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HomeMy WebLinkAbout16060.pdf BICKFORD OF CARMEL, IN 12/12/2012 GROUNDING AND BONDING 16060 - 1 SECTION 16060 - GROUNDING AND BONDING PART 1 - GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section. 1.2 SUMMARY A. This Section includes methods and materials for grounding systems and equipment. 1.3 SUBMITTALS A. Product Data: For each type of product indicated. 1.4 QUALITY ASSURANCE A. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, Article 100, by a testing agency acceptable to authorities having jurisdiction, and marked for intended use. B. Comply with UL 467 for grounding and bonding materials and equipment. PART 2 - PRODUCTS 2.1 CONDUCTORS A. Insulated Conductors: Copper wire or cable insulated for 600 V unless otherwise required by applicable Code or authorities having jurisdiction. B. Bare Copper Conductors: 1. Solid Conductors: ASTM B 3. 2. Stranded Conductors: ASTM B 8. 3. Tinned Conductors: ASTM B 33. 4. Bonding Cable: 28 kcmil, 14 strands of No. 17 AWG conductor, 1/4 inch in diameter. 5. Bonding Conductor: No. 4 or No. 6 AWG, stranded conductor. 6. Bonding Jumper: Copper tape, braided conductors, terminated with copper ferrules; 1- 5/8 inches wide and 1/16 inch thick. 7. Tinned Bonding Jumper: Tinned-copper tape, braided conductors, terminated with copper ferrules; 1-5/8 inches wide and 1/16 inch thick. BICKFORD OF CARMEL, IN 12/12/2012 GROUNDING AND BONDING 16060 - 2 C. Bare Grounding Conductor and Conductor Protector for Wood Poles: 1. No. 4 AWG minimum, soft-drawn copper. 2. Conductor Protector: Half-round PVC or wood molding. If wood, use pressure-treated fir or cypress or cedar. D. Grounding Bus: Rectangular bars of annealed copper, 1/4 by 2 inches in cross section, unless otherwise indicated; with insulators. 2.2 CONNECTORS A. Listed and labeled by a nationally recognized testing laboratory acceptable to authorities having jurisdiction for applications in which used, and for specific types, sizes, and combinations of conductors and other items connected. B. Bolted Connectors for Conductors and Pipes: Copper or copper alloy, bolted pressure-type, with at least two bolts. 1. Pipe Connectors: Clamp type, sized for pipe. C. Welded Connectors: Exothermic-welding kits of types recommended by kit manufacturer for materials being joined and installation conditions. 2.3 GROUNDING ELECTRODES A. Ground Rods: Copper-clad steel; 3/4 inch by10 feet in diameter. PART 3 - EXECUTION 3.1 APPLICATIONS A. Conductors: Install solid conductor for No. 8 AWG and smaller, and stranded conductors for No. 6 AWG and larger, unless otherwise indicated. B. Grounding Bus: Install in electrical and telephone equipment rooms (Tech Rooms and Wiring Closet), in rooms housing service equipment, and elsewhere as indicated. 1. Install bus on insulated spacers 1 inch, minimum, from wall 6 inches above finished floor, unless otherwise indicated. 2. Where indicated on both sides of doorways, route bus up to top of door frame, across top of doorway, down to specified height above floor, and connect to horizontal bus. C. Conductor Terminations and Connections: 1. Pipe and Equipment Grounding Conductor Terminations: Bolted connectors. 2. Connections to Structural Steel: Welded connectors. BICKFORD OF CARMEL, IN 12/12/2012 GROUNDING AND BONDING 16060 - 3 3.2 EQUIPMENT GROUNDING A. Install insulated equipment grounding conductors with all feeders and branch circuits. B. Install insulated equipment grounding conductors with the following items, in addition to those required by NFPA 70: 1. Feeders and branch circuits. 2. Lighting circuits. 3. Receptacle circuits. 4. Single-phase motor and appliance branch circuits. 5. Three-phase motor and appliance branch circuits. 6. Flexible raceway runs. 7. Computer and Rack-Mounted Electronic Equipment Circuits: Install insulated equipment grounding conductor in branch-circuit runs from equipment-area power panels and power-distribution units. C. Air-Duct Equipment Circuits: Install insulated equipment grounding conductor to duct- mounted electrical devices operating at 120 V and more, including air cleaners, heaters, dampers, humidifiers, and other duct electrical equipment. Bond conductor to each unit and to air duct and connected metallic piping. D. Signal and Communication Equipment: For telephone, alarm, voice and data, and other communication equipment, provide No. 4 AWG minimum insulated grounding conductor in raceway from grounding electrode system to each service location, terminal cabinet, wiring closet, and central equipment location. 1. Service and Central Equipment Locations and Wiring Closets: Terminate grounding conductor on a 1/4-by-2-by-12-inch grounding bus. 2. Terminal Cabinets: Terminate grounding conductor on cabinet grounding terminal. 3.3 INSTALLATION A. Grounding Conductors: Route along shortest and straightest paths possible, unless otherwise indicated or required by Code. Avoid obstructing access or placing conductors where they may be subjected to strain, impact, or damage. B. Ground Rods: Drive rods until tops are 2 inches below finished floor or final grade, unless otherwise indicated. 1. Interconnect ground rods with grounding electrode conductor below grade and as otherwise indicated. Make connections without exposing steel or damaging coating, if any. 2. For grounding electrode system, install at least three rods spaced at least one-rod length from each other and located at least the same distance from other grounding electrodes, and connect to the service grounding electrode conductor. C. Bonding Straps and Jumpers: Install in locations accessible for inspection and maintenance, except where routed through short lengths of conduit. BICKFORD OF CARMEL, IN 12/12/2012 GROUNDING AND BONDING 16060 - 4 1. Bonding to Structure: Bond straps directly to basic structure, taking care not to penetrate any adjacent parts. 2. Bonding to Equipment Mounted on Vibration Isolation Hangers and Supports: Install so vibration is not transmitted to rigidly mounted equipment. 3. Use exothermic-welded connectors for outdoor locations, but if a disconnect-type connection is required, use a bolted clamp. D. Grounding and Bonding for Piping: 1. Metal Water Service Pipe: Install insulated copper grounding conductors, in conduit, from building's main service equipment, or grounding bus, to main metal water service entrances to building. Connect grounding conductors to main metal water service pipes, using a bolted clamp connector or by bolting a lug-type connector to a pipe flange, using one of the lug bolts of the flange. Where a dielectric main water fitting is installed, connect grounding conductor on street side of fitting. Bond metal grounding conductor conduit or sleeve to conductor at each end. 2. Water Meter Piping: Use braided-type bonding jumpers to electrically bypass water meters. Connect to pipe with a bolted connector. 3. Bond each aboveground portion of gas piping system downstream from equipment shutoff valve. E. Bonding Interior Metal Ducts: Bond metal air ducts to equipment grounding conductors of associated fans, blowers, electric heaters, and air cleaners. Install bonding jumper to bond across flexible duct connections to achieve continuity. F. Grounding and Bonding for Building or Structure: 1. Provide grounding connections to rebar and building steel as required by NEC. 2. Provide concrete-encased electrode as required by NEC and local authorities. 3.4 FIELD QUALITY CONTROL A. Testing Agency: Owner will engage qualified testing and inspecting personnel to perform field tests and inspections and prepare test reports. B. Perform the following tests and inspections and prepare test reports: 1. After installing grounding system but before permanent electrical circuits have been energized, test for compliance with requirements. C. Report measured ground resistances that exceed the following values: 1. Power and Lighting Equipment or System with Capacity 500 kVA and Less: 10 ohms. D. Excessive Ground Resistance: If resistance to ground exceeds specified values, notify Architect promptly and include recommendations to reduce ground resistance. END OF SECTION 16060