1、09-10 26 18 41 - 1 SECTION 26 18 41 MEDIUM-VOLTAGE SWITCHES SPEC WRITER NOTE: Delete between /-/ if not applicable to project. Also delete any other item or paragraph not applicable to the section and renumber the paragraphs. PART 1 - GENERAL 1.1 DESCRIPTION This section specifies the furnishing, in
2、stallation and connection of medium voltage switches. 1.2 RELATED WORK A. Section 09 06 00, SCHEDULE FOR FINISHES: Switch finishes. /B. Section 13 05 41, SEISMIC RESTRAINT REQUIREMENTS FOR NON-STRUCTURAL COMPONENTS: Requirement for seismic restraint for nonstructural Components./ /C. Section 25 10 1
3、0, ADVANCED UTILITY METERING: Electricity meters installed in medium voltage switches./ D. Section 26 05 11, REQUIREMENTS FOR ELECTRICAL INSTALLATIONS: General electrical requirements that are common to more that one section of Division 26. E. Section 26 05 13, MEDIUM-VOLTAGE CABLES: Medium voltage
4、cables and splices. F. Section 26 05 26, GROUNDING AND BONDING FOR ELECTRICAL SYSTEMS: Requirements for personnel safety and to provide a low impedance path to ground for possible ground fault currents. G. Section 26 05 71, ELECTRICAL SYSTEM PROTECTIVE DEVICE STUDY: Short circuit and coordination st
5、udy. 1.3 QUALITY ASSURANCE Refer to Paragraph, QUALIFICATIONS, in Section 26 05 11, REQUIREMENTS FOR ELECTRICAL INSTALLATIONS. 1.4 FACTORY TESTS A. Medium voltage switches shall be thoroughly tested at the factory to assure that there are no electrical or mechanical defects. Tests shall be conducted
6、 as per UL and ANSI Standards. Factory tests shall be certified. The following tests shall be performed: 1. Verify that fuse sizes and types are in accordance with drawings and coordination study. 2. Verify tightness of bolted electrical connections by calibrated torque-wrench method in accordance w
7、ith manufacturers published data. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-09-10 26 18 41 - 2 3. Verify operation and sequencing of interlocking systems. 4. Verify correct phase barrier installation. 5. Verify correct operation of all indicati
8、ng and control devices. 6. Verify appropriate lubrication on moving current-carrying parts and on moving and sliding surfaces. 7. Exercise all active components. 8. Perform insulation-resistance tests on each pole, phase-to-phase and phase-to-ground with switch closed, and across each open pole. App
9、ly voltage in accordance with manufacturers published data. 9. Perform a dielectric withstand voltage test on each pole with switch closed. Test each pole-to-ground with all other poles grounded. Test voltage shall be in accordance with manufacturers published data. B. Furnish four (4) copies of cer
10、tified manufacturers factory test reports to the Resident Engineer prior to shipment of the switches to ensure that the switches have been successfully tested as specified. /C. The Government shall have an option to witness the factory tests. All expenses of the Government Representatives trips to w
11、itness the testing will be paid by the Government. Notify the Resident Engineer not less than 30 days prior to making tests at the factory./ 1.5 SUBMITTALS A. In accordance with Section 26 05 11, REQUIREMENTS FOR ELECTRICAL INSTALLATIONS, submit the following: B. Shop Drawings: 1. Provide detailed d
12、rawings with sufficient information, clearly presented, to determine compliance with drawings and specifications. 2. Provide information such as complete electrical ratings, dimensions and approximate design weights, mounting details, materials, required clearances, cable terminations, fuse sizes an
13、d class, interrupting ratings, wiring and connection diagrams, front, side and rear elevations, sectional views, safety features, accessories and nameplate data. C. Manuals: 1. Submit, simultaneously with the shop drawings, companion copies of complete maintenance and operating manuals including tec
14、hnical data sheets, wiring diagrams and information for ordering replacement parts. 2. Two weeks prior to the project final inspection, submit four copies of the final updated maintenance and operating manuals to the Resident Engineer. (Update the manuals to include any revisions necessitated by sho
15、p drawing approval). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-09-10 26 18 41 - 3 D. Certification: Two weeks prior to final inspection, submit four copies of the following to the /Resident Engineer/ /COTR/: SPEC WRITER NOTE: Refer to VA Handbo
16、ok H-18-8 for Seismic Design Requirements. Specify Region of Seismicity, based on location of the equipment so motor control center manufacturers can check/design seismic strength of their equipment. Delete the following paragraph if the motor control center(s) is located outside the seismic zone. /
17、1. Certification from the manufacturer that the switches will withstand the seismic forces and that the unit will be fully operational after the seismic event at the project site./ 2. Certification by the manufacturer that the materials conform to the requirements of the drawings and specifications.
18、 3. Certification by the Contractor that the materials have been properly installed, adjusted, and tested. 1.6 APPLICABLE PUBLICATIONS A. Publications listed below (including amendments, addenda, revisions, supplements, and errata) form a part of this specification to the extent referenced. Publicat
19、ions are referenced in the text by designation only. B. American National Standards Institute (ANSI): C37.47 . Medium voltage Current-Limiting Type Distribution Class Fuses and Fuse Disconnect Switches C37.58 . Conformance Test Procedures for Indoor AC Medium-Voltage Switches for Use in Metal-Enclos
20、ed Switchgear C. Institute of Electrical and Electronics Engineers (IEEE): C37.20.3 . Metal-Enclosed Interrupter Switchgear C37.48 . Guide for Application, Operation and Maintenance of Medium voltage Fuses, Distribution Enclosed Single Pole Air Switches, Fuse Disconnecting Switches and Accessories D
21、. National Electrical Manufacturers Association (NEMA): C37.22 . Preferred Ratings and Required Capabilities for Indoor AC Medium-Voltage Switches Used in Metal-Enclosed Switchgear SG 6 . Power Switching Equipment E. National Fire Protection Association (NFPA): 70 . National Electrical Code (NEC) Pr
22、ovided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-09-10 26 18 41 - 4 PART 2 - PRODUCTS 2.1 MEDIUM VOLTAGE AIR BREAK SWITCHES A. Shall be in accordance with ANSI, IEEE, NEMA, NFPA, as shown on the drawings and have the following features: 1. Deadfront air
23、 break, three-pole gang-operated, rated load interrupter type, with manual stored energy operator. 2. Copper blades. 3. A separate door for the fuse section. A mechanical interlock shall prevent opening the door unless the switch blades are open, and prevent closing the switch if the door is open. 4
24、. Phase barriers for the full length of the blades and fuses for each pole. 5. Protective shield to cover the cable connections on the line terminals. 6. Quick-make, quick-break, stored energy type operation mechanism. The mechanism shall enable the switch to close against a fault equal to the momen
25、tary rating of the switch without affecting its continuous current carrying or load interrupting ability. 7. External manual operating handle with lock-open padlocking provisions. 8. When the switches are open, the fuses shall be de-energized. 9. Current limiting, power type fuses. /10. Provision fo
26、r remote electrical operation./ 11. Enclosures: a. NEMA type shown on the drawings for the switches. Where the types of switch enclosures are not shown, they shall be the NEMA types which are most suitable for the environmental conditions where the switches are being installed. b. Doors: 1) Conceale
27、d or semi-concealed hinges shall be used to attach doors. Weld hinges to the enclosure and door. 2) Mechanically interlocked to prevent opening unless the switch blades are open. 3) Three point door locking mechanism, suitable handles and padlocking provisions. 4) Safety-glass window for viewing the
28、 switch blades. 5) Door stops for the open position. c. Finish: 1) All metal surfaces shall be thoroughly cleaned, phosphatized, primed and painted at the factory. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-09-10 26 18 41 - 5 2) Final finish sha
29、ll be enamel, lacquer or powder coating. Enamel and powder coatings shall be oven baked. Color shall be light gray. B. Minimum switch fault close and momentary current rating shall be /40 / 60 / 80 / kA with a 2 second current rating of / 25 / 38 / 50 /kA. /2.2 METERING Refer to Section 25 10 10, AD
30、VANCED UTILITY METERING./ 2.3 NAMEPLATES AND MIMIC BUS A. Nameplates: For Normal Power system, provide laminated black phenolic resin with white core with 1/2 inch 12mm engraved lettered nameplates next to each switch. For Essential Electrical System, provide laminated red phenolic resin with white
31、core with 1/2 inch 12mm engraved lettered nameplates next to each switch. Nameplates shall indicate equipment served, spaces, or spares in accordance with one line diagram shown on drawings. Nameplates shall be mounted with plated screws on front of switches. Mounting nameplates only with adhesive i
32、s not acceptable. B. Mimic Bus: Provide an approved mimic bus on front of each switch assembly. Color shall be black for the Normal Power system and red for the Essential Electrical System, either factory-painted plastic or metal strips. Plastic tape shall not be used. Use symbols similar to one lin
33、e diagram shown on drawings. Plastic or metal strips shall be mounted with plated screws. PART 3 - EXECUTION 3.1 INSTALLATION A. Install the switches in accordance with the NEC, manufacturers instructions and recommendations and as shown on the drawings. B. Anchor the units with rustproof bolts, nut
34、s and washers not less than 1/2-inch 13mm diameter. /B. In seismic areas, equipment shall be adequately anchored and braced per details on structural contract drawings to withstand the seismic forces at the location where installed./ SPEC WRITER NOTE: Mounting slab connections may have to be given i
35、n detail depending on the requirements for the seismic zone in which the equipment is located. Include construction requirements for concrete slab only if slab is not detailed in drawings. C. Exterior Location. Mount switches on concrete slab. Unless otherwise indicated, the slab shall be at least 8
36、 inches 200mm thick, reinforced with a 6 by 6 inch 150 by 150 mm No. 6 mesh placed uniformly 4 inches Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-09-10 26 18 41 - 6 100mm from the top of the slab. Slab shall be placed on a 6 inch 150mm thick, wel
37、l-compacted gravel base. The top of the concrete slab shall be approximately 4 inches 100mm above the finished grade. Edges above grade shall have 1/2 inch 15mm chamfer. The slab shall be of adequate size to project at least 8 inches 200mm beyond the equipment. Provide conduit turnups and cable entr
38、ance space required by the equipment to be mounted. Seal voids around conduit openings in slab with water- and oil-resistant caulking or sealant. Cut off and bush conduits 3 inches 75mm above slab surface. Concrete work shall be as specified in Section 03 30 00, CAST-IN-PLACE CONCRETE. D. Interior L
39、ocation. Mount switches on concrete slab. Unless otherwise indicated, the slab shall be at least 4 inches 100mm thick. The top of the concrete slab shall be approximately 4 inches 100mm above finished floor. Edges above floor shall have 1/2 inch 15mm chamfer. The slab shall be of adequate size to pr
40、oject at least 100 mm 8 inches beyond the equipment. Provide conduit turnups and cable entrance space required by the equipment to be mounted. Seal voids around conduit openings in slab with water- and oil-resistant caulking or sealant. Cut off and bush conduits 3 inches 75mm above slab surface. Con
41、crete work shall be as specified in Section 03 30 00, CAST-IN-PLACE CONCRETE. 3.2 ACCEPTANCE CHECKS AND TESTS A. Perform in accordance with the manufacturers recommendations. Include the following visual and mechanical inspections: 1. Compare equipment nameplate data with specifications and approved
42、 shop drawings. 2. Inspect physical and mechanical condition. 3. Confirm correct application of manufacturers recommended lubricants. 4. Clean switches. 5. Verify appropriate anchorage and required area clearances. 6. Verify appropriate equipment grounding. 7. Verify correct blade alignment, blade p
43、enetration, travel stops, and mechanical operation. /8. Verify that fuse sizes and types correspond to approved shop drawings./ 9. Inspect all field-installed bolted electrical connections, verifying tightness of accessible bolted electrical connections by calibrated torque-wrench method, or perform
44、ing thermographic survey after energization under load. 10. Exercise all active components. 11. Test interlocking systems for correct operation and sequencing. 12. Inspect all indicating devices for correct operation. Provided by IHSNot for ResaleNo reproduction or networking permitted without licen
45、se from IHS-,-,-09-10 26 18 41 - 7 3.3 FOLLOW-UP VERIFICATION Upon completion of acceptance checks, settings, and tests, the Contractor shall show by demonstration in service that switches are in good operating condition and properly performing the intended function. 3.4 SPARE PARTS Two weeks prior
46、to the final inspection, provide one (1) set of spare fuses for each fused switch installed on this project. 3.5 INSTRUCTION Furnish the services of a factory certified instructor for one 4 hour period for instructing personnel in the operation and maintenance of the switchgear and related equipment on the date requested by the Resident Engineer. - - - E N D - - - Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
