Updated Spec Section 33 71 02.pdf

SECTION 33 71 02

UNDERGROUND ELECTRICAL DISTRIBUTION

02/15

(FOR UNDERGROUND TELECOMMUNICATIONS INS TALLATION ONLY

WORK SHALL COMPLY WITH 96CS REQUIREMENTS

CHELCO SHALL INSTALL ELECTRICAL PER CH ELCO STANDARDS)

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this s pecification to the extent referenced. The publications are referred t o within the text by the basic designation only.

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO HB-17 (2002; Errata 2003; Errata 2005, 17th Edition) Standard Specifications for Highway Bridges

AMERICAN CONCRETE INSTITUTE (ACI)

ACI 318M (2014; ERTA 2015) Building Code Requirements for Structural Concrete & Commentary

ACI SP-66 (2004) ACI Detailing Manual

AMERICAN WELDING SOCIETY (AWS)

AWS D1.1/D1.1M (2015; Errata 1 2015; Errata 2 2016) Structural Welding Code - Steel

ASSOCIATION OF EDISON ILLUMINATING COMPANIES (AEIC)

AEIC CS8 (2013) Specification for Extruded Dielectric Shielded Power Cables Rated 5 Through 46 kV

ASTM INTERNATIONAL (ASTM)

ASTM A48/A48M (2003; R 2012) Standard Specification for Gray Iron Castings

ASTM B1 (2013) Standard Specification for Hard-Drawn Copper Wire

ASTM B231/B231M (2012) Standard Specification for Concentric-Lay-Stranded Aluminum 1350 Conductors

ASTM B3 (2013) Standard Specification for Soft or

Annealed Copper Wire

ASTM B400/B400M (2008; E 2013) Standard Specification for Compact Round Concentric-Lay-Stranded Aluminum 1350 Conductor

ASTM B496 (2016) Standard Specification for Compact Round Concentric-Lay-Stranded Copper Conductors

ASTM B609/B609M (2012; E 2015) Standard Specification for Aluminum 1350 Round Wire, Annealed and Intermediate Tempers, for Electrical purposes

ASTM B8 (2011; R 2017) Standard Specification for Concentric-Lay-Stranded Copper Conductors, Hard, Medium-Hard, or Soft

ASTM B800 (2005; R 2011) Standard Specification for 8000 Series Aluminum Alloy Wire for Electrical Purposes-Annealed and Intermediate Tempers

ASTM B801 (2018) Standard Specification for Concentric-Lay-Stranded Conductors of 8000 Series Aluminum Alloy for Subsequent Covering or Insulation

ASTM C139 (2017) Standard Specification for Concrete Masonry Units for Construction of Catch Basins and Manholes

ASTM C309 (2011) Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete

ASTM C32 (2013; R 2017) Standard Specification for Sewer and Manhole Brick (Made from Clay or Shale)

ASTM C478 (2018) Standard Specification for Circular Precast Reinforced Concrete Manhole Sections

ASTM C478M (2018) Standard Specification for Precast Reinforced Concrete Manhole Sections (Metric)

ASTM C857 (2016) Standard Practice for Minimum Structural Design Loading for Underground Precast Concrete Utility Structures

ASTM C990 (2009; R 2014) Standard Specification for Joints for Concrete Pipe, Manholes and Precast Box Sections Using Preformed Flexible Joint Sealants

ASTM C990M (2009; R 2014) Standard Specification for Joints for Concrete Pipe, Manholes and Precast Box Sections Using Preformed Flexible Joint Sealants (Metric)

ASTM F2160 (2016) Standard Specification for Solid Wall High Density Polyethylene (HDPE) Conduit Based on Controlled Outside Diameter (OD)

ASTM F512 (2012; R 2017) Standard Specification for Smooth-Wall Poly (Vinyl Chloride) (PVC) Conduit and Fittings for Underground Installation

INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS ( IEEE)

IEEE 386 (2016) Separable Insulated Connector Systems for Power Distribution Systems Rated 2.5 kV through 35 kV

IEEE 400.2 (2013) Guide for Field Testing of Shielded Power Cable Systems Using Very Low Frequency (VLF)

IEEE 404 (2012) Standard for Extruded and Laminated Dielectric Shielded Cable Joints Rated 2500 V to 500,000 V

IEEE 48 (2009) Standard for Test Procedures and Requirements for Alternating-Current Cable Terminations Used on Shielded Cables Having Laminated Insulation Rated 2.5 kV through 765 kV or Extruded Insulation Rated 2.5 kV through 500 kV

IEEE 495 (2007) Guide for Testing Faulted Circuit Indicators

IEEE 81 (2012) Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials of a Ground System

IEEE C2 (2017; Errata 1-2 2017; INT 1 2017) National Electrical Safety Code

IEEE C37.20.3 (2013) Standard for Metal-Enclosed Interrupter Switchgear

IEEE Stds Dictionary (2009) IEEE Standards Dictionary: Glossary of Terms & Definitions

INSULATED CABLE ENGINEERS ASSOCIATION (ICEA)

ICEA S-94-649 (2013) Standard for Concentric Neutral Cables Rated 5 Through 46 KV

INTERNATIONAL ELECTRICAL TESTING ASSOCIATION (NETA)

NETA ATS (2017; Errata 2017) Standard for Acceptance Testing Specifications for Electrical Power Equipment and Systems

NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)

ANSI C119.1 (2016) Electric Connectors - Sealed Insulated Underground Connector Systems Rated 600 Volts

ANSI/NEMA WC 71/ICEA S-96-659 (2014) Standard for Nonshielded Cables Rated 2001-5000 Volts for use in the Distribution of Electric Energy

NEMA C119.4 (2011) Electric Connectors - Connectors for Use Between Aluminum-to-Aluminum or Aluminum-to-Copper Conductors Designed for Normal Operation at or Below 93 Degrees C and Copper-to-Copper Conductors Designed for Normal Operation at or Below 100 Degrees C

NEMA RN 1 (2005; R 2013) Polyvinyl-Chloride (PVC) Externally Coated Galvanized Rigid Steel Conduit and Intermediate Metal Conduit

NEMA TC 2 (2013) Standard for Electrical Polyvinyl Chloride (PVC) Conduit

NEMA TC 3 (2016) Polyvinyl Chloride (PVC) Fittings for Use With Rigid PVC Conduit and Tubing

NEMA TC 6 & 8 (2013) Standard for Polyvinyl Chloride (PVC) Plastic Utilities Duct for Underground Installations

NEMA TC 7 (2016) Smooth-Wall Coilable Electrical Polyethylene Conduit

NEMA TC 9 (2004) Standard for Fittings for Polyvinyl Chloride (PVC) Plastic Utilities Duct for Underground Installation

NEMA WC 70 (2009) Power Cable Rated 2000 V or Less for the Distribution of Electrical Energy--S95-658

NEMA WC 74/ICEA S-93-639 (2012) 5-46 kV Shielded Power Cable for Use in the Transmission and Distribution of Electric Energy

NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)

NFPA 70 (2017; ERTA 1-2 2017; TIA 17-1; TIA 17-2;

TIA 17-3; TIA 17-4; TIA 17-5; TIA 17-6;

TIA 17-7; TIA 17-8; TIA 17-9; TIA 17-10;

TIA 17-11; TIA 17-12; TIA 17-13; TIA

17-14; TIA 17-15; TIA 17-16; TIA 17-17 )

National Electrical Code

SOCIETY OF CABLE TELECOMMUNICATIONS ENGINEERS (SCTE)

ANSI/SCTE 77 (2013) Specification for Underground Enclosure Integrity

TELECOMMUNICATIONS INDUSTRY ASSOCIATION (TIA)

TIA-758 (2012b) Customer-Owned Outside Plant Telecommunications Infrastructure Standard

U.S. DEPARTMENT OF AGRICULTURE (USDA)

RUS Bull 1751F-644 (2002) Underground Plant Construction

U.S. GENERAL SERVICES ADMINISTRATION (GSA)

CID A-A-60005 (Basic; Notice 2) Frames, Covers, Gratings, Steps, Sump And Catch Basin, Manhole

UNDERWRITERS LABORATORIES (UL)

UL 1072 (2006; Reprint Jun 2013) Medium-Voltage Power Cables

UL 1242 (2006; Reprint Mar 2014) Standard for Electrical Intermediate Metal Conduit -- Steel

UL 44 (2018) UL Standard for Safety Thermoset-Insulated Wires and Cables

UL 467 (2013; Reprint Jun 2017) UL Standard for Safety Grounding and Bonding Equipment

UL 486A-486B (2018) UL Standard for Safety Wire Connectors

UL 510 (2017) UL Standard for Safety Polyvinyl Chloride, Polyethylene and Rubber Insulating Tape

UL 514A (2013; Reprint Aug 2017) UL Standard for Safety Metallic Outlet Boxes

UL 514B (2012; Reprint Nov 2014) Conduit, Tubing and Cable Fittings

UL 6 (2007; Reprint Nov 2014) Electrical Rigid Metal Conduit-Steel

UL 651 (2011; Reprint Nov 2018) UL Standard for

Safety Schedule 40, 80, Type EB and A Rigid PVC Conduit and Fittings

UL 83 (2017) UL Standard for Safety Thermoplastic-Insulated Wires and Cables

UL 854 (2004; Reprint Nov 2014) Standard for Service-Entrance Cables

UL 94 (2013; Reprint Sep 2017) UL Standard for Safety Tests for Flammability of Plastic Materials for Parts in Devices and Appliances

1.2 RELATED REQUIREMENTS

Section 26 08 00 APPARATUS INSPECTION AND TESTING applies to this s ection, with the additions and modifications specified here in.

1.3 DEFINITIONS

a. Unless otherwise specified or indicated, electr ical and electronics terms used in these specifications, and on the draw ings, are as defined in IEEE Stds Dictionary .

b. In the text of this section, the words conduit and duct are used interchangeably and have the same meaning.

1.4 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for inf ormation only. When used, a designation following the "G" designation i dentifies the office that will review the submittal for the Government. Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Precast underground structures ; G

SD-03 Product Data

Precast concrete structures ; G

Sealing Material

Pulling-In Irons

Handhole frames and covers ; G

Composite/fiberglass handholes ; G

Cable supports (racks, arms and insulators); G

SD-06 Test Reports

Field Acceptance Checks and Tests ; G

Cable Installation Plan and Procedure ; G

Six copies of the information described below in 8-1/2 by 11 inch binders having a minimum of three rings from which material may readily be removed and replaced, including a separa te section for each cable pull. Separate sections by heavy plasti c dividers with tabs, with all data sheets signed and dated by the person supervising the pull.

a. Site layout drawing with cable pulls numerica lly identified.

b. A list of equipment used, with calibration ce rtifications.

The manufacturer and quantity of lubricant used on pull.

c. The cable manufacturer and type of cable.

d. The dates of cable pulls, time of day, and am bient temperature.

e. The length of cable pull and calculated cable pulling tensions.

f. The actual cable pulling tensions encountered during pull.

1.5 QUALITY ASSURANCE

1.5.1 Precast Underground Structures

Submittal required for each type used. Provide cal culations and drawings for precast manholes and handholes bearing the seal of a registered professional engineer including:

a. Material description (i.e., f'c and Fy)

b. Manufacturer's printed assembly and installatio n instructions

c. Design calculations

d. Reinforcing shop drawings in accordance with ACI SP-66

e. Plans and elevations showing opening and pullin g-in iron locations and details

1.5.2 Regulatory Requirements

In each of the publications referred to herein, con sider the advisory provisions to be mandatory, as though the word, "mu st" had been substituted for "should" wherever it appears. Interpret refere nces in these publications to the "authority having jurisdiction, " or words of similar meaning, to mean the Contracting Officer. Equipmen t, materials, installation, and workmanship must be in accordance with the mandatory and advisory provisions of IEEE C2 and NFPA 70 unless more stringent requirements are specified or indicated.

1.5.3 Standard Products

Provide materials and equipment that are products o f manufacturers regularly engaged in the production of such product s which are of equal material, design and workmanship. Products must ha ve been in satisfactory commercial or industrial use for 2 years prior to b id opening. The 2-year period must include applications of equipment and m aterials under similar circumstances and of similar size. The product mus t have been for sale on the commercial market through advertisements, manuf acturers' catalogs, or brochures during the 2-year period. Where two or m ore items of the same class of equipment are required, these items must b e products of a single manufacturer; however, the component parts of the i tem need not be the products of the same manufacturer unless stated in this section.

1.5.3.1 Material and Equipment Manufacturing Date

Products manufactured more than 3 years prior to da te of delivery to site are not acceptable, unless specified otherwise.

PART 2 PRODUCTS

2.1 CONDUIT, DUCTS, AND FITTINGS

2.1.1 Plastic Conduit for Direct Burial and Riser Applications

UL 651 and NEMA TC 2, as indicated.

2.1.2 Innerduct

Provide corrugated polyethylene (PE) or PVC innerdu cts, or fabric-mesh innerducts, with pullwire. Size as indicated.

2.1.3 Duct Sealant

UL 94 , Class HBF. Provide high-expansion urethane foam duct sealant that expands and hardens to form a closed, chemically an d water resistant, rigid structure. Sealant must be compatible with common cable and wire jackets and capable of adhering to metals, plastics and con crete. Sealant must be capable of curing in temperature ranges of 35 degrees F to 95 degrees F .

Cured sealant must withstand temperature ranges of -20 degrees F to 200 degrees F without loss of function.

2.1.4 Fittings

2.1.4.1 PVC Conduit Fittings

UL 514B , UL 651 .

2.1.4.2 PVC Duct Fittings

NEMA TC 9.

2.2 LOW VOLTAGE INSULATED CONDUCTORS AND CABLES

Insulated conductors must be rated 600 volts and co nform to the requirements of NFPA 70 , including listing requirements. Wires and cables manufactured more than 12 months prior to date of d elivery to the site are not acceptable. Service entrance conductors must c onform to UL 854 , type

USE.

2.2.1 Conductor Types

Cable and duct sizes indicated are for copper condu ctors and THHN/THWN unless otherwise noted. Conductors No. 10 AWG and smaller must be solid.

Conductors No. 8 AWG and larger must be stranded. All conductors must be copper.

2.2.2 Conductor Material

Unless specified or indicated otherwise or required by NFPA 70 , wires in conduit, other than service entrance, must be 600-v olt, Type THWN/THHN conforming to UL 83 . Copper conductors must be annealed copper comply ing with ASTM B3 and ASTM B8.

2.2.3 In Duct

Cables must be single-conductor cable.

2.2.4 Cable Marking

Insulated conductors must have the date of manufact ure and other identification imprinted on the outer surface of ea ch cable at regular intervals throughout the cable length.

Identify each cable by means of a fiber, laminated plastic, or non-ferrous metal tags, or approved equal, in each manhole, han dhole, junction box, and each terminal. Each tag must contain the following information; cable type, conductor size, circuit number, circuit volta ge, cable destination and phase identification.

Conductors must be color coded. Provide conductor identification within each enclosure where a tap, splice, or termination is made. Conductor identification must be by color-coded insulated con ductors, plastic-coated self-sticking printed markers, colored nylon cable ties and plates, heat shrink type sleeves,or colored electrical tape. Co ntrol circuit terminations must be properly identified. Color mu st be green for grounding conductors and white for neutrals; except where neutrals of more than one system are installed in same raceway or bo x, other neutrals must be white with a different colored (not green) strip e for each. Color of ungrounded conductors in different voltage systems must be as follows:

a. 208/120 volt, three-phase

(1) Phase A - black

(2) Phase B - red

(3) Phase C - blue

b. 480/277 volt, three-phase

(1) Phase A - brown

(2) Phase B - orange

(3) Phase C - yellow

c. 120/240 volt, single phase: Black and red

2.3 LOW VOLTAGE WIRE CONNECTORS AND TERMINALS

Must provide a uniform compression over the entire conductor contact surface. Use solderless terminal lugs on stranded conductors.

a. For use with copper conductors: UL 486A-486B .

2.4 LOW VOLTAGE SPLICES

Provide splices in conductors with a compression co nnector on the conductor and by insulating and waterproofing using one of th e following methods which are suitable for continuous submersion in wat er and comply with

ANSI C119.1 .

2.4.1 Heat Shrinkable Splice

Provide heat shrinkable splice insulation by means of a thermoplastic adhesive sealant material applied in accordance wit h the manufacturer's written instructions.

2.4.2 Cold Shrink Rubber Splice

Provide a cold-shrink rubber splice which consists of EPDM rubber tube which has been factory stretched onto a spiraled co re which is removed during splice installation. The installation must not require heat or flame, or any additional materials such as covering or adhesive. It must be designed for use with inline compression type co nnectors, or indoor, outdoor, direct-burial or submerged locations.

2.5 TELECOMMUNICATIONS CABLING

Provide telecommunications cabling in accordance wi th Section 33 82 00

TELECOMMUNICATIONS OUTSIDE PLANT (OSP).

2.6 PULL ROPE

Plastic or flat pull line (bull line) having a mini mum tensile strength of 200 pounds .

2.7 GROUNDING AND BONDING

2.7.1 Driven Ground Rods

Provide copper-clad steel ground rods conforming to UL 467 not less than 3/4 inch in diameter by 10 feet in length. Sectional type rods may be used for rods 20 feet or longer.

2.7.2 Grounding Conductors

Stranded-bare copper conductors must conform to ASTM B8, Class B, soft-drawn unless otherwise indicated. Solid-bare copper conductors must conform to ASTM B1 for sizes No. 8 and smaller. Insulated conductors must be of the same material as phase conductors and gre en color-coded, except that conductors must be rated no more than 600 volt s. Aluminum is not acceptable.

2.8 CAST-IN-PLACE CONCRETE

Provide concrete in accordance with Section 03 30 00 CAST-IN-PLACE CONCRETE. In addition, provide concrete for encase ment of underground ducts with 3000 psi minimum 28-day compressive strength. Concrete associated with electrical work for other than enca sement of underground ducts must be 4000 psi minimum 28-day compressive strength unless specifi ed otherwise.

2.9 UNDERGROUND STRUCTURES

Provide precast concrete underground structures or standard type cast-in-place manhole types as indicated, conformin g to ASTM C857 and ASTM C478. Top, walls, and bottom must consist of reinforce d concrete.

Walls and bottom must be of monolithic concrete con struction. Locate duct entrances and windows near the corners of structure s to facilitate cable racking. Covers must fit the frames without undue play. Form steel and iron to shape and size with sharp lines and angles. Castings must be free from warp and blow holes that may impair strength o r appearance. Exposed metal must have a smooth finish and sharp lines and arises. Provide necessary lugs, rabbets, and brackets. Set pulling -in irons and other built-in items in place before depositing concrete. Install a pulling-in iron in the wall opposite each duct line entrance. Cable racks, including rack arms and insulators, must be adequate to accom modate the cable.

2.9.1 Cast-In-Place Concrete Structures

Concrete must conform to Section 03 30 00 CAST-IN-PLACE CONCRETE.

2.9.2 Precast Concrete Structures, Risers and Top s

Precast concrete underground structures may be prov ided in lieu of cast-in-place subject to the requirements specified below. Precast units must be the product of a manufacturer regularly eng aged in the manufacture of precast concrete products, including precast man holes.

2.9.2.1 General

Precast concrete structures must have the same accessories and facilities as required for cast-in-place structures. Likewise , precast structures must have plan area and clear heights not less than those of cast-in-place structures. Concrete materials and methods of cons truction must be the same as for cast-in-place concrete construction, as modified herein. Slope in floor may be omitted provided precast sections a re poured in reinforced steel forms. Concrete for precast work must have a 28-day compressive strength of not less than 4000 psi . Structures may be precast to the design and details indicated for cast-in-place cons truction, precast monolithically and placed as a unit, or structures may be assembled sections, designed and produced by the manufacturer in accordance with the requirements specified. Structures must be identif ied with the manufacturer's name embedded in or otherwise perman ently attached to an interior wall face.

2.9.2.2 Design for Precast Structures

ACI 318M . In the absence of detailed on-site soil informat ion, design for the following soil parameters/site conditions:

a. Angle of Internal Friction (phi) = 30 degrees

b. Unit Weight of Soil (Dry) = 110 pcf , (Saturated) = 130 pcf

c. Coefficient of Lateral Earth Pressure (Ka) = 0. 33

d. Ground Water Level = 3 feet below ground elevation

e. Vertical design loads must include full dead, s uperimposed dead, and live loads including a 30 percent magnification fac tor for impact.

Live loads must consider all types and magnitudes o f vehicular (automotive, industrial, or aircraft) traffic to be encountered. The minimum design vertical load must be for H20 highwa y loading per

AASHTO HB-17.

f. Horizontal design loads must include full geost atic and hydrostatic pressures for the soil parameters, water table, and depth of installation to be encountered. Also, horizontal l oads imposed by adjacent structure foundations, and horizontal load components of vertical design loads, including impact, must be co nsidered, along with a pulling-in iron design load of 6000 pounds .

g. Each structural component must be designed for the load combination and positioning resulting in the maximum shear and mome nt for thatparticular component.

h. Design must also consider the live loads induce d in the handling, installation, and backfilling of the manholes. Pro vide lifting devices to ensure structural integrity during handling and installation.

2.9.2.3 Construction

Structure top, bottom, and wall must be of a unifor m thickness of not less than 6 inches . Thin-walled knock-out panels for designed or fut ure duct bank entrances are not permitted. Provide quantity , size, and location of duct bank entrance windows as directed, and cast co mpletely open by the precaster. Size of windows must exceed the nominal duct bank envelope dimensions by at least 12 inches vertically and horizontally to preclude in-field window modifications made necessary by duc t bank misalignment.

However, the sides of precast windows must be a min imum of 6 inches from the inside surface of adjacent walls, floors, or ce ilings. Form the perimeter of precast window openings to have a keye d or inward flared surface to provide a positive interlock with the ma ting duct bank envelope. Provide welded wire fabric reinforcing t hrough window openings for in-field cutting and flaring into duct bank env elopes. Provide additional reinforcing steel comprised of at least two No. 4 bars around window openings. Provide drain sumps a minimum of 12 inches in diameter and 4 inches deep for precast structures.

2.9.2.4 Joints

Provide tongue-and-groove joints on mating edges of precast components.

Shiplap joints are not allowed. Design joints to f irmly interlock adjoining components and to provide waterproof junc tions and adequate shear transfer. Seal joints watertight using preformed p lastic strip conforming to ASTM C990. Install sealing material in strict accordance with the sealant manufacturer's printed instructions. Provi de waterproofing at conduit/duct entrances into structures, and where a ccess frame meets the top slab, provide continuous grout seal.

2.9.3 Handhole Frames and Covers

Frames and covers of steel must be welded by qualif ied welders in accordance with standard commercial practice. Stee l covers must be rolled-steel floor plate having an approved antisli p surface. Hinges must be of stainless steel with bronze hinge pin, 5 by 5 inches by approximately 3/16 inch thick, without screw holes, and must be for full s urface application by fillet welding. Hinges must have no nremovable pins and five knuckles. The surfaces of plates under hinges must be true after the removal of raised antislip surface, by grinding or other approved method.

2.9.4 Composite/Fiberglass Handholes and Covers

ANSI/SCTE 77 . Provide handholes and covers of polymer concrete , reinforced with heavy weave fiberglass with a design load (Tie r rating) appropriate for or greater than the intended use. All covers a re required to have the Tier level rating embossed on the surface and this rating must not exceed the design load of the box.

2.10 CABLE SUPPORTS (RACKS, ARMS, AND INSULATORS)

The metal portion of racks and arms must be zinc-co ated after fabrication.

2.10.1 Cable Rack Stanchions

The wall bracket or stanchion must be 4 inches by approximately 1-1/2 inch by 3/16 inch channel steel, or 4 inches by approximately 1 inch glass-reinforced nylon with recessed bolt mounting holes, 48 inches long (minimum) in manholes. Slots for mounting cable ra ck arms must be spaced at 8 inch intervals.

2.10.2 Rack Arms

Cable rack arms must be steel or malleable iron or glass reinforced nylon and must be of the removable type. Rack arm length must be a minimum of 8 inches and a maximum of 12 inches .

2.10.3 Insulators

Insulators for metal rack arms must be dry-process glazed porcelain.

Insulators are not required for nylon arms.

PART 3 EXECUTION

3.1 INSTALLATION

Install equipment and devices in accordance with th e manufacturer's published instructions and with the requirements an d recommendations of NFPA 70 and IEEE C2 as applicable. In addition to these requirements, install telecommunications in accordance with TIA-758 and RUS Bull 1751F-644 .

3.2 CABLE INSPECTION

Inspect each cable reel for correct storage positio ns, signs of physical damage, and broken end seals prior to installation. If end seal is broken, remove moisture from cable prior to installation in accordance with the cable manufacturer's recommendations.

3.3 CABLE INSTALLATION PLAN AND PROCEDURE

Obtain from the manufacturer an installation manual or set of instructions which addresses such aspects as cable construction, insulation type, cable diameter, bending radius, cable temperature limits for installation, lubricants, coefficient of friction, conduit cleani ng, storage procedures, moisture seals, testing for and purging moisture, m aximum allowable pulling tension, and maximum allowable sidewall bearing pre ssure. Submit along with the manufacturer's instructions in accordance with SUBMITTALS.

Install cable strictly in accordance with the cable manufacturer's recommendations and the approved installation plan.

3.4 UNDERGROUND STRUCTURE CONSTRUCTION

Provide standard type cast-in-place construction as specified herein and as indicated, or precast construction as specified her ein. Horizontal concrete surfaces of floors must have a smooth trow el finish. Cure concrete by applying two coats of white pigmented m embrane forming-curing compound in strict accordance with the manufacturer 's printed instructions, except that precast concrete may be steam cured. C uring compound must conform to ASTM C309. Locate duct entrances and windows in the center of end walls (shorter) and near the corners of sidewal ls (longer) to facilitate cable racking and splicing. Covers for underground structures must fit the frames without undue play. Steel and iron must be formed to shape and size with sharp lines and angles. Castin gs must be free from warp and blow holes that may impair strength or app earance. Exposed metal must have a smooth finish and sharp lines and arise s. Provide necessary lugs, rabbets, and brackets. Set pulling-in irons and other built-in items in place before depositing concrete. Manhole locat ions, as indicated, are approximate. Coordinate exact manhole locations wi th other utilities and finished grading and paving.

3.4.1 Precast Concrete Construction

Set commercial precast structures on 6 inches of level, 90 percent compacted granular fill, 3/4 inch to 1 inch size, extending 12 inches beyond the structure on each side. Compact granula r fill by a minimum of four passes with a plate type vibrator. Installati on must additionally conform to the manufacturer's instructions.

3.4.2 Pulling-In Irons

Provide steel bars bent as indicated, and cast in t he walls and floors.

Alternatively, pipe sleeves may be precast into the walls and floors where required to accept U-bolts or other types of pullin g-in devices possessing the strengths and clearances stated herein. The fi nal installation of pulling-in devices must be made permanent. Cover a nd seal exterior projections of thru-wall type pulling-in devices wi th an appropriate protective coating. In the floor the irons must be a minimum of 6 inches from the edge of the sump, and in the walls the iro ns must be located within 6 inches of the projected center of the duct bank pattern o r precast window in the opposite wall. However, the pulling- in iron must not be located within 6 inches of an adjacent interior surface, or duct or precas t window located within the same wall as the iron. I f a pulling-in iron cannot be located directly opposite the correspondi ng duct bank or precast window due to this clearance limitation, locate the iron directly above or below the projected center of the duct bank pattern or precast window the minimum distance required to preserve the 6 inch clearance previously stated. In the case of directly opposing precast w indows, pulling-in irons consisting of a 3 foot length of No. 5 reinforcing bar, formed into a hairpin, may be cast-in-place within the precast wi ndows simultaneously with the end of the corresponding duct bank envelop e. Irons installed in this manner must be positioned directly in line wit h, or when not possible, directly above or below the projected center of the duct bank pattern entering the opposite wall, while maintaining a min imum clear distance of 3 inches from any edge of the cast-in-place duct bank envel ope or any individual duct. Pulling-in irons must have a clea r projection into the structure of approximately 4 inches and must be designed to withstand a minimum pulling-in load of 6000 pounds . Irons must be hot-dipped galvanized after fabrication.

3.4.3 Cable Racks, Arms and Insulators

Cable racks, arms and insulators must be sufficient to accommodate the cables. Space racks in power manholes not more tha n 3 feet apart, and provide each manhole wall with a minimum of two rac ks. Space racks in signal manholes not more than 16 1/2 inches apart with the end rack being no further than 12 inches from the adjacent wall. Methods of anchoring cable racks must be as follows:

a. Provide a 5/8 inch diameter by 5 inch long anchor bolt with 3 inch foot cast in structure wall with 2 inch protrusion of threaded portion of bolt into structure. Provide 5/8 inch steel square head nut on each anchor bolt. Coat threads of anchor bolts with sui table coating immediately prior to installing nuts.

b. Provide concrete channel insert with a minimum load rating of 800 pounds per foot . Insert channel must be steel of the same length as "vertical rack channel;" channel insert must be cas t flush in structure wall. Provide 5/8 inch steel nuts in channel insert to receive 5/8 inch diameter by 3 inch long steel, square head anchor bolts.

c. Provide concrete "spot insert" at each anchor b olt location, cast flush in structure wall. Each insert must have minimum 800 pound load rating. Provide 5/8 inch diameter by 3 inch long steel, square head anchor bolt at each anchor point. Coat threads of anchor bolts with suitable coating immediately prior to installing bo lts.

3.4.4 Field Painting

Cast-iron frames and covers not buried in concrete or masonry must be cleaned of mortar, rust, grease, dirt and other del eterious materials, and given a coat of bituminous paint.

3.5 UNDERGROUND CONDUIT AND DUCT SYSTEMS

3.5.1 Requirements

Run conduit in straight lines except where a change of direction is necessary. Provide numbers and sizes of ducts as i ndicated. Ducts must have a continuous slope downward toward underground structures and away from buildings, laid with a minimum slope of 3 inches per 100 feet .

Depending on the contour of the finished grade, the high-point may be at a terminal, a manhole, a handhole, or between manhole s or handholes. Provide ducts with end bells whenever duct lines terminate in structures.

Perform changes in ductbank direction as follows:

a. Short-radius manufactured 90-degree duct bends may be used only for pole or equipment risers, unless specifically indic ated as acceptable.

b. The minimum manufactured bend radius must be 18 inches for ducts of less than 3 inch diameter, and 36 inches for ducts 3 inches or greater in diameter.

c. As an exception to the bend radius required abo ve, provide field manufactured longsweep bends having a minimum radiu s of 25 feet for a change of direction of more than 5 degrees, either horizontally or vertically, using a combination of curved and strai ght sections.

Maximum manufactured curved sections: 30 degrees.

3.5.2 Treatment

Ducts must be kept clean of concrete, dirt, or fore ign substances during construction. Field cuts requiring tapers must be made with proper tools and match factory tapers. A coupling recommended b y the duct manufacturer must be used whenever an existing duct is connected to a duct of different material or shape. Ducts must be stored to avoid w arping and deterioration with ends sufficiently plugged to prevent entry of any water or solid substances. Ducts must be thoroughly cleaned befor e being laid. Plastic ducts must be stored on a flat surface and protecte d from the direct rays of the sun.

3.5.3 Conduit Cleaning

As each conduit run is completed, for conduit sizes 3 inches and larger, draw a flexible testing mandrel approximately 12 inches long with a diameter less than the inside diameter of the condu it through the conduit.

After which, draw a stiff bristle brush through unt il conduit is clear of particles of earth, sand and gravel; then immediate ly install conduit plugs. For conduit sizes less than 3 inches , draw a stiff bristle brush through until conduit is clear of particles of eart h, sand and gravel; then immediately install conduit plugs.

3.5.4 Jacking and Drilling Under Roads and Struct ures

Conduits to be installed under existing paved areas which are not to be disturbed, and under roads and railroad tracks, mus t be zinc-coated, rigid steel, jacked into place. Where ducts are jacked u nder existing pavement, rigid steel conduit must be installed because of it s strength. To protect the corrosion-resistant conduit coating, predrillin g or installing conduit inside a larger iron pipe sleeve (jack-and-sleeve) is required. For crossings of existing railroads and airfield paveme nts greater than 50 feet in length, the predrilling method or the jack-and-s leeve method will be used. Separators or spacing blocks must be made of steel, concrete, plastic, or a combination of these materials placed not farther apart than 4 feet on centers.

3.5.5 Galvanized Conduit Concrete Penetrations

Galvanized conduits which penetrate concrete (slabs , pavement, and walls) in wet locations must be PVC coated and must extend from at least 2 inches within the concrete to the first coupling or fittin g outside the concrete (minimum of 6 inches from penetration).

3.5.6 Multiple Conduits

Separate multiple conduits by a minimum distance of 3 inches , except that light and power conduits must be separated from con trol, signal, and telephone conduits by a minimum distance of 12 inches . Stagger the joints of the conduits by rows (horizontally) and layers ( vertically) to strengthen the conduit assembly. Provide plastic d uct spacers that interlock vertically and horizontally. Spacer asse mbly must consist of base spacers, intermediate spacers, ties, and locki ng device on top to provide a completely enclosed and locked-in conduit assembly. Install spacers per manufacturer's instructions, but provid e a minimum of two spacer assemblies per 10 feet of conduit assembly.

3.5.7 Conduit Plugs and Pull Rope

New conduit indicated as being unused or empty must be provided with plugs on each end. Plugs must contain a weephole or scre en to allow water drainage. Provide a plastic pull rope having 3 feet of slack at each end of unused or empty conduits.

3.5.8 Conduit and Duct Without Concrete Encasemen t

Depths to top of the conduit must be not less than 24 inches below finished grade. Provide not less than 3 inches clearance from the conduit to each side of the trench. Grade bottom of trench smooth; where rock, soft spots, or sharp-edged materials are encountered, excavate the bottom for an additional 3 inches , fill and tamp level with original bottom with san d or earth free from particles, that would be retained o n a 1/4 inch sieve. The first 6 inch layer of backfill cover must be sand compacted as previously specified. The rest of the excavation must be back filled and compacted in 3 to 6 inch layers. Provide color, type and depth of warning t ape as specified in Section 31 23 00.00 20 EXCAVATION AND FILL.

3.5.8.1 Encasement Under Roads and Structures

Under roads, paved areas, and railroad tracks, inst all conduits in concrete encasement of rectangular cross-section providing a minimum of 3 inch concrete cover around ducts. Concrete encasement m ust extend at least 5 feet beyond the edges of paved areas and roads, and 12 feet beyond the rails on each side of railroad tracks. Depths to t op of the concrete envelope must be not less than 24 inches below finished grade.

3.5.9 Duct Encased in Concrete

Construct underground duct lines of individual cond uits encased in concrete. Depths to top of the concrete envelope m ust be not less than 18 inches below finished grade, except under roads and pavem ent, concrete envelope must be not less than 24 inches below finished grade. Do not mix different kinds of conduit in any one duct bank. C oncrete encasement surrounding the bank must be rectangular in cross-s ection and must provide at least 3 inches of concrete cover for ducts. Separate conduits by a minimum concrete thickness of 3 inches . Before pouring concrete, anchor duct bank assemblies to prevent the assemblies from floating during concrete pouring. Anchoring must be done by drivin g reinforcing rods adjacent to duct spacer assemblies and attaching th e rods to the spacer assembly. Provide color, type and depth of warning tape as specified in Section 31 23 00.00 20 EXCAVATION AND FILL.

3.5.9.1 Connections to Manholes

Duct bank envelopes connecting to underground struc tures must be flared to have enlarged cross-section at the manhole entrance to provide additional shear strength. Dimensions of the flared cross-sec tion must be larger than the corresponding manhole opening dimensions by no less than 12 inches in each direction. Perimeter of the duct bank opening in the underground structure must be flared toward the inside or keyed to provide a positive interlock between the duct bank and the wall of the structure. Use vibrators when this portion of the encasement is po ured to assure a seal between the envelope and the wall of the structure.

3.5.9.2 Connections to Existing Underground Struc tures

For duct bank connections to existing structures, b reak the structure wall out to the dimensions required and preserve steel i n the structure wall.

Cut steel and extend into the duct bank envelope. Chip the perimeter surface of the duct bank opening to form a key or f lared surface, providing a positive connection with the duct bank envelope.

3.5.9.3 Partially Completed Duct Banks

During construction wherever a construction joint i s necessary in a duct bank, prevent debris such as mud, and, and dirt fro m entering ducts by providing suitable conduit plugs. Fit concrete env elope of a partially completed duct bank with reinforcing steel extendin g a minimum of 2 feet back into the envelope and a minimum of 2 feet beyond the end of the envelope. Provide one No. 4 bar in each corner, 3 inches from the edge of the envelope. Secure corner bars with two No. 3 ti es, spaced approximately one foot apart. Restrain reinforcing assembly from moving during concrete pouring.

3.5.10 Duct Sealing

Seal all electrical penetrations for radon mitigati on, maintaining integrity of the vapor barrier, and to prevent infi ltration of air, insects, and vermin.

3.6 CABLE PULLING

Test existing duct lines with a mandrel and thoroug hly swab out to remove foreign material before pulling cables. Pull cable s down grade with the feed-in point at the manhole or buildings of the hi ghest elevation. Use flexible cable feeds to convey cables through manho le opening and into duct runs. Do not exceed the specified cable bending ra dii when installing cable under any conditions, including turnups into switches, transformers, switchgear, switchboards, and other enclosures. Ca ble with tape or wire shield must have a bending radius not less than 12 times the overall diameter of the completed cable. If basket-grip ty pe cable-pulling devices are used to pull cable in place, cut off the sectio n of cable under the grip before splicing and terminating.

3.6.1 Cable Lubricants

Use lubricants that are specifically recommended by the cable manufacturer for assisting in pulling jacketed cables.

3.7 CABLES IN UNDERGROUND STRUCTURES

Do not install cables utilizing the shortest path b etween penetrations, but route along those walls providing the longest route and the maximum spare cable lengths. Form cables to closely parallel wall s, not to interfere with duct entrances, and support on brackets and cable i nsulators. Support cable splices in underground structures by racks on each side of the splice. Locate splices to prevent cyclic bending i n the spliced sheath.

Install cables at middle and bottom of cable racks, leaving top space open for future cables, except as otherwise indicated fo r existing installations. Provide one spare three-insulator r ack arm for each cable rack in each underground structure.

3.7.1 Cable Tag Installation

Install cable tags in each manhole as specified, in cluding each splice.

Tag wire and cable provided by this contract. Inst all cable tags over the fireproofing, if any, and locate the tags so that t hey are clearly visible without disturbing any cabling or wiring in the man holes.

3.8 LOW VOLTAGE CABLE SPLICING AND TERMINATING

Make terminations and splices with materials and me thods as indicated or specified herein and as designated by the written i nstructions of the manufacturer. Do not allow the cables to be moved until after the splicing material has completely set.

3.9 GROUNDING SYSTEMS

NFPA 70 and IEEE C2 , except provide grounding systems with a resistanc e to solid earth ground not exceeding 25 ohms.

3.9.1 Grounding Electrodes

Provide cone pointed driven ground rods driven full depth plus 12 inches , installed to provide an earth ground of the appropr iate value for the particular equipment being grounded.

If the specified ground resistance is not met, an a dditional ground rod must be provided in accordance with the requirement s of NFPA 70 (placed not less than 6 feet from the first rod). Should the r esultant (combined) resistance exceed the specified resistance, measure d not less than 48 hours after rainfall, notify the Contracting Officer imme diately.

3.9.2 Grounding Connections

Make grounding connections which are buried or othe rwise normally inaccessible, by exothermic weld or compression con nector.

a. Make exothermic welds strictly in accordance wi th the weld manufacturer's written recommendations. Welds whic h are "puffed up" or which show convex surfaces indicating improper clea ning are not acceptable. Mechanical connectors are not required at exothermic welds.

b. Make compression connections using a hydraulic compression tool to provide the correct circumferential pressure. Tool s and dies must be as recommended by the manufacturer. An embossing d ie code or other standard method must provide visible indication tha t a connector has been adequately compressed on the ground wire.

3.9.3 Grounding Conductors

Provide bare grounding conductors, except where ins talled in conduit with associated phase conductors. Ground cable sheaths, cable shields, conduit, and equipment with No. 6 AWG. Ground other noncurre nt-carrying metal parts and equipment frames of metal-enclosed equipment. Ground metallic frames and covers of handholes and pull boxes with a braid ed, copper ground strap with equivalent ampacity of No. 6 AWG. Provide dir ect connections to the grounding conductor with 600 v insulated, full-size conductor for each grounded neutral of each feeder circuit, which is s pliced within the manhole.

3.9.4 Ground Cable Crossing Expansion Joints

Protect ground cables crossing expansion joints or similar separations in structures and pavements by use of approved devices or methods of installation which provide the necessary slack in t he cable across the joint to permit movement. Use stranded or other ap proved flexible copper cable across such separations.

3.9.5 Manhole Grounding

Loop a 4/0 AWG grounding conductor around the inter ior perimeter, approximately 12 inches above finished floor. Secure the conductor to the manhole walls at intervals not exceeding 36 inches . Connect the conductor to the manhole grounding electrode with 4/0 AWG con ductor. Connect all incoming 4/0 grounding conductors to the ground loo p adjacent to the point of entry into the manhole. Bond the ground loop to all cable shields, metal cable racks, and other metal equipment with a minimum 6 AWG conductor.

3.10 EXCAVATING, BACKFILLING, AND COMPACTING

Provide in accordance with NFPA 70 and Section 31 23 00.00 20 EXCAVATION

AND FILL.

3.10.1 Reconditioning of Surfaces

3.10.1.1 Unpaved Surfaces

Restore to their original elevation and condition u npaved surfaces disturbed during installation of duct. Preserve so d and topsoil removed during excavation and reinstall after backfilling i s completed. Replace sod that is damaged by sod of quality equal to that removed. When the surface is disturbed in a newly seeded area, re-see d the restored surface with the same quantity and formula of seed as that used in the original seeding, and provide topsoiling, fertilizing, limin g, seeding, sodding, sprigging, or mulching.

3.10.1.2 Paving Repairs

Where trenches, pits, or other excavations are made in existing roadways and other areas of pavement where surface treatment of any kind exists , restore such surface treatment or pavement the same thickness and in the same kind as previously existed, except as otherwis e specified, and to match and tie into the adjacent and surrounding exi sting surfaces.

3.11 CAST-IN-PLACE CONCRETE

Provide concrete in accordance with Section 03 30 00 CAST-IN-PLACE CONCRETE.

3.11.1 Concrete Slabs (Pads) for Equipment

Unless otherwise indicated, the slab must be at lea st 8 inches thick, reinforced with a 6 by 6 - W2.9 by W2.9 mesh, placed uniformly 4 inches from the top of the slab. Slab must be placed on a 6 inch thick, well-compacted gravel base. Top of concrete slab m ust be approximately 4 inches above finished grade with gradual slope for draina ge. Edges above grade must have 1/2 inch chamfer. Slab must be of adequate size to project at least 8 inches beyond the equipment.

Stub up conduits, with bushings, 2 inches into cable wells in the concrete pad. Coordinate dimensions of cable wells with tra nsformer cable training areas.

3.12 FIELD QUALITY CONTROL

3.12.1 Performance of Field Acceptance Checks and Tests

Perform in accordance with the manufacturer's recom mendations, and include the following visual and mechanical inspections and electrical tests, performed in accordance with NETA ATS.

3.12.1.1 Low Voltage Cables, 600-Volt

Perform tests after installation of cable, splices and terminations and before terminating to equipment or splicing to exis ting circuits.

a. Visual and Mechanical Inspection

(1) Inspect exposed cable sections for physical dam age.

(2) Verify that cable is supplied and connected in accordance with contract plans and specifications.

(3) Verify tightness of accessible bolted electrica l connections.

(4) Inspect compression-applied connectors for corr ect cable match and indentation.

(5) Visually inspect jacket and insulation conditio n.

(6) Inspect for proper phase identification and arr angement.

b. Electrical Tests

(1) Perform insulation resistance tests on wiring No. 6 AWG and larger diameter using instrument which applies volt age of approximately 1000 volts dc for one minute.

(2) Perform continuity tests to insure correct cabl e connection.

3.12.1.2 Grounding System

a. Visual and mechanical inspection

Inspect ground system for compliance with contract plans and specifications.

b. Electrical tests

Perform ground-impedance measurements utilizing the fall-of-potential method in accordance with IEEE 81 . On systems consisting of interconnected ground rods, perform tests after int erconnections are complete. On systems consisting of a single ground rod perform tests before any wire is connected. Take measurements in normally dry weather, not less than 48 hours after rainfall. Us e a portable ground resistance tester in accordance with manufacturer's instructions to test each ground or group of grounds. The instrume nt must be equipped with a meter reading directly in ohms or fractions thereof to indicate the ground value of the ground rod or grounding sys tems under test.

Provide site diagram indicating location of test pr obes with associated distances, and provide a plot of resistance vs. dis tance.

3.12.2 Follow-Up Verification

Upon completion of acceptance checks and tests, sho w by demonstration in service that circuits and devices are in good opera ting condition and properly performing the intended function. As an e xception to requirements stated elsewhere in the contract, the Contracting O fficer must be given 5 working days advance notice of the dates and times of checking and testing.

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