RACEWAYS

RACEWAYS
PART 1 - GENERAL
1.01 RELATED DOCUMENTS:
A. Drawings and general provisions of Contract, including General and
Supplementary Conditions and Division 1 Specification Sections, apply to this
Section.
B. Requirements of the following Division 16 Sections apply to this Section:
1. "Basic Electrical Materials and Methods".
1.02 SUMMARY:
A. This Section includes raceways for electrical wiring. Types of raceways in this
section include the following:
1. Galvanized electrical metric tubing (EMT)
2. Intermediate metal conduit (IMC)
3. Rigid heavy gauge steel conduit.
4. Flexible steel conduit.
5. Liquid-tight flexible steel conduit.
6. Rigid heavy gauge PVC conduit.
7. Flexible PVC conduit.
8. Wiring and cable trunking.
B. Related Sections: The following Division 16 Sections contain requirements
that relate to this Section:
1. "Cable Trays" for cable tray type raceways".
2. "Wires and Cables" for other wiring methods.
3. "Supporting Devices" for raceway.
4. "Electrical Cabinets, Boxes and Fittings" .
In addition to Division 11 "EQU
IPMENT", Division 13 "SECURITY
SYSTEM" Section, and Division 15 "ELECTRICAL REQUIREMENTS FOR
MECHANICAL WORKS" Section.
1.03 SUBMITTALS:
A. General: Submit the following in accordance with Conditions of Contract and
Division 1 Specification Sections.
B. Product Data: submit manufacturer's technical product data, including
specifications and installation instructions for each type of raceway system and
box required. Include data substantiating that materials comply with
requirements.
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C. Samples: 15 cm long sample of each type and size of surface raceway with
required finish.
D. Installation Instructions: manufacturer's written installation instructions for
wireway, surface raceway, and non metallic raceway products.
E. Shop Drawings: submit dimensioned drawings of raceway systems showing
layout of raceways and fittings, spatial relationships to associated equipment,
and adjoining raceways, if any. Show connections to electrical power panels
and feeders. Provide the following:
1. exact routing of conduits, trunking etc. with indication of boxes,
accessories and expansion joints, size and type of conduits and boxes.
2. typical assembly details of installation of trunking, trays etc.
3. construction details of pull boxes
4. typical installation details including connection of conduits to metal
enclosure, connection of flexible conduits, weatherproof installations
outdoors etc. and earthing connections.
F. Maintenance Data: submit maintenance data and parts lists for each type of
raceway system installed, including furnished specialities and accessories.
Include this data, product data, and shop drawings in maintenance manual; in
accordance with requirements of Division 1.
1.04 QUALITY ASSURANCE:
A. Manufacturers: firms regularly engaged in manufacture of raceway systems
of types and sizes required, whose products have been in satisfactory use in
similar service for not less than 5 years.
B. Codes and Standards:
1. Codes and Standards: comply with local national code, Standards and
Regulations having jurisdiction in host country or as recommended by
the Authority for the project .
2. IEC Compliance: comply with applicable IEC requirements pertaining
to raceways where not in contradiction with above.
3. BS Compliance: comply with applicable requirements of BS
specifications pertaining to construction of raceway systems unless
otherwise specified/approved.
1.05 SEQUENCING AND SCHEDULING:
A. Coordinate with other work, including metal and concrete deck installations, as
necessary to interface installation of electrical raceways and components with
other Work.
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PART 2 - PRODUCTS
2.01 MANUFACTURERS:
A. Available Manufacturers: subject to compliance with requirements,
specifications, drawings, regulations and recommended manufacturers list.
2.02 STEEL CONDUIT AND TUBING:
A. General: provide steel conduit and fittings of types, and sizes as required for
each service indicated. Provide proper selection to fulfill wiring requirements in
compliance with applicable portions of Codes and Standards for raceways and
the applicable Regulations.
B. Rigid Heavy Gauge Steel Conduit: heavy gauge drawn and welded steel,
threaded at both ends, to BS 4568 Part 1 and BS 31 Class B (threaded), with
class 4 protection for rigid steel conduit, zinc coated inside and outside by hotdip
process.
1. Fittings Generally: threaded type, galvanized or cadmium plated
malleable cast iron. Fittings used in corrosive atmospheres are to be
specially treated. Fittings and components are to comply with BS 4568
Part 2 and BS 31.
2. Locknuts: for securing conduit to metal enclosure are to be heavy
hexagonal or castellated pattern, for fastening.
3. Bushings: for terminating conduits are to be smooth rounded brass rings.
4. Miscellaneous Fittings: including reducers, chase nipples, three piece
unions, split couplings and plugs are to be standard fittings designed and
manufactured for the particular application.
C. Intermediate Metal Conduit (IMC): rigid high grade mild strip welded street,
hot dip galvanised over the entire length including factory made threads after
cutting, with organic corrosion resistant polymer inside coating, to UL 1242
and ANSI C 80.6, complete with factory made bends where site bending is not
possible, factory made and threaded fittings and connectors and terminations
with rigid coupling, concrete tight where required, and with red lead coated
threads where site cut.
D. Electrical Metric tubing (EMT): rigid high grade mild strip steel hot dip
galvanised over the entire length with organic corrosion resistant polymer
inside coating to UL 797 and ANSI C 80.3, complete with factory made bends
where site bending is not possible and joints terminations made with steel
couplers and set screw type steel connectors with insulated throats, concrete
tight where required in concrete slab installations.
E. Flexible Steel Conduit: cold rolled and annealed, non-threaded type, formed
from continuous length of helically wound and interlocked strip steel, with
fused zinc coating on inside and outside, and to BS 731.
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1. Fittings Generally: threadless, hinged clamp type, galvanized or cadmium
plated malleable cast iron. Fittings used in corrosive atmospheres are to be
specially treated.
2. Straight Connectors: one piece body, female end having hinged clamp and
deep slotted machine screws for securing to conduit, male end having thread
and locknut.
3. Angle Connectors: 45 or 90 degrees terminal connectors as specified for
straight connectors, except that body is to be two-piece with removable
upper section.
F. Liquid-Tight Flexible Metal Conduit: constructed of single strip, flexible,
continuous, interlocked, and double-wrapped steel; galvanised inside and
outside; coated with liquid-tight jacket of flexible polyvinyl chloride (PVC).
G. Steel Conduit Accessories:
1. Sleeves Through Outside Walls: cast iron, with end and intermediate
integral flanges, and internal diameter larger than diameter of throughconduit.
Length is to correspond to wall thickness. Space between sleeve
and conduit is to be packed with oakum to within 50 mm of both faces of
wall, remainder of sleeve packed with plastic compound or lead, held in
place by heavy escutcheon plates bolted at both ends to flanged ends of
sleeve. Alternatively, sleeves are to be equal to O.Z/Gedney, Type WSK
and approved, with cable or conduit bolted pressure sealing components.
2. Supports and Hangers: galvanised malleable cast iron straps or structural
steel sections with hot dip galvanised bolts and nuts. Refer to Section
"Supporting Devices" for other requirements.
3. Expansion Joint for Embedded Steel Conduits: watertight, flexible conduit
with end fittings to receive fixed conduits. Length is to allow movement
within range of joint and is not to be less than 20 times diameter of conduit.
Conduit is to be covered with thick rubber tubing with 5 mm minimum gap
all around tube. Bonding jumper with earth clamp is to be electrically
connected both sides of joint. Fitting is to be equal to O.Z/Gedney, Type
DX and approved.
4. Expansion Joint for Exposed Steel Conduits: sleeve with fittings to permit
telescoping of one conduit into sleeve. Movable conduit is to be fitted with
water-tight bushing. Joint is to be weatherproof, of galvanised malleable
iron or steel. Bonding jumper with earth clamp is to electrically connect
both sides of joint. Expansion fitting is to be equal to O.Z/Gedney, Type
DXX and approved.
2.03 PVC CONDUIT:
A. General: provide PVC conduit and fittings of types and sizes indicated for
each service . Where types and sizes are not indicated, provide proper selection
to fulfil wiring requirements, which comply with provisions of applicable codes
and standards.
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B. Rigid Heavy Gauge PVC Conduit: rigid polyvinyl chloride with high impact
and high temperature resistance, flame retardant, non-hygroscopic and nonporous,
conforming to IEC 423, 614-1 and 614-2, BS 4607 and BS 6099, DIN
49026 or other equal and approved standards .
1. Fittings Generally: unbreakable, non-inflammable, self extinguishing,
heavy moulded plastic. Expansion couplings are to be telescoping double
tube type, with at least two inner water-tight neoprene rings.
2. Assembly: conduits, boxes and accessories, are to be assembled by
cementing, using manufacturer's recommended products and appropriate
connectors or spouts. Where no spouts are available use smooth bore male
PVC bushes and sockets.
C. Flexible PVC Conduit: flame retardant, heat resistant, non-hygroscopic PVC,
high resistance to impact, ribbed on circumference for flexibility.
D. Under Ground Rigid Heavy Gauge UPVC Ducts: rigid unplasticized polyvinyl
chloride to BS 3506, class B where embedded in concrete duct bands and Class
C where directly buried in ground.
2.04 WIRING AND CABLE TRUNKING:
A. General: wiring and cable trunking is to include wire way base, clip-on
covers, couplings, end plates, wall flanges, panel to trunking rubber
grommets, elbows, tees, adapter plates and necessary hangers, supports and
accessories. Sizes shall be as required to accommodate number of
conductors permitted by the applicable standards and/or as shown on the
Drawings.
B. Steel Trunking: construct steel trunking to BS 4678 Part 1, galvanized sheet
steel, minimum 1.5 mm thick, protected internally and externally with
corrosion resistant finish such as zinc or cadmium with top coat of enamel.
PART 3 - EXECUTION
3.01 INSPECTION:
A. Examine areas and conditions under which raceways are to be installed, and
substrate which will support raceways. Do not proceed with work until
unsatisfactory conditions have been corrected in manner acceptable to Engineer.
3.02 INSTALLATION OF RACEWAYS:
A. General: install raceways as indicated and shown on construction/shop
drawings, in accordance with manufacturer's written installation instructions
where applicable and in compliance with applicable Code, Regulations and
Standards. Install plumb and level, and maintain required clearances.
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B. Co-ordinate With Other Work: including wires/cables, boxes, and panel work,
as necessary to interface installation of electrical raceways and components
with other work.
C. Use: unless otherwise specifically indicated all lighting and power circuits,
communications, signal and low current systems wiring are to be drawn inside
conduits or wireways up to the various electric power consuming equipment as
shown on the Drawings. Separate conduit and wireway installations are to be
used for HV cables, normal lighting and power circuits, emergency lighting
and power circuits, telephone, other communication, signal and low current
systems wiring.
D. Boxes: junction, pull and splice boxes of ample capacity are to be provided as
indicated or required. Boxes are to remain permanently accessible.
E. Tools and accessories for forming and installing conduit and wireway systems
are to be purpose made for the particular application and used in accordance
with manufacturers' instructions.
F. Fixing: conduits and wireway installations are to be concealed as much as
possible.
G. Sizes of conduits and wireways, not shown on the Drawings, are to be selected
in accordance with the Regulations and in relation to the number and size of
conductors. Minimum size of conduit for all applications is to be 20 mm
diameter, unless otherwise shown on the Drawings.
3.03 INSTALLATION OF CONDUITS:
A. General: install concealed conduits in new construction work, in walls,
underfloor, in slabs, or above hung ceilings. Follow indications on drawings
1. Mechanically Fasten: conduits and wireways are to be effectively joined
together and connected to electrical boxes, fittings and cabinets to provide
firm mechanical assembly. Earthing jumpers are to be installed on steel
conduits where required to ensure effective electrical continuity
irrespective of whether a separate protective earth conductor is required or
not.
2. Avoid use of dissimilar metals throughout system to eliminate possibility
of electrolysis. Where dissimilar metals are in contact, coat surfaces with
corrosion inhibiting compound before assembling and use earth bonding
jumper for electrical continuity.
3. Install miscellaneous fittings such as reducers, chase nipples, 3-piece
unions, split couplings, and plugs that have been specifically designed and
manufactured for their particular application. Install expansion fittings in
straight runs of raceways every 30 meters, or wherever structural expansion
joints are crossed.
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4. Set conduit and boxes for connection to units only after receiving final
approved drawings with dimensions and after checking location with other
trades.
5. Provide 2mm diameter galvanised pull wire fastened by wood blocks or
threaded iron plugs at ends in all empty conduits. Test Conduits installed,
but left empty, with ball mandrel. Clear or replace any conduit, which
rejects ball mandrel. Restore conduit and surrounding surfaces to original
condition.
6. Sleeves: obtain approval for positioning sleeves where conduits pass
through reinforced concrete. Additional openings may be allowed in
finished slabs but are to be drilled and not broken. Fix sleeves rigidly to
maintain position and alignment during construction work.
7. Waterproof Construction: conduits are not to cross waterproof
construction unless permitted by the Engineer. Specially designed and
approved fittings are to be used.
8. Make good all holes for conduit sleeves passing through walls, floors and
ceilings with fire-resisting cement or approved material to full thickness.
9. Bends: conduit runs between outlet and outlet, fitting and fitting or outlet
and fitting are not to contain more than the equivalent of 2 quarter bends
(180 degree total).
10. Draining: arrange conduits so that condensed moisture can drain to
screwed plug at lowest point.
11. Conduit and fittings installed outdoors are to be watertight and highly
resistant to corrosion. Use appropriate fittings, threaded and Hubbell
boxes, gaskets with screw on covers and the like.
12. Standard elbows are to be used for conduit sizes over 40 mm. For smaller
sizes, field bends may be used provided no damage occurs to conduit.
13. Tags: fit to conduits entering or leaving floors, walls or ceilings for
identification of conduit and circuits. Tags are also to be placed at suitable
intervals throughout the system. Refer to Section "Identification".
14. Damage to protective coating of conduits is to be repaired to original
degree of protection.
15. Outdoor Mounted Steel Conduit: apply anti-corrosion coating of zincchromate
based paint and two weather resistant finish coats of enamel, of
approved colour, or other equal and approved coating.
16. Cut conduits straight, properly ream, and cut threads for heavy wall conduit
deep and clean.
17. Field-bend conduit with benders designed for purpose so as not to distort
nor vary internal diameter.
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18. Fasten conduit terminations to boxes or enclosures by appropriate methods
and terminate with bushing where conduits do not terminate in hubs.
19. Conduits are not to cross pipe shafts, or ventilating duct and openings.
20. Keep conduits a minimum distance of 150 mm from parallel runs of flues,
hot water pipes or other sources of heat. Wherever possible, install
horizontal raceway runs above water and steam piping.
21. Support riser conduit at each floor level with clamp hangers or other
methods as described in Section "Supporting Systems".
22. Use of running threads at conduit joints and terminations is prohibited.
Where required, use 3-piece union or split coupling.
23. Complete installation of electrical raceway system, including boxes,
enclosures etc., before starting installation of cables/wires within raceway
system. Cap empty conduits until wiring is in progress, using standard
manufacturer's fittings.
24. Space occupation factor in conduits shall never exceed Code/Regulations
requirements except if approved under special cases.
B. Conduit Application: Provide rigid heavy gauge galvanised steel, intermediate
metal conduit (IMC), electrical metallic tubing (EMT), heavy gauge PVC
conduit or other types of conduit in accordance with the following:-
1. Use rigid heavy gauge galvanised steel or IMC conduit for all exposed
installations in mechanical equipment, generator rooms (except exposed
lighting & small power circuit conduits in these rooms which are to be
EMT type), for all exposed outdoor installations, for all feeder/subfeeder
runs in non-accessible false ceiling areas, for swimming pool and fountain
installations according to NEC, for embedded and exposed installations in
hazardous explosive areas (e.g. paint shops) and as shown on the Drawings
or specified elsewhere.
2. Use EMT for all exposed installations in elevator machine rooms and
shafts, electrical equipment rooms, environmental air ducts or plenums or
false ceiling areas where used as air plenums, for all exposed or above false
ceiling installations of security, parking, kitchen, laundry, solid waste, fire
alarm wiring circuits, and as shown on the Drawings or specified
elsewhere.
3. Use flexible conduit, metallic or non-metallic consistent with respective
fixed conduit installation, in movable partitions and from outlet boxes to
recessed lighting fixtures over suspended/false ceilings , and final
minimum Regulation/Code length of connection to motors, or control items
subject to movement or vibration, and through cellular precast concrete
panels where required.
4. Use liquid-tight flexible steel conduit where subjected to one or more of
the following conditions:
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- Exterior location.
- Moist or humid atmosphere where condensate can be expected to
accumulate.
- Corrosive atmosphere.
- Subjected to water spray or dripping oil, water or grease.
5. Use rigid heavy gauge PVC conduit for embedded (in wall or slab), underfloor,
consealed (in dry walls) and above false ceiling installations for
lighting, power circuits and low current & communication circuits, unless
otherwise indicated or specified.
C. Underground Ducts: Use heavy gauge UPVC or ducts. Draw up coupling and
conduit sufficiently tight to ensure water tightness. Use manufacturer's
recommended cement and procedures.
1. For underground installations, unless otherwise indicated on the drawings
install ducts at a minimum of 550 mm below finished grade for low voltage
Use appropriate standard plastic spacers- for proper spacing of ducts.
2. End of ducts in cable manholes, handholes walls or trenches are to be
neatly cut and reamed and terminated with appropriate bell-month bushing
in concrete wall or set behind chamfered precast concrete duct and blocks.
3. Ends of ducts, whether active or spare, at entry into building or manhole
are to be completely sealed with approved plug and sealing material to
prevent entry of rodents, gas, water, and vapour.
4. Provide 3 mm galvanised steel wire inside empty ducts, for future pulling
of cables, extended 1 m beyond duct banks at both ends and security fixed
to the sealing plugs of the ducts.
5. Provide 1% slope to duct banks for draining to exterior manhole, handhole
or other location as instructed.
D. Conduits in Concrete Slabs:
1. Place conduits in middle third of slab thickness where practical, between
bottom reinforcing steel and top reinforcing steel, leaving at least 25 mm
concrete cover.
2. Place conduits either parallel, or at right angles, to main reinforcing steel
and fasten to reinforcing steel by positive wire fasteners at the proper
distance from the concrete face. Place conduits larger than 25 mm parallel
with or at right angles to reinforcement, closest possible to slab supports.
3. Separate conduits by not less than one diameter of the larger conduit of two
parallel conduits in a group, to ensure proper concrete bond.
4. Conduits crossing in slab must be reviewed for proper cover by the
Engineer.
5. Embedded conduit diameter is not to exceed 1/3 of slab thickness. Special
cases shall be reviewed by the Engineer.
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6. Bends of embedded conduits into partitions and stub-ups shall rise a
minimum of 100mm above finished floor. Arrange so that the curved
portion of bends is not visible above finished slab. Protect all stubs against
damage.
7. Stub-up Connections: extend conduits through concrete floor for
connection to free-standing equipment with an adjustable top or coupling
threaded inside for plugs and set flush with finished floor. Extend
conductors to equipment with rigid steel conduit. Flexible metal conduit
may be used 100 mm above the floor. Where equipment connections are
not made under this contract install screwdriver-operated threaded flush
plugs, flush with floor.
E. Install conduits so as not to damage or run through structural members. Avoid
horizontal or cross runs in building partitions or side walls.
F. Exposed Conduits:
1. Install exposed conduits and extensions from concealed conduit systems
neatly, parallel with, or at right angles to nearby surfaces or structural
members and follow the surface contours as much as practicable.
2. Install exposed conduit work so as not to interfere with ceiling inserts,
lights or ventilation ducts or outlets.
3. Support exposed conduits by use of galvanised wall brackets, ceiling
trapeze or pipe strap hangers. Support conduits on each side of bends and
on linear spacing not to exceed 1.50m. Refer to Section "Supporting
Devices".
4. Run conduits exposed for outlets on waterproof walls . Set anchors for
supporting conduit on waterproof wall in waterproof cement.
5. Above requirements for exposed conduits also apply to conduits installed
in space above hung ceilings.
G. Heavy Gauge PVC Conduits:
1. Make cemented joints in accordance with recommendations of
manufacturer. Use manufacturers standard fittings, couplings, bends,
terminations and cementing compound.
2. Install PVC conduits in accordance with approved applicable standards and
methods .
H. Steel Conduit Fittings:
1. Fit ridged lockouts inside and outside of surface of metal enclosure to
which conduit is fixed for proper fastening.
2. Bushings for terminating conduits smaller than 32mm are to have flared
bottom and ribbed sides, with smooth upper edges to prevent injury to
cable insulation.
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3. Install insulated type bushings for terminating conduits 32mm and larger.
Bushings are to have flared bottom and ribbed sides, upper edge to have
phenolic insulating ring moulded into bushing.
4. Bushing of standard or insulated type to have screw type grounding
terminal.
5. Miscellaneous fittings such as reducers, chase nipples, 3-piece unions, split
couplings, and plugs to be specifically designed for their particular
application.
3.04 INSTALLATION OF RACEWAYS AND WIREWAYS, OTHER THAN
CONDUITS:
A. General: mechanically assemble metal enclosures, and raceways for conductors
to form continuous electrical conductor, and connect to electrical boxes, fittings
and cabinets as to provide effective electrical continuity and rigid mechanical
assembly.
B. Avoid use of dissimilar metals throughout system to eliminate possibility of
electrolysis. Where dissimilar metals are in contact, coat all surfaces with
corrosion inhibiting compound before assembling.
C. Install expansion fittings in all raceways wherever structural expansion joints
are crossed.
D. Make changes in direction of raceway run with purpose made fittings,
supplied by raceway manufacturer. No field bends of raceway sections will be
permitted.
E. Properly support and anchor raceways for their entire length by structural
materials. Raceways are not to span any space unsupported.
F. Use boxes as supplied by raceway manufacturer wherever junction, pull or
device boxes are required. Standard electrical "handy" boxes, etc. shall not be
permitted for use with surface raceway installations.
END OF SECTION 16110