HOUSTON COMMUNITY COLLEGE HCC ALIEF CAMPUS MAIN BUILDING, FIRST, SECOND & FOURTH FLOORS RENOVATION ISSUE DATE:

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1 SECTION GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEMS PART 1 - GENERAL 1.1 SUMMARY A. This Section includes grounding and bonding products, design requirements and installation for communications systems. B. Related Sections include: 1. Section Conduits and Pull Boxes for Communications Systems 2. Section Cable Tray and Runway for Communications Systems 3. Section Communications Room Fittings 4. Section Communications Backbone Cabling and Terminations 1.2 REFERENCES A. The publications listed below form a part of this specification. The publications are referred to in the text by basic designation only. B. Specific reference in specifications to codes, rules, regulations, standards, manufacturer s instructions, or requirements of regulatory agencies shall mean the latest printed edition of each in effect at the date of contract unless the document is shown dated. C. Conflicts: 1. Between referenced requirements: Comply with the one establishing the more stringent requirements. 2. Between referenced requirements and contract documents: Comply with the one establishing the more stringent requirements. D. References: 1. American Society for Testing and Materials (ASTM): a. B 3 Soft or Annealed Copper Wires b. B 8 Concentric-Lay-Stranded Copper Conductors, Hard, Medium Hard, Soft c. B 33 Tinned Soft or Annealed Copper Wire for Electrical Purposes 2. Institute of Electrical and Electronics Engineers (IEEE): a. IEEE 142Recommended Practice for Grounding of Industrial and Commercial Power Systems b. IEEE IEEE Standard for Type Test of Class IE Electric Cables, Field Splices, and Connections for Nuclear Power Generating Stations c. IEEE Recommended Practice for Powering and Grounding Sensitive Electronic Equipment in Industrial and Commercial Power Systems GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

2 3. Underwriters' Laboratories (UL): a. UL 83 Thermoplastic Insulated Wire and Cables b. UL 96 Lightning Protection Components c. UL 96A Installation Requirements for Lightning Protection Systems d. UL 467 Grounding and Bonding Equipment 4. National Fire Protection Association (NFPA): a. ANSI/NFPA 780 Lightning Protection Code b. ANSI/NFPA 70 National Electrical Code (NEC) 1) NEC Article No. 250 Grounding 2) NEC Chapter 8 Communications Systems 5. ANSI/TIA/EIA-607 Commercial Building Grounding and Bonding Requirements for Telecommunications 6. Building Industry Consulting Services International (BICSI) Telecommunications Distribution Methods Manual (TDMM) 7. Local, county, state and federal regulations and codes in effect as of date of purchase 8. Equipment of foreign manufacture must meet U.S. codes and standards. It shall be indicated in the proposal the components that may be of foreign manufacture, if any, and the country of origin. 1.3 SUBMITTALS A. Qualifications: Demonstrate compliance with requirements of Paragraph 1.4.A below. B. Product Data: Manufacturers catalog data, installation procedures and instructions for handling and storage. C. Record Drawings: Furnish as built CAD drawings of completed work. 1.4 QUALITY ASSURANCE A. Contractor Qualifications. Submit written proof that the following experience requirements are being met. 1. The Contractor shall submit references and other related evidence of installation experience for a period of three years prior to the issue date of this Specification. 2. All work shall be supervised on-site by a BICSI Registered Communications Distribution Designer (RCDD) who shall demonstrate knowledge and compliance with all BICSI, TIA/EIA, UL, and NEC standards and codes. Contractor shall submit proof of RCDD designation. B. Furnish products of latest proven design, new and in current production. Do not use obsolete components or out-of-production products. C. Tests for Insulated Cable: Pass vertical tray flame test following IEEE DESIGN REQUIREMENTS GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

3 A. Design grounding system following NEC Article No Grounding, IEEE Recommended Practice for Grounding of Industrial and Commercial Power Systems and BICSI TDMM, by a firm acceptable to owner's insurance underwriter. B. Design Standards: 1. Completely protect above-surface structures and equipment. 2. Calculate system on the basis of existing soil resistivity. 3. If cathodic protection for underground sewer pipe is installed (see applicable Division 2 Sections), ensure the pipe is not connected to the general grounding system, either directly through grounding cable or indirectly through grounded electrical devices connected to the pipe. Electrically isolate electrical devices from sewer pipe. 1.6 DELIVERY AND STORAGE A. Ship on manufacturer's standard reel sizes of one continuous length. Where cut lengths are specified, mark reel quantity accordingly. B. Protect wire wood lagging or suitable barrier across the traverse of reels. Provide heat-shrink self-sealing end caps on cable. PART 2 - PRODUCTS 2.1 MANUFACTURERS A. Subject to compliance with requirements, manufacturers that may be incorporated in the work, include, but are not limited to the following: B. Cable Manufacturers 1. Houston Wire and Cable Company 2. Okonite Company 3. General Cable 4. Pirelli Cable Corporation 5. Triangle Wire and Cable, Inc C. Ground Rod And Connector Manufacturers 1. Copperweld 2. Thomas & Betts 3. Blackburn D. Exothermic Connector Manufacturers 1. Erico Products (Cadweld) 2. Continental Industries (thermoweld) GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

4 E. Grounding Connector Manufacturers 1. Thomas & Betts 2. FCI Burndy Electrical 3. O-Z/Gedney 2.2 MATERIALS HOUSTON COMMUNITY COLLEGE A. Communications Grounding Conductors: Insulated copper American Wire Gauge (AWG) wire following ASTM-B3, ASTM-B8 and ASTM-B33, of following sizes: 1. Main ground source feed from the building ground system to the Telecommunications Main Ground Busbar (TMGB): No. 3/0 AWG green insulated stranded copper ground wire. 2. Telecommunications Bonding Backbone (TBB), from the TMGB to the Telecommunications Ground Busbars (TGB): No. 3/0 AWG green insulated stranded copper ground wire. 3. TGB to equipment cabinets and racks, conduits, cable raceways, etc.: No. 6 AWG green insulated stranded copper ground wire. B. Grounding Connectors: Connectors shall be a copper alloy material and two-hole compression lug type at all connecting ends. C. Grounding Rods: A minimum of ten feet long, 3/4-inch diameter, copper-clad steel. D. Telecommunications Main Ground Busbar: The TMGB, located in the main distribution facility (MDF), shall comply with the following: 1. Predrilled copper busbar with standard NEMA bolt hole sizing and spacing for the type of connectors to be used. 2. Sized for the immediate requirements and allow for growth. The minimum dimensions shall be ¼ inch thick by 4 inches wide by 23 inches long. 3. Electrotin plated for reduced contact resistance. 4. Contain pre-drilled holes, which shall support a minimum of two tiers of eight No. 6 AWG copper two-hole compression lugs. 5. ASTM-B187-C11000 Copper bar suitable for use with two-hole compression-type copper lugs. E. Telecommunications Ground Busbars: Each TGB, located in each communications room, shall comply with the following: 1. Predrilled copper busbar with standard NEMA bolthole sizing and spacing for the type of connectors to be used. 2. Sized for the immediate requirements and allow for growth. The minimum dimensions shall be ¼ inch thick by 4 inches wide by 23 inches long. 3. Electrotin plated for reduced contact resistance. GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

5 4. Pre-drilled holes, which shall support a minimum of two tiers of eight No. 6 AWG twohole copper compression lugs. 5. ASTM-B187-C11000 Copper bar suitable for use with two-hole compression-type copper lugs. F. Equipment Cabinet and Rack Ground Busbar 1. Provide and install a ground busbar in all racks and equipment cabinets to be used as an equipment grounding bus. 2. The busbar shall be for equal-flange (channel) 19-inch rack width and shall include ground bar, splice plate and #12-24 mounting hardware. 3. The minimum dimensions shall be ¾ inch in width by 3/16 inch in thickness. 4. The busbar shall have pre-drilled holes, which shall support a minimum of eight No. 6 AWG two-hole copper compression lugs. 5. The busbar shall be suitable for use with two-hole compression-type copper lugs. 2.3 SYSTEM REQUIREMENTS A. General 1. All conductor wire, busbars and conduit shall be UL listed. 2. The communications ground system shall be independent from all power grounding. 3. Power grounding and/or bonding shall not be allowed to interfere or provide any back feed or be a conductor to the separate communications ground system source or to any communications bonded materials or equipment. B. TMGB 1. The main ground source feed to the TMGB in the MDF shall be an independent feed from the main building ground system. 2. The main ground source feed shall be a No. 3/0 AWG green insulated stranded copper ground wire from the building ground system to the TMGB in the MDF. 3. The No. 3/0 AWG green insulated stranded copper ground wire shall be installed in a two-inch metallic conduit. 4. The No. 3/0 AWG green insulated stranded copper ground wire connections shall be exothermically welded at connecting ends. C. TBB and TGB 1. The TBB originates at the TMGB and shall be extended from the TMGB to each TGB within the MDF and throughout the building using the telecommunications backbone pathways, to the TGB(s) in each IDF. The minimum TBB conductor size shall be a No. 3/0 AWG green insulated stranded copper ground wire. The TBB shall be installed in a two-inch metallic conduit. 2. The TBB No. 3/0 AWG green insulated stranded copper ground wire connections shall be exothermically welded at connecting ends. GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

6 D. Equipment cabinets and racks. All cabinets and racks shall be provided with a separate communications ground, consisting of a No. 6 AWG green insulated stranded copper ground wire, from the nearest TGB in the room and home run to each cabinet or rack ground busbar. PART 3 - EXECUTION 3.1 EXAMINATION A. Field Measurements: Verify dimensions in areas of installation by field measurements before fabrication and indicate measurements on shop drawings. Coordinate fabrication schedule with construction progress to avoid delaying the work. B. Established Dimensions: Where field measurements cannot be made without delaying the work, establish dimensions and proceed with fabricating units without field measurements. Coordinate supports, adjacent construction, and fixture locations to ensure actual dimensions correspond to established dimensions. 3.2 PREPARATION A. Contractor s on-site RCDD supervisor shall review, approve and stamp all shop drawings, coordination drawings and record drawings. B. Copper and copper alloy connections should be cleaned prior to connection. 3.3 INSTALLATION A. Install work following drawings, manufacturer s instructions and approved submittal data. B. Installation plans and requests for information (RFIs) shall be reviewed by contractor s on-site RCDD. C. All work shall be supervised and reviewed by contractor s on-site RCDD. D. General 1. Bonding conductors shall be routed with minimum bends or changes in direction and should be made directly to the points being bonded. 2. Bonding connections should be made by using compression copper lugs or, within the ground electrode system, exothermic welding (see NEC Article 250) for parts of a grounding system that are subject to corrosion, that must carry high currents reliably or for locations that require minimum maintenance. 3. Make connections to dry surfaces only. Remove paint, rust, oxides, scales, grease and dirt from surfaces before making connection. Sand clean a one square inch area, drill, tap, and bolt conductor and connector to sanded area. Ensure proper conductivity. 4. The No. 3/0 AWG insulated ground wire weld ends shall have a minimum amount of wire exposure from the conduit to each weld and a minimum amount of insulation removed at weld. GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

7 5. The No. 6 AWG insulated ground wire connecting ends shall have a minimum amount of insulation removed at ground lug. 6. Do not connect ground wire in power cable assemblies to the communications ground system. E. Equipment Cabinets and Racks 1. The busbar shall be installed at the base and back of each cabinet and rack. 2. Each cabinet and rack shall be provided with a No. 6 AWG insulated ground wire home run to the TGB. 3. Do not loop from cabinet/rack to cabinet/rack. 4. Each cabinet or rack bay against the wall shall be bottom/side ground feeds from the wall. a. Wall ground feeds/raceways to racks shall not be exposed on the walls. b. Exception: Some cabinet or rack bays will require the ground to be fed from the ceiling raceway. Refer to drawings for details. 5. All ground raceways within each cabinet (or on each rack, where applicable) or cabinet base and adjacent ganged cabinet base shall be an insulated metallic flex type raceway and shall not interfere with equipment mounting framing or equipment mounting brackets. 6. Each ground feed shall provide proper installation allowances and penetration depths to provide conversion fittings from solid metallic to insulated metallic flex conduit raceways. 7. To bond each cabinet and rack to ground, sand clean a one square inch area, drill, tap, and bolt conductor and connector to sanded area. F. Cable Runway, Cable Raceway And Support System Grounding 1. Provide communications cable tray and cable runway systems with a communications isolated ground from the nearest TGB. 2. Provide and install No. 6 AWG insulated ground wire to one end of each cable tray/runway system and home run to nearest TGB. 3. Communications cable tray/runway that is located in the same room as the TMGB shall be connected to the TMGB. 4. Provide grounding path between cable tray/runway sections with grounding strap. 5. For electrically non-continuous conduits which contain only a grounding conductor, bond the conduit and conductor together at both ends to ground. 6. Bond conduit ends to nearest TGB with grounding bushings or ground clamps G. Shielded Backbone Cabling: Terminate and bond shield to the nearest TGB or TMGB at both ends, following manufacturer s guidelines. H. Unshielded Backbone Cabling: 1. Route a No. 6 AWG copper ground wire along each backbone cable route. 2. Bond each end at the nearest TGB or TMGB in the area that the associated cables are terminated. GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM

8 3.4 TESTING A. Upon completion of the electrical system, including all grounding, the Electrical Contractor shall test the system for stray currents, ground shorts, etc. Approved instruments, apparatus, services, and qualified personnel shall be utilized. If stray currents, shorts, etc., are detected, eliminate or correct as required. END OF SECTION GROUNDING AND BONDING FOR COMMUNICATIONS SYSTEM