Low Voltage Switchgear

Specification Number: 26 23 xx.yy

Section Name: Arc Resistant Low Voltage Metal-Enclosed Circuit Breaker Switchgear

Product Name: Low Voltage Metal-Enclosed Drawout Switchgear Type AKD-20 AR

PART1GENERAL

1.01SCOPE

  1. Provide a low voltage, rear-accessible, ANSI rated metal enclosed switchgear line-up with drawout ANSI rated power circuit breakers in an integrated system as detailed in this specification.
  2. This specification and associated drawings describe AKD-20ARLow Voltage Draw-out Switchgear assemblies constructed to ANSI C37.20.1 and ANSI C37.20.7 standards.
  3. The circuit breakers used in the arc resistant switchgear assemblies shall be drawout type EntelliGuard® G with EntelliGuard® TU electronic trip units as specified on the associated drawings. Circuit breakers shall have interrupting, close and latch, and 30-cycle withstand ratings that meet the application requirements. Square ratings (defined as interruption and 30-cycle withstand ratings are all equal) shall be available up to 100kA RMS without the use of fuses. The circuit breakers shall be available in 800, 1200, 1600, 2000, 3200, 4000A frame sizes. The circuit breakers shall have minimum Close and Latch rating of 42kA on all frame sizes. Thirty-cycle withstand rating shall be available up to 100 kA to provide maximum coordination with downstream circuit breakers. Universal rating plugs (range of 0.375 to 1 times the sensor value) shall determine the ampere rating of the circuit breaker. Optional key interlocks of Kirk Key type [shall, shall not] be provided. Optional front accessible metering and relaying CTs [shall, shall not] be provided. [Modbus, Profibus, no] communication protocol shall be provided.

1.02REFERENCES

  1. The AKD-20AR equipment lineup and power circuit breakers in this specification shall be designed, tested and manufactured according to latest revision of the following standards, unless otherwise noted.
  1. ANSI C37.16, Low Voltage Power Circuit Breakers and AC Power Circuit Protectors, Preferred Ratings, Related Requirements and Application Recommendations for
  1. ANSI C37.17, Trip Devices for AC and General Purpose DC Low-Voltage Power Circuit Breakers
  1. ANSI C37.50, Switchgear - Low Voltage AC Power Circuit Breakers Used in Enclosures - Test Procedures
  1. ANSI C37.51, Switchgear - Metal-Enclosed Low-Voltage AC Power Circuit Breaker Switchgear Assemblies - Conformance Test Procedures
  1. ANSI/IEEE C37.13, Low - Voltage AC Power Circuit Breakers Used In Enclosures
  1. ANSI/IEEE C37.20.1, Metal-Enclosed Low Voltage Power Circuit Breaker Switchgear
  1. ANSI/IEEE C37.20.7, Guide for Testing Metal-Enclosed Switchgear for Internal Arcing Faults
  1. ANSI/IEEE C57.13, Instrument Transformers, Requirements for
  1. ANSI/NFPA 70, National Electrical Code
  1. UL 1066, Low Voltage AC and DC Power Circuit Breakers Used in Enclosures
  1. UL 1558, Metal-Enclosed Low-Voltage Power Circuit Breaker Switchgear

1.03SUBMITTALS

  1. The contractor/installer shall provide the following documents as APPROVAL drawings to the engineer/owner for review and evaluation. The equipment manufacturer shall provide the factory shop drawings as detailed below. Manufacturing of the equipment will not begin until the submitted documents are acknowledged “APPROVED” or “APPROVED AS NOTED” by the engineer/owner and officially released for manufacture by the contractor/installer/distributor/owner.
  1. Shop drawings of the designed equipment including:
  2. Breaker Options Summary Sheets
  3. Detailed Bill of Material for Installed Component Devices
  4. Nameplate Engraving Sheets
  5. Equipment ratings (short circuit, voltage, continuous current)
  6. [Key Interlock ordering Sheets – If required]
  7. Summary of Equipment Options Sheets
  8. [Special Requirements Sheets – If required]
  9. Equipment One Line Bussing Diagram
  10. Front View (Elevation View)
  11. Electrical Schematic drawings
  12. Plan View showing Power Cable Conduit Areas and Control/Signal Conduit Areas
  13. Typical Section Side View showing breaker compartment and bus/cable compartment details
  14. Panel Layouts for each section and cubicle showing component device location
  15. Drawing Legend Sheet
  16. 3 Line Power Elementary Diagrams
  17. Control Circuit Wiring Diagrams
  18. [Control Power Throwover Diagram – If applicable]
  19. Device Communication Diagrams
  20. [Product data sheets – if required]
  21. [Heater Circuit and Auxiliary Circuit Diagrams – If applicable]
  1. Equipment product bulletin.
  1. The contractor/installer shall provide the following documents as RECORD drawings to the engineer/owner after the equipment has shipped. These drawings will reflect the “AS BUILT” condition of the specified equipment.
  1. Shop drawings of the manufactured equipment shall include all the same information as the APPROVAL drawings plus the following:
  1. Point-to-Point Wiring Diagrams for each section cubicle
  1. Equipment & breaker instruction books.
  1. Instruction books for major component devices installed by the manufacturing factory.
  1. Installation publications and drawings.

1.04RELAVENT SECTIONS (where applicable):

  1. Section 26 13 00 – Medium-Voltage Switchgear (Circuit Breaker and Load Interrupter)
  2. Section 33 77 26 – Medium-Voltage Utility Fusible Interrupter Switchgear
  3. Section 26 12 13 – Liquid-Filled Medium-Voltage Transformers
  4. Section 26 12 16 – Dry-Type, Medium-Voltage Transformers
  5. Section 26 12 19 – Pad-Mounted, Liquid-Filled, Medium-Voltage Transformers
  6. Section 26 11 00 – Substations (Primary and Secondary Unit)
  7. Section 26 43 13 – Transient-Voltage Suppression for Low-Voltage Electrical Power Circuits
  8. Section 28 27 13 – Electricity Metering for Low-Voltage Distribution Equipment
  9. Section 26 27 13.11 – Microprocessor-Based Metering Equipment
  10. Section 26 05 73 – Overcurrent Protective Device Coordination Study

1.05QUALITY ASSURANCE (QUALIFICATIONS)

  1. The manufacturer shall have specialized in the manufacture and assembly of low voltage switchgear for at least 20 years and shall have at least 5 years experience incorporating intelligent electronic devices (PLCs, Multifunction Meters, Communicating Trip Units, etc.) as functioning systems into the equipment lineup. If requested to do so, the manufacturer shall provide a listing of projects demonstrating their compliance to the engineer/owner.
  1. The equipment shall be manufactured in accordance with standards listed in the REFERENCES Section of this specification.

1.06DELIVERY, STORAGE, AND HANDLING

  1. Ambient temperature of the area where the equipment will be installed must be between minus 30 degree C (minus 22 degree F) and plus 40 degrees C (104 degree F) and shall be protected to prevent moisture from entering equipment.
  1. The equipment shall be shipped FOB jobsite. It is the responsibility of the contractor/installer to inspect and report any damage to a manufacturer’s representative who shall handle any freight damage claim.
  1. Within 24 hours of receiving the equipment, the contractor/installer shall heat the equipment enclosures with a temporary heat source to prevent condensation per the storage instructions of the equipment manufacturer.
  1. The contractor/installer shall handle the equipment in accordance with all appropriate NEMA, ANSI and manufacturer's written instructions to avoid damaging the equipment, installed devices and finish.
  1. The contractor/installer shall protect and handle the equipment in accordance with recommended practices listed in manufacturer's installation publications and/or maintenance manuals. When stored, the equipment shall be located in a clean, dry space and shall maintain factory protection or cover the equipment with heavy canvas to keep out dirt, water, construction debris, and traffic.
  1. The contractor/installer shall follow all appropriate standards and service conditions before, during and after the equipment installation.
  1. The final location of the equipment shall be in a well-ventilated area, free from excess humidity, dust and dirt and away from hazardous materials.

1.07WARRANTY

  1. The manufacturer warrants the low voltage metal-enclosed switchgear to be free from defects in materials and workmanship for 1 year from date of installation or 18 months from date of shipment, whichever occurs first. The equipment must be received, stored and installed in accordance with the manufacturer’s installation publications and/or maintenance manuals to avoid nullifying this warranty.
  1. In the event that any warranty work needs to be performed, a representative of the manufacturer shall be notified in writing of the problem. The manufacturer’s factory will then issue instructions and any materials to correct the problem. All warranty work must be performed by the manufacturer at the manufacturer’s discretion in order to maintain the manufacturer’s warranty.

1.08FIELD MEASUREMENTS

A.The contractor/installer shall make all necessary field measurements to verify that the low voltage switchgear lineup shall fit in allocated space in full compliance with minimum required clearances recommended by the manufacturer, specified in National Electrical Code and required by any applicable local/facility requirements.

PART2PRODUCTS

2.01DESIGN

  1. General Electric AKD-20ARlow voltage metal enclosed switchgear has been used as the basis for design for this project. Other manufacturers' products of equivalent quality, dimensions and operating features that could be considered “as equal” must comply with all requirements specified in these specifications and as indicated in the project contract drawings.
  1. Any and all exceptions to the requirements detailed below shall be included in the contractor’s proposal so that the engineer or owner’s representative can easily make a comparison to this base-line specification document. The contractor shall document in their proposal that the manufacturer provided detailed information to support exceptions or substituted products.
  1. If no exceptions or qualifications are contained in the alternate contractor’s and manufacturer’s proposal, the alternate manufacturer shall provide exactly what is detailed in both this specification and the project contract documents. Failure to meet this requirement will result in the rejection of the proposal based on non-compliance with the technical performance requirements of this specification.
  1. The first source of general information shall be these general specifications; however, detailed and specific information contained in the drawings will take precedence over these general specifications as the drawings contain project specific information. In the event of a conflict between the plans and specifications, the owner/engineer will determine which is correct.

2.02EQUIPMENT LINE-UP INFORMATION

  1. The General Electric AKD-20 AR low voltage metal enclosed switchgear is the basis for design. The switchgear system lineup shall be completely factory assembled and shall contain upper, lower and side metal compartmentalized units for removable power circuit breakers. The switchgear assemblies and circuit breakers shall be constructed by the same manufacturer.
  1. The General Electric EntelliGuard® G circuit breakers are used as the basis for design. The Low Voltage Power Circuit Breakers (air circuit breakers) shall be UL listed per UL 1066 and built to pertinent ANSI specifications. Use of, or substitution by UL 489 listed circuit breakers for any protective device is unacceptable and will be rejected by the owner/engineer.
  1. The manufacturer shall provide drawings in the following format. Refer to the SUBMITTALS section for the specific documentation requirements.
  1. Approval and Record documentation shall be supplied in an all [electronic][and][or][paper] format as detailed below:
  1. [Electronic equipment mechanical and electrical drawings shall be provided in AutoCAD dwg or dxf formats.]
  1. [Electronic general information details (nameplate schedules, material lists, etc.) shall be provided in either Microsoft Word doc format or Rich Text (rtf) format.]
  1. [Other information (data sheets, standard typical diagrams, etc.) shall be provided in Acrobat pdf format.]
  1. [Paper documentation shall be provided on size “A” (8.5” x 11”) or size “B” (11” x 17”) paper to facilitate easy copying.]
  1. Submittal and record documents shall include a list of potential spare parts to include all trip devices, protective relays, meters, instrument transformers for meters and relays, communicating devices and control devices.
  1. [Insert quantity of paper copies] copies shall be provided.
  1. The following factory accommodations are required for this project:
  1. Factory certified test reports [are not required as normal factory testing procedures are acceptable.][shall be issued at the conclusion of the factory testing. The format of the information shall be the same as described in the “Approval and Record documentation” section above.]
  1. Factory witness testing [is not required as normal factory testing procedures are acceptable.][shall be provided. The manufacturer shall notify the owner/engineer at least 2 weeks in advance of the test date. The test shall demonstrate the successful operation of the equipment as it will be operated in the owner’s facility.]
  1. Customer inspection [is not required as normal factory testing procedures are acceptable.][shall be provided so that the owner/engineer/owner’s representative can visit the factory and view the assembled equipment prior to shipment to visually confirm the correctness of the final product prior to shipment. The manufacturer shall notify the owner/engineer at least 2 weeks in advance of the final assembly date]

E.The manufacturer shall be ISO 9001 or 9002 certified.

2.03EQUIPMENT SUMMARY INFORMATION

  1. The low voltage metal enclosed switchgear lineup shall be engineered and fabricated to meet the specific project electrical distribution, protection and control requirements as detailed in this specification. The specific equipment lineup properties are listed below.
  1. Equipment construction shall house all live components in a grounded metal enclosure 92 inches high with a code gauge modular designed steel frame with removable plates. The overall lineup enclosure construction type shall be as Indoor type NEMA 1. The enclosure is intended for indoor use primarily to provide a degree of protection against contact with the enclosed equipment.
  1. To facilitate the ease of equipment assembly and installation, the MAXIMUM equipment shipping split section width shall be [120 inches to minimize the amount of assembly sections.][38 inches to provide individual vertical stacks, which will allow easier egress to the final location.][Insert width of shipping section in inches.] (note to Specification writer: Please check with your Ge representative to confirm that the required sizes can be provided)
  1. When shipped from the factory the packaging shall be [standard domestic factory packaging (poly wrapped, cardboard/Styrofoam cushions, etc.), special export packaging is not required.][suitable for special conditions, special export packaging is required.]
  1. The switchgear lineup shall be rated and labeled to receive a power supply nominal Line-to-Line voltage rating [of 208 Volts AC][of 240Volts AC][of 480 Volts AC][of 600 Volts AC] . System control power shall be derived from the line side of all sources feeding the switchgear.
  1. The switchgear lineup shall be rated and labeled to receive a phasing and wire arrangement [of 3-Phase / 3-Wire][of 3-Phase / 4-Wire][as shown on the project drawings].
  1. The switchgear lineup shall be rated and labeled to receive a frequency rating [of 60 Hertz][of 50 Hertz][as shown on the project drawings].
  1. All bus bars in the switchgear lineup shall be braced and labeled to withstand the short circuit mechanical forces [of 65,000 Amperes @ rated voltage][100,000 Amperes @ rated voltage] [as shown on the project drawings].
  1. The main bus in the switchgear lineup shall be made of copper and shall be rated and labeled to handle an electrical load of[1600 Amperes][2000 Amperes][3200 Amperes][4000 Amperes][as shown on the project drawings].
  1. The overall short circuit value of the switchgear lineup shall be rated and labeled as [30,000 Amperes @ rated voltage][42,000 Amperes @ rated voltage][50,000 Amperes @ rated voltage][65,000 Amperes @ rated voltage][shown on the project drawings].
  1. A ground bus shall be secured to each vertical section structure. It shall also extend the entire length of switchgear lineup and shall be equipped with a 4/0 terminal for connection to the building’s ground system. The ground bus in the switchgear lineup shall be made of copper and shall be [suitable for the short circuit rating of the switchgear][as shown on the project drawings].
  1. If provided, the copper neutral bus shall be mounted on stand off insulators to isolate it from ground. The specifics of the equipment neutral bus [do not apply as the equipment power source contains no neutral connection and therefore no neutral bus is required in the equipment lineup][shall have a full rating (100%) neutral bar, the neutral bus and the phase buses shall be identical in ratings and size][shall have a half rated (50%) neutral bar, the neutral bus shall be half the rating and size of the phase buses][shall be as shown on the project drawings].
  1. To facilitate the ease of dressing the incoming and feeder cables [only the ground bus shall be considered as the lineup has no neutral bus][the neutral bus shall be located in an upper location as the majority of cables will exit out the bottom of the equipment][the neutral bus shall be located in a lower location as the majority of cables will exit out the top of the][shall be as shown on the project drawings].
  1. The configuration of the system neutral for high resistance grounded systems: [Grounding shall be as indicated on the contract drawings. A CT shall be provided to measure neutral resistor current. Resistor shall be adjustable to allow a setting above the system charging current].
  1. Grounding for solidly grounded WYE systems:. The system shall be grounded and bonded as per contract drawings. Where equipment needs to be considered as “Service Entrance Equipment” all applicable requirements of the National Electrical Code as interpreted by the local jurisdiction shall be followed.
  1. The same material shall be used at the vertical-to-horizontal bus connections and at points where vertical bus connects to bus bars supplying power to circuit breaker compartments. All bus material and plating in the switchgear lineup shall be [copper buses with silver plating][copper buses with tin plating].
  1. All bus hardware shall be high tensile strength zinc chromate plated steel. Split washers or similar shall be provided at all bus joints.
  1. The vertical bus shall be held rigid in support structure of short circuit resistant, molded glass reinforced polyester bases to inhibit the spread of arcing faults. All bus bars shall be arranged to permit the addition of future additions.
  1. The switchgear shall have rear cable terminal compartments. The cable bending space shall meet National Electrical Code requirements.
  1. The overall equipment lineup depth [shall be 54 inches deep}[shall be 60 inches deep][shall be 67 inches deep][74 inches deep][shall be as shown on the project drawings]. In all cases sufficient space shall be provided to accommodate conduit openings and cable entrances as indicated on the contract drawings or conductor schedules.
  1. To accommodate cables and conduits [no extension is required] [extended depth shall be provided].
  1. All sheet metal parts that are not plated shall be painted using a multi-step cleaning and painting process. Sheet metal parts shall be prepared for painting through a 10-stage cleaning process. The cleaning process shall include two hot alkaline washes, a triple rinse, heated iron phosphate coating, rinse, non-chrome sealer, rinse, and a final de-ionized water rinse. The cleaned parts shall immediately pass through a drying oven and then move into the powder coat area. Sheet metal part profiles shall be sensed at the start of the powder coat area and automatically adjust the positions of the spray guns to insure complete coverage of all metal surfaces with ANSI 61 light gray polyester powder. Painted parts shall then travel through a curing oven followed by a cooling process prior to removal from the continuous conveyor system. Finished parts shall have an average paint thickness of 2-3 mils and shall withstand 600 hours of salt spray (per ASTM B 117 and ASTM D 1654) as well as 1000 hours of 100% humidity at 45 degrees Centigrade. Finished parts shall also meet the requirements of ASTM D 3359 for adhesion and ASTM B 117 / ASTM D 1654 for UV-A gloss retention.

2.04EQUIPMENT OPTIONS – ELECTRICAL