SECTION RACEWAYS AND BOXES

Transcription

1 SECTION RACEWAYS AND BOXES PART 1 GENERAL 1.01 DESCRIPTION A. This section covers the contract item Raceways and Boxes which includes fittings, bushings, hubs, identification tags, clamp supports, transition fittings, expansion and deflection fittings, joint and conduit sealing, and other accessories as required. The conduit shall include conduits of various types and sizes. Junction boxes shall have cover plates. B. The contract item also includes the earthwork, excavation, concrete embedment, and underground warning tape for underground electrical work RELATED SECTIONS A. Supplementary General Conditions, General Conditions, Division 1 sections, and Drawings apply to this section. This section may require direct correlation with the following sections of the contract: 1. Section Basic Electrical Materials and Methods. 2. Section Insulated Wire and Cable REFERENCES A. The following publications form a part of this specification to the extent referenced. Application of these publications shall conform to Document Interpretation of the Contract, Paragraph 2: 1. American National Standards Institute (ANSI). 2. California General Order 128 (G.O. 128). 3. National Electrical Code (NEC). 4. National Electrical Manufacturer s Association (NEMA). 5. National Electrical Safety Code (NESC). 6. Underwriters Laboratories, Inc. (UL) N-10

2 7. CEC (California Electric Code). B. Materials for the conduit system shall conform to the industry standards as applicable and as specified SUBMITTALS A. Submit the following: 1. Product catalog data. 2. Conduit system layout. PART 2 PRODUCTS 2.01 CONDUIT A. Plastic Coated Rigid Steel Conduit: 1. Plastic coated rigid steel conduit shall be hot-dip galvanized including threads before coating, and shall conform to ANSI C80.1. Conduit shall have a polyvinyl chloride or high-density polyethylene coating not less than 20 mils thick applied over the galvanizing. Uncoated rigid steel conduit wrapped with PVC tape will not be accepted. 2. Conduit sizes shall be from 3/4 inch to 6 inches. 3. Fittings for coated conduit shall be coated with the same material as the conduits and shall be the products of the same manufacturer. 4. Plastic coated rigid steel conduit shall be as manufactured by Pittsburgh Standard Conduit Co., Rob-Kote; General Steel Industries Inc., X-Tru-Coat; or equal. B. Intermediate Metal Conduit: Intermediate metal conduit (IMC) shall be hot-dip galvanized, including threads, and shall conform to UL 1242 and ANSI C80.6. Each length shall bear the UL label, name of manufacturer, and, at intervals of 30 inches, the letters IMC. 1. IMC sizes shall be from 3/4 inch minimum to 4 inches maximum. 2. Intermediate metal conduit shall be Allied Tube and Conduit; Western Tube and Conduit Corp.; or equal. C. Liquid-tight Flexible Metal Conduit: Liquid-tight flexible metal conduit shall be galvanized steel with a copper bonding conductor between the N-10

3 spiral segments, an extruded synthetic jacket overall and shall conform to UL Flexible conduit sizes shall be 3/4 inch minimum to 4 inches maximum. 2. Flexible conduit shall be Carol Cable, UTXL; International Metal Hose, ULLT; or equal. D. Rigid Nonmetallic Conduit: Rigid nonmetallic conduit shall be smoothwall, polyvinyl chloride (PVC) Schedule 80 conduit. 1. PVC conduit sizes shall be as shown. 2. PVC conduit shall be Carlon Electrical Sciences Inc.; Condux International Inc.; or equal. 3. PVC conduits shall be gray in color. E. Conduit Fittings: 1. Conduit fittings for intermediate metal conduits shall be galvanized malleable iron conforming to ANSI C Fittings for intermediate metal conduit shall be factory coated and products of the same manufacturer as the conduit. 3. Fittings for liquid-tight flexible metallic conduit shall be products of the same manufacturer as the conduit. 4. Fittings for nonmetallic conduit shall be products of the same manufacturer as the conduit JUNCTION BOXES A. Conduit Body: Conduit bodies shall be galvanized malleable iron complete with gaskets and covers. 1. Conduit bodies shall be Crouse-Hinds, Form 8 Condulet; Appleton, Form 35 Unilet; or equal. 2. Conduit bodies for coated conduit shall be factory coated and products of the same manufacturer as the conduit. B. Cast Outlet and Junction Boxes: Outlet and junction boxes shall conform to UL 514. Junction boxes shall be single or multigang Type FD square, Type GRF or JB (round), minimum 3 inches deep with Type DS and FSK or JBK covers. Boxes shall be weatherproof for outdoor installation N-10

4 C. Electronic enclosure shall also be provided for WLS cables in the water well cabinet. The enclosure shall be 20 inch by 20 inch by 20 inch CONCRETE PULL BOXES A. Pull boxes shall be Farni Corp.; Christy; or equal, of the sizes shown. Depth of boxes shall be as required to obtain the required drain slope. Covers shall be the concrete bolt down or parkway type and shall have H20 rating. Pull boxes shall be equipped with pulli ng irons and cable racks. Lettering on the covers shall be Electrical, or Communication, as applicable. A cast iron grate with frame shall be provided at the drain hole. Grate shall be Alhambra, No. A2010; Apex Steel, No. X-3100; or equal DUCT BANK A. The duct bank includes trenching, conduits, ground conductor, lean concrete material, warning tape and backfill. 1. The lean concrete material shall conform to Section Concrete and Reinforcing Steel. 2. Backfill shall conform to Section Earthwork. 3. Ground conductor shall conform to Section Grounding System GATE CONTROL CABINET (CCA) A. The gate control cabinet includes the enclosure, backboard, devices, terminal block assemblies, wiring and appurtenances in the Motor Control Center (MCC). 1. Enclosure: a. The enclosure shall be NEMA Type 12. The cabinet shall have continuous welded seams ground smooth, gasketed doors with continuous hinges, three-point latch and padlockable handle. b. Backboard shall have a 3/4 inch APA, ACX EXT plywood backboard finished with two coats of nonconductive, fire retardant varnish. c. Complete cabinet shall be phosphatized and receive two coats of enamel. Interior shall be white, and exterior shall be ANSI Z55.1, No 61, light gray. Enclosure shall be anchored to the concrete block wall using anchors as specified in Section Materials and Workmanship N-10

5 d. The enclosure shall be Hoffman, Catalog No. A366012WFLP; B-Line, Catalog No D; or equal. 2. Control Devices: a. Selector switches and indicating lights shall be G. E. Co., Type CR104P; Furnas, Class 52; or approved equal. b. Terminal blocks nameplates, accessories, and wiring shall be as specified in Section Basic Electrical Materials and Methods. c. Control devices and indicating lights shall be oiltight. Lights shall be LED type. d. Control relays shall be general purpose with 120 volt coil and shall include: 1) Four form C contacts (DPDT) rated for 120 Vac, 3 amperes minimum. 2) Socket with mounting hardware. 3) Relays shall be TYCO Electronics; Potter Brumfield, KHA Series; Honeywell, SZR Series; or equal UNDERGROUND WARNING TAPE A. Warning tape shall be bright red plastic with 3 inch minimum width. The tape shall not delaminate when wet and shall be resistant to insects, acids, alkalis, and other corrosive elements in the soil. B. Warning shall be CAUTION BURIED ELECTRICAL LINE BELOW in bold black letters 1 to 1-1/2 inches high and shall be repeated approximately every 30 inches. The letters shall be nonerasable and shall last with the tape for a minimum of 40 years. C. Warning tape shall have a metallic coating to provide for detection by metal detector. D. The warning tape shall be Condux International, Inc.; Allen Systems, Inc.; or equal N-10

6 PART 3 EXECUTION 3.01 INSTALLATION A. General: Conduit shall be installed with necessary fittings and supports, only strap type wrenches shall be used. 1. Conduit bends shall be free from kinks, indentations, or flattened surfaces and shall be made in long sweeps wherever possible. Bending radius shall not be less than required by the NEC. Bends shall be made cold to prevent damage to protective coatings. 2. PVC coated conduits shall be bent using bending shoes recommended by the conduit manufacturer. 3. Field cuts shall be made with a metal cutting saw. Burrs and sharp edges at the ends of metal conduits shall be removed. 4. Male threads shall be tapered. Running threads will not be allowed. Conduit threads shall be coated with a graphite or zinc sealing material before making joints. B. Applications: 1. Indoor and outdoor exposed conduit and conduit embedded in concrete shall be IMC except as shown. 2. Conduits from the elbow to the structure in direct burial shall be plastic coated rigid steel. 3. Conduits for utility connections shall be direct buried, rigid nonmetal conduit. Underground warning tape shall be placed 12 inches above conduit. 4. Conduits for equipment connections subject to movement, noise transmission or vibration shall be terminated using a length of liquid-tight flexible metal conduit in accordance with the NEC. C. Methods: 1. Buried conduits and duct shall be installed in trenches, surrounded by 3 inches of sand or approved material, and shall have burial depth not less than specified in NEC Article and as shown. Installation shall be in accordance with the NEC and G.O. 128 as applicable N-10

7 2. Conduit runs shall be made with approved couplings, unions and joints to provide electrical continuity and maintain the coating system. Only strap type wrenches shall be used. 3. Conduit runs shall be installed in the approximate locations shown and shall be routed to avoid interference with structures, foundations and equipment. 4. Indoor and outdoor exposed conduits shall be surface mounted on concrete block walls and furred block walls or supported on structural members. a. Attachment to walls shall be made using standard conduit clamps, back plates and stainless steel expansion anchors. b. Attachment to structural members shall be made without damage to the members. Galvanized continuous slotted channel shall be installed where needed for supporting conduits and boxes. 5. Conduit to be embedded in concrete shall be held securely in position while concrete is placed. Embedded conduits shall be located in the center one third of wall or slab. Conduits may be stacked in no more than two tiers, with not less than 2 inches between tiers. Conduits within a tier shall be spaced three diameters apart, except at stubout locations. 6. After conduit is installed and before concrete or backfill is placed, a mandrel shall be drawn through the conduit runs in the Engineer s presence. If the mandrel fails to pass through, a new bend or length of conduit shall be installed at the points of obstruction. 7. Ends of conduits shall be plugged to prevent the entrance of concrete, sand or other foreign material. As soon as practical after forms are stripped, conduit runs shall be remandrelled and swabbed clean with dry rags. If the mandrel fails to pass, a new conduit shall be installed as a replacement as near as possible to the abandoned conduit. When conduit is clean and dry, plugs shall be replaced and left in place until wire or cable is pulled. Spare conduits shall remain plugged with pull lines left inside. D. After form removal, the inside of boxes, covers, and threads for attaching devices shall be cleaned of concrete and the conduit plugged unless cable is to be pulled immediately. 1. Exposed conduit runs shall be straight to the extent possible and shall be parallel with the lines of the room or wall surface where they are located unless otherwise directed. Exposed conduits shall N-10

8 be rigidly supported from the walls or structural members at intervals of not more than 5 feet unless otherwise directed. Appropriate anchors as specified in Section Materials and Workmanship shall be used. 2. Liquid-tight flexible metal conduit shall be used to make connections to equipment subject to vibration, noise transmission, or movement. Liquid-tight conduit 1-1/2 inches and larger shall be provided with a separate grounding conductor. Liquid-tight flexible conduit shall meet NEC requirements, but not exceed 6 feet in length at any location. 3. Seals shall be used where required. The sealing material shall be Graybar, Permagum; 3M, Scotchfill; or equal. E. Outlet and junction boxes shall be securely mounted to structures or masonry walls as shown. Additional supports between structure members shall be provided as required to correctly locate boxes. F. Wiring troughs shall be surface mounted with appropriate anchors as specified in Section Materials and Workmanship and 1/4 inch spacers to prevent contact between the back of equipment and block or concrete walls. G. Cables in pull boxes shall be supported by cable racks and secured to rack insulators. H. Not less than 12 inches of gravel shall be provided under the pull box for proper drainage. Where duct enters pull boxes, appropriate end bells shall be used. Empty conduits shall be plugged or capped with fittings standard for the type of duct used and labeled as approved. I. Pull boxes shall be 1.5 inches above grade in the roadways and 6 inches above grade elsewhere. J. Gravel: Gravel shall be well graded from 1/4 inch to 1-1/2 inches as specified in Section Aggregate Base. K. Installation: Ducts shall be buried in earth and shall be straight, without sags and shall have a minimum cover of 24 inches unless otherwise shown. Variations from the 24 inch minimum depth shall be approved prior to installation. L. Duct runs shall be straight and true between pull boxes. Bends shall not be used except where shown or approved. Where alignment curves are required, they shall be made by bending or angle segments N-10

9 M. Ducts shall begin to fan out from standard separation to that at the duct pull box entrance, at least 30 feet from the pull box, by gradual change in alignment at the coupling of each straight section. N. Minimum slope for duct runs shall be 2 inches per 100 feet. Double slope grading of ducts will be acceptable. Ducts shall slope toward pull box to avoid pockets. O. Anchorage shall be provided to prevent floating of conduits during placing of concrete. Method of anchoring shall be Contractor s standard. P. Horizontal and vertical separation between the conduits shall be maintained by installing spacers with horizontal and vertical locking interval at approximately 10 feet intervals. Q. Metal such as cable racks, pulling irons, located in the concrete pull boxes shall be permanently and effectively grounded by means of a number 4 AWG bare copper ground wire connected to the duct bank ground cable. A grounding conductor shall be embedded in the concrete duct banks throughout the length of the system and shall be sized as shown FIELD QUALITY CONTROL A. Conduits shall be measured after being installed, and the actual lengths shall be entered on the conduit schedules, and a completed copy of the schedules shall be furnished to the Engineer. B. Buried or embedded conduits shall not be covered until inspected by the Engineer. PART 4 PAYMENT 4.01 PAYMENT A. The contract price will be paid for RACEWAYS AND BOXES; which price shall include full compensation for all costs incurred under this section. END OF SECTION N-10