUND WIRE: Conductors used to interconnect ground rods of a grounding triad or
supplemental ground loop shall be minimum #2, bare, tinned, solid copper wire. Connect this
wire to rod with short length of same wire, thermo-welded to loop and rod.
D.
MANUFACTURERS: Collier, General Cable, General Electric, Simplex, Triangle and Southwire
Co.
E.
CONNECTORS: Make all connections on #10 and smaller wire with Code approved solderless
pressure type insulated connectors; Ideal Wingnut. Solderless lugs must be used for all
terminations.
F.
TEST: After installation of all conductors, and before final acceptance, make such tests as are
required to determine proper functioning of all circuits. Furnish all necessary instruments
required to make such tests and correct any deficiencies found.
2.06
CONNECTIONS TO MOTORS, EQUIPMENT AND DEVICES
A.
POWER WIRING: Make wiring connections to all mechanical, plumbing and other equipment
being installed as a part of this Contract. In addition, make connections to Owner furnished
equipment as shown.
B.
CONTROL WIRING: Control and interlock wiring for HVAC Systems will be provided by the
Mechanical Contractor. Motorized dampers of the same voltage as the associated fan shall be
wired by the electrical contractor when the damper is in close proximity to the fan. Under this
section provide a 20 amp, 120 volt circuit to the control panel in each mechanical room from the
local low voltage panel.
C.
CONNECTIONS TO EQUIPMENT: Make connection to each motor and to each piece of
equipment subject to vibration with not less than 18" nor more than 24” of flexible conduit. All
horizontal runs of conduit (not strapped to walls) must be kept above 7 feet high, with a vertical
drop to equipment. Conduit blocking walk and service space is not acceptable and will require
relocation. Conduit on and adjacent to equipment must be located to allow free access to all
removable panels for equipment service. Wire adjacent to heat producing equipment, such as
boilers and electric heaters, must be of a type approved for this use.
D.
CONNECTIONS TO TRANSFORMERS: Install not less than 18" nor more than 24” of flexible
conduit at each connection to floor mounted transformers.
E.
CONNECTIONS TO RECEPTACLES: All multiple devices on a circuit such as receptacles shall
be back wired with pigtail so device does not provide continuity path.
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2.07
GROUNDING
A.
GENERAL: Permanently and securely ground the mechanical and plumbing equipment and
piping systems, conduit system, panel boards and all other components of the electrical system
installed or connected by the Sub-contractor. Follow NEC and building code requirements.
B.
CIRCUIT GROUNDS: Provide a green ground wire sized per the NEC for every circuit.
C.
EQUIPMENT ENCLOSURES: Make firm ground to raceway system. For equipment connected
with flexible conduit or sealtite shall have the specified ground wire installed inside conduit. Do
not install on the outside of the conduit. Where enclosure is painted, remove paint where ground
lugs are installed.
D.
TRANSFORMERS: Each transformer shall have its enclosure and secondary neutral terminal
(except when a neutral terminal does not exist) bonded to the building steel and local, driven
ground rod.
E.
GROUND WIRE CONDUIT: Conduit containing a service or transformer grounding wire shall be
grounded at each end to the grounding wire. Use conduit grounding fitting at ground rods.
2.08
CIRCUITRY
A.
The intent of the drawings is to indicate schematically the circuitry required.
B.
Do not install more than four current carrying conductors in a conduit except eight #12 may be
installed in 3/4”C. Install a dedicated neutral for each circuit requiring a neutral. Install a green
ground wire for each circuit or group of circuits in one conduit. Segregate data processing
circuits and stage dimming circuits from other types of circuits. Do not install 480/277 volt
conductors in the same conduit with 208/120 volt conductors.
C.
The work performed in grouping conductors in a single raceway shall comply with all applicable
articles in the latest edition of the NEC and Local Codes which shall include, but shall not be
limited to, ampacity de-rating of conductors and maximum capacities of raceways.
2.09
A.
POWER CONDUCTOR COLOR CODING
480/277 VOLT SYSTEM: Conductors shall have insulation of the proper color as listed below:
Phase A
Phase B
Phase C
Neutral
Ground
Isolated Ground
B.
- Brown
- Purple
- Yellow
- Natural Gray
- Green
- Green w/yellow stripe
208Y/120 VOLT SYSTEMS: Conductors shall have insulation of the proper color as listed below:
Phase A
Phase B
Phase C
Neutral
Ground
Isolated Ground
- Black
- Red
- Blue
- White
- Green
- Green w/yellow stripe
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C.
240/120 VOLT DELTA SYSTEMS
Phase A
Phase B
Phase C
Neutral
Ground
Isolated Ground
- Black
- Orange (high leg of delta)
- Blue
- White w/colored stripe
- Green
- Green w/yellow stripe
D.
Contractor may use colored tape marking for size 8 and larger phase and neutral conductors,
and size 4 and larger ground conductors.
E.
Switch legs are to be color coded the same as the un-switched phase, i.e., all wiring from lighting
control panels and contactors shall retain the phase color.
F.
If existing construction has a consistent but different color coding, match existing.
2.10
SPECIAL SYSTEMS CABLE COLOR CODING
A.
Fire Alarm
Red
B.
P/A Communications
White
C.
Misc Low Voltage/Sound
Gray
D.
Data Cabling
Refer to Structured Cabling and Data Racks Specifications
E.
Telephone Cabling
Refer to Telephone Systems Specifications
D.
Other Wiring
Consult with Engineer/Owner. Do not use one of the assigned colors
without authorization.
END OF SECTION
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