A. This Section includes Low Voltage Switchgear Work, as indicated on the drawings, and as specified herein.

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1 16425 SWITCHBOARD ************************************************************************************************************* SPECIFIER: CSI MasterFormat 2004 number: An optional keynote to the Drawings follows major product titles, for A/Es using National CAD Standard. ************************************************************************************************************* PART 1 GENERAL 1.1 SUMMARY A. This Section includes Low Voltage Switchgear Work, as indicated on the drawings, and as specified herein. B. Related Work Grounding Wire, Cable and Splices Circuit Breakers Surge Protective Devices. 1.2 QUALITY ASSURANCE A. All materials shall be tested and listed by An OSHA approved Nationally Recognized Testing Laboratory (NRTL). B. Conform to the latest edition of the National Electrical Code and to requirements of applicable inspection authorities. 1.3 SUBMITTALS A. Submit manufacturer's literature and technical data. B. Submit Shop Drawings for switchboard: 1. Include dimensioned outline drawings, front elevation with location and identification of devices and instruments, bus duct connection details, conduit entrance locations, mounting and leveling instructions, device ratings and characteristics, main bus construction and location, main device key interlock details, ground fault connection diagram, and other details of construction. 2. Submit time-current coordination curves of main, tie and feeder devices. 3. Include details of the service bus ducts, including dimensioned outline drawings, ratings and installation details. 4. Provide coordination study of main breakers and sub-feeder breakers. C. Submit nameplate schedule for review. D. Submit shop drawings and product data under provisions of Section 01330, Submittals. Project No. SPECIFICATION GUIDELINES

2 PART 2 PRODUCTS 2.1 MANUFACTURERS A. Bus Ducts: 1. General Electric. 2. Siemens. 3. Square D. 2.2 INSTALLATION A. Furnish and install where indicated a dead front type, completely metal enclosed, selfsupporting structure independent of wall supports, consisting of the required number of vertical sections bolted together to form one rigid switchboard 90" high. The sides and rear shall be covered with removable screw-on plates. Edges of front covers or hinged front panels shall be formed. Voltage rating shall be as indicated on the drawings. 1. Service entrance switchboard shall be provided with individual and group fixed mounted over-current, disconnect devices, and additional features as required per associated electrical drawings. Assembly shall have NRTL listed Service Entrance Labeling. B. Equipment shall comply with the latest applicable standards of NEMA, ANSI, and UL. The switchboard shall be labeled for service entrance equipment. 1. The switchboard shall have a short circuit current rating to be equal or greater than the available short circuit current from the utility company, plus motor contributions. Switchboard assembly including all over current devices to be fully rated. No series ratings shall be permitted. 2. Future spaces: All unused spaces provided, unless otherwise specified, shall be fully equipped for future devices, including all appropriate connectors and mounting hardware. 3. Enclosure: a. Sections shall be aligned front and rear. b. Removable steel channels (1.5 floor sills) shall be bolted to the frame to rigidly support the entire switchboard during shipping c. Set the switchboard on a 4 concrete pad. d. All front covers shall be screw removable with a single tool and all doors be hinged with removable hinge pins. e. Top and bottom conduit areas shall be clearly indicated on shop drawings. 4. All Accessories and Features shall be provided as described per associated electrical drawings. 5. Provide terminations for incoming copper feeders from utility. Bus way shall be NRTL labeled and provide short circuit ratings equal to switchboard requirements. C. Small wiring, necessary fuse blocks, and terminal blocks within the switchboard shall be furnished as required. Groups of control wires leaving the switchboard shall be provided with terminal blocks with suitable numbering strips. Project No. SPECIFICATION GUIDELINES

3 1. Control power shall be provided via control power transformer with primary and secondary fuse protection, when integral components require 120 v or 24 vac power. D. Switchboard shall be provided with adequate lifting means and shall be capable of being rolled or moved into installation position and bolted directly to the floor without the use of floor sills. 1. Prepared spaces for all mounting hardware and bus connections. E. Exterior and interior steel surfaces of the switchboard shall be properly cleaned and finished with gray enamel over a rust-inhibiting phosphatic coating. Color shall be ANSI 61 gray. F. Engraved Nameplates: 1. Provide for main and feeder circuits including control fuses and for indicating lights and instruments. 2. Nameplates shall indicate item designation, circuit number, frame ampere size and appropriate trip rating. 3. Master Nameplate giving switchboard designation, voltage, ampere rating, short circuit rating, manufacturer's name, general order number, and item number. 4. Nameplates for each device shall be engraved laminated phenolic with black letters on a white backboard. G. Bus Bars: 1. Bus Bars shall be plated copper. Plating shall be applied continuously to all bus work. The switchboard bussing shall be sufficient cross sectional area shall meet UL Standard 891 temperature rise requirements. Neutral bus shall be equal to phase bus capacity. Tapered bus will not be acceptable. Full provisions for the addition of future sections shall be provided. 2. Ground Bus: sized per NFPA 70 (NEC) and UL: 891 and shall extend the entire length of the switchboard. 3. Bus work shall be rated to withstand maximum short circuit stresses when connected to a supply system having fault capacity as determined by the short circuit study on the electrical system in the worst contingency of 42,000 amps symmetrical at rated voltage. 4. Main horizontal bus bars shall be mounted with all three phases arranged in the same vertical plane. 5. Provide full capacity neutral where a neutral is indicated on the drawings. 6. Provide a ground bus and lug firmly secured to each vertical section structure and extending the entire length of the switchboard. 7. Provide ground lugs for each overcurrent device in the switchboard. 8. Hardware used on conductors shall be high-tensile strength and zinc plated. 9. Terminals shall be of the anti-turn solderless type suitable for CU or AL cable of sizes indicated. H. Provide cable pull sections or top cable pull boxes where shown on the drawings complete with cable tie down supports. Where cable pull section or pull boxes contain utility service cables provide utility accepted sealing means. Project No. SPECIFICATION GUIDELINES

4 I. Where spaces are indicated on the drawings, provide fully bussed sections ready to receive circuit breakers. Provide spaces for future expansion as indicated on drawings. J. Switchboard Type 1 (Front-Accessible Panel-Mounted): 1. Switchboards shown mounted against a wall shall be front accessible. All sections of the switchboard shall be 20 inches deep except deeper service sections containing large ampacity main disconnects. Sections of the switchboard shall align so the back of the complete structure may be placed flush against a wall. 2. Construction shall allow maintenance of incoming line terminations, main device connections, and main bus bolted connections to be performed without rear access. The feeder or branch devices shall be removable from the front and shall be panel mounted with the necessary device line and load connection front accessible. K. Overcurrent Protective Devices: 1. Main Circuit Breakers: a. Main protective devices shall be molded case type up to 1600 amperes, and insulated case type above 2000 amperes. 1) Breakers shall be NRTL labeled for application in their intended enclosure for 100 percent of their continuous ampere rating. 2) Frame ampere ratings shall be as shown on the drawings. Breakers shall have an interrupting capacity as determined by the short circuit study on the electrical system in the worst contingency and shall be rated 42,000 ka RMS symmetrical interrupting capacity at rated voltage. 3) Main Circuit Breakers shall be provided with electronic trip molded case circuit breakers through 2000 amp. Circuit breaker to be 100% duty rated. Adjustable time/current responses shall include longtime delay, short time delay, short time pick up, instantaneous, ground fault pick up and ground fault delay. b. Provide plug-in trip devices that are interchangeable between compatible breaker frames. 1) Suitable interlocking shall be provided between trip devices and related frames to ensure correct application. 2) The continuous ampere rating of the breaker shall be determined by the insertion of an interchangeable rating plug that matches the load and cable requirements. 3) The rating plug shall be interlocked with the tripping mechanism to automatically "open" the breaker when the plug is removed. 4) The breaker shall remain "trip free" with the plug removed. 5) Rating plugs shall be keyed to prevent incorrect application between different frame ratings. c. Complete system selective coordination shall be provided by the addition of the following time/ current curve shaping adjustments: 1) Ampere Setting.(Instantaneous) Project No. SPECIFICATION GUIDELINES

5 2) Long Time Delay. 3) Short Time Pick-Up (Only Mains) (Only Tie) (Only Feeders). 4) Short Time Delay. 5) Ground Fault Pick-Up, if applicable per NEC. 6) Ground Fault Time Delay, if applicable per NEC. d. Ground Fault Trip, when required by NEC: 1) Provide as an integral part of the breaker. 2) The ground fault pickup shall be adjustable with a maximum setting of 1200 amps according to the NEC requirements. 3) The time delay shall be adjustable in three discrete bands for maximum system selective coordination. 4) A memory circuit shall be provided to compensate for the erratic nature of arcing ground faults to provide for positive tripping actions. 5) A residual scheme shall be used as standard for detecting ground fault currents. e. A separately mounted test panel shall be provided for use with Pow-R Trip 7 trip devices. The test panel shall test the ground fault circuit in one of two methods. 1) By tripping the breaker. 2) By not tripping the breaker. 2. Feeder Circuit Breakers: a. Main and Feeder Protective Devices shall be provided with molded case air circuit breakers, built, tested, and NRTL labeled according to UL 489. b. Circuit breakers 125 amperes frame, Frames shall be thermal-magnetic trip with inverse time current characteristics. c. Circuit breakers above 125 amps shall have adjustable magnetic settings. For chiller loads, provide an electronic trip molded case circuit breaker with adjustable time/current responses such as long time pick up, long time delay, short time pick up, short time delay and instantaneous. d. Breakers 125 through 400 amperes: Provide continuously adjustable magnetic pickups of approximately five to ten times trip rating. e. Breakers 600 amperes frame and above: With solid-state trip complete with built in current transformers, and solid-state trip unit adjustable from 40 to 100 percent. 1) Breakers shall have easily changed trip rating plugs with trip ratings as indicated on drawings. 2) Rating plugs shall be interlocked so they are not interchangeable between frames. When interlocked, the breaker shall not be latched with rating plug removed. 3) Breaker shall have built-in test points for testing long delay and instantaneous and ground fault, where shown, functions of the breaker by means of a 120 volt operated test kit. 4) Provide one test kit capable of testing breakers 600 amperes and above. Project No. SPECIFICATION GUIDELINES

6 L. Meters: 5) Solid-state instantaneous element shall be continuously adjustable from approximately 4 to 8 times the trip rating, with short time adjustment from instantaneous to 10 cycle delay for coordination purposes. 6) Provide short delay override feature providing for instantaneous tripping on high magnitude faults. f. Where indicated on the drawings, provide optional adjustable trip rating plug approximately 70 to 100 percent of trip rating. Molded case breakers shall be determined by the short circuit study on the electrical system in the worst contingency and shall have a minimum 42,000 ka symmetrical RMS interrupting capacity at rated voltage. 1. LCD display front connected switchboard type with accuracy of +1 percent or better. 2. LCD meter shall have Ethernet ports for remote monitoring of third party software from a central location. 3. Provide the following customer metering equipment: a. Three single pole fuse blocks with current limiting fuses or as required by switchboard manufacturer. b. Meter selector push button(s). c. One voltmeter, 0-system volts per phase and average. d. One ammeter, scale as indicated, per phase and average. e. Power: real (KW) or reactive (KVAR). f. Energy (KWH). g. Set points and alarms. M. Service Bus Ducts: 1. Service bus ducts shall be in a steel housing, with individual bus bars insulated and supported over their entire lengths. Bars shall be copper silver plated at joints with at least 2 bolts per joint. Joint clamping bolts shall be "cold" and accessible for tightening at all times. 2. Vault stubs shall be constructed according to utility company standards. Coordinate location of stubs into vault with utility company. 3. Bus duct rating shall be of voltage and amperage as indicated, three-phase, fourwire. The bus duct rating shall be determined by the short circuit study on the electrical system in the worst contingency and shall be braced for the maximum available fault, in symmetrical amperes. 4. Provide switchboard with integral surge protection device as specified in Section Transient Voltage Surge Suppression. N. Provide lightning and surge protection. PART 3 EXECUTION 3.1 INSPECTION A. Do not proceed with the work of this section until conditions detrimental to the proper and timely completion of the work have been corrected in an acceptable manner. Project No. SPECIFICATION GUIDELINES

7 3.2 INSTALLATION A. Provide adequate and safe storage space for the switchboard when received from the factory. Follow handling and storage instructions provided by the manufacturer. Store in a clean, dry place while awaiting installation. B. Refer to the installation drawings furnished by the manufacturer to coordinate alignment and connection of service bus ducts and locations of conduit entry. Conduits shown on the floor slab and turning up under the bottom of the switchboard shall not be installed until final approved Shop Drawings are received, in order to coordinate conduit locations with openings in the bottom of the switchboard. This also applies to grounding cable turning up into the bottom of the switchboard. C. Steel conduits turning up under the bottom of the switchboard shall each be provided with a steel grounding bushing, connected to the switchboard ground bus with a stranded copper conductor sized according to the NEC. This shall also apply to steel conduits entering the switchboard from the top. Non-metallic duct entering the switchboard from the bottom shall each contain a stranded, THWN-2 copper bonding conductor, sized according to the NEC that shall be connected to the switchboard ground bus. Connections of bond wires to the switchboard ground bus shall be made with bolted compression lugs. D. The metal frame of the switchboard shall be connected to the switchboard ground bus, in at least 2 places, with stranded copper conductors of minimum 3/0 size. 1. Install equipment and make ground connections as indicated on the drawings. Ground lugs shall be required. 2. Test system after complete installation. E. Install switchboard in location shown on drawings. Mount on concrete housekeeping pad 4 inches high with an overlap of 4" all around the switchboard foot print. 1. Verify dimensions of equipment proposed with equipment outlined on drawings. 2. Level switchboards after installation. 3. Check all cable terminations for solid connection. F. Each device in the switchboard shall have phenolic nameplates, of dimensions and wording as shown on the drawings. Furnish black letters on a white background. G. After the switchboard is completely installed, but before energizing, the floor under the switchboard and the floor throughout the main switchgear room, shall be thoroughly cleaned. Remove dust, dirt, and debris. Thoroughly clean outside of switchboard including the top. Any factory paint damaged before, during, or after installation shall be repainted or touched up with same type and color paint. 1. Check all circuits for ground, shorts and continuity. 2. Test all breakers for operation. 3. Energize switchboard, test voltage. 4. After building is energized, test voltage and have Florida Power and Light Co. (FPL) set taps in transformer vault. H. Service bus ducts shall be installed from the utility company vault, through the wall and turn down into the top of the switchboard as detailed on drawings. Provide fire stop on Project No. SPECIFICATION GUIDELINES

8 each side of the wall around each bus duct. Provide careful alignment of the bus bars of the bus duct with the main bus of the switchboard. Insure the metal enclosure of each service bus duct is bonded to the metal enclosure of the switchboard. Fully coordinate, with utility company, proper phasing of bus bars in switchboard to comply with the NEC requirements. I. Provide grounding as indicated on the drawings. 1. Grounding shall conform to Section Roll ground rods to a commercially round shape from a welded copper-encased steel manufactured by the molten welding process or by the electro-formed process (molecularly bonded). a. The rods shall have a hard, clean, smooth continuous copper surface and the thickness of the copper shall be uniform throughout the length of the rod. b. The copper jacket shall have a minimum wall thickness of 0.20 inches. c. Ground rods be 3/4-inch diameter x 10 feet long minimum. 3. Provide a 4-inch x 4-inch minimum bare tinned copper ground collector bus in the main switchboard room. This ground collector bus shall be exothermic welded to the grounding system. 3.3 FIELD QUALITY CONTROL A. Provide time current curves as required for the coordination and setting adjustments for over current devices. B. Submit coordinating study to A/E and M-DCPS Project Manager, and maintain copy at construction trailer for review. C. Manufacturer's Field Service: A minimum of 1 day of manufacturer's factory engineering service shall be provided to lend technical assistance in setting circuit breaker trip settings. These settings shall include but not be limited to: 1. Ground Fault Setting. 2. Long Time Trip. END OF SECTION Project No. SPECIFICATION GUIDELINES