Attachment 3 - 262300 LOW-VOLTAGE SWITCHGEAR JAN17RR.pdf

JUBA ELECTRICAL UPGRADE DEVELOPMENT July 13, 2020

JUBA SOUTH SUDAN Issued for Bid

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 1

SECTION 262300 - LOW-VOLTAGE SWITCHGEAR

PART 1 - GENERAL

1.1 SUMMARY

A. This Section includes metal-enclosed, low-voltage, power circuit-breaker switchgear rated

1000 V and less for use in AC systems.

B. Related Sections include the following:

1. Section 260505 “Common Work Results for Electrical, Communication and Electronic

Safety” for facility voltages and safety accessories.

2. [Division 26 Section on vibration and seismic controls for electrical systems for mounting and anchoring switchgear.]

3. Section 260573 “Overcurrent Protective Device Coordination Study” for arc flash study, ARMS reduction level or alternative means of compliance for worker safety, and arc flash training.

4. Section 260915 "Electrical Power Monitoring and Controls" for interfacing communication and metering requirements.

5. Section 262313 "Paralleling Switchgear".

6. Section 262315 "Double-Ended Switchgear".

7. Division 26 Section on fuses for fuses and spare-fuse cabinets.

1.2 SUBMITTALS

A. Product Data: For each type of switchgear, circuit breaker, accessory, and component indicated.

Include dimensions and manufacturers' technical data on features, performance, electrical characteristics, ratings, and finishes.

B. Shop Drawings: For each type of switchgear and related equipment.

1. Dimensioned plans, elevations, sections, and details, including required clearances and service space around equipment. Include the following:

a. Tabulation of installed devices with features and ratings.

b. Enclosure types and details.

c. Outline and general arrangement drawing showing dimensions, shipping sections, and weights of each assembled section.

d. Bus configuration with size and number of conductors in each bus run, including phase, neutral, and ground conductors of main and branch buses.

e. Current rating of buses.

f. Short-time and short-circuit current rating of switchgear assembly.

g. Nameplate legends.

h. Mimic-bus diagram.

i. Utility company's metering provisions with indication of approval by utility company.

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j. Arc flash reduction switch.

k. Features, characteristics, ratings, and factory settings of individual overcurrent protective devices and auxiliary components.

2. Wiring Diagrams: Power, signal, and control wiring.

C. Coordination Drawings: Floor plans showing dimensioned layout, required working clearances, and required area above and around switchgear where pipe and ducts are prohibited. Show switchgear layout and relationships between components and adjacent structural and mechanical elements. Show support locations, type of support, and weight on each support. Indicate field measurements.

D. Samples: Representative portion of mimic bus with specified finish. Manufacturer's color charts showing colors available for mimic bus.

E. Field quality-control test reports.

F. Certificates of Compliance: Manufacturer of switchgear shall certify compliance with referenced standards

G. Qualification data for firms and persons as required in Article on QUALITY ASSURANCE.

1. Testing Agency:

2. Support Services Vendor: Identify vendor firm name and contact, location, distance from project, number of years servicing product line.

H. Updated mimic-bus diagram reflecting field changes after final switchgear load connections have been made, for record.

I. Operation and Maintenance Data: For switchgear and components to include in emergency, operation, and maintenance manuals. In addition to items specified in Division 01 Section

"Operation and Maintenance Data," include the following:

1. Manufacturer's written instructions for testing and adjusting overcurrent protective devices.

2. Time-current curves, including selectable ranges for each type of overcurrent protective device.

1.3 OWNERSHIP OF PROPRIETARY MATERIAL

A. Government shall retain all rights to software and passwords used for this project.

B. Government will sign copy of the manufacturer’s standard software and firmware licensing agreement as condition of this contract. Such license shall grant use of all programs and application software to Government as defined by manufacturer’s license agreement, while protecting manufacturer’s rights to disclosure of Trade Secrets contained within such software.

C. Licensing agreement shall not preclude use of software by individuals under contract to

Government for commissioning, servicing, or altering system in future. Use of software by individuals under contract to Government will be restricted to use on Government’s computers, and only for purpose of commissioning, servicing, or altering installed system.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 3

D. All project developed software, files and documentation shall become property of Government.

1.4 QUALITY ASSURANCE

A. Independent Testing Agency Qualifications: Testing agency that is member company of

InterNational Electrical Testing Association (NETA), and that is acceptable to Contracting

Officer/COR based upon input from OBO/PDCS/DE/EE.

1. Testing Agency's Field Supervisor: Person currently certified by NETA or National

Institute for Certification in Engineering Technologies (NICET) to supervise on-site testing specified in this Section.

B. Source Limitations: Obtain switchgear through one source from single manufacturer.

C. [Basis of Design: Drawings indicate size, profiles, and dimensional requirements of switchgear and are based on the specific system indicated. Other manufacturers' products complying with requirements may be considered.].

D. Comply with the OBO Electrical Code (NFPA 70 “National Electrical Code as amended by

OBO).

1. Electrical Components, Devices, and Accessories: Listed and labeled in accordance with

Chapter 1 of the OBO Electrical Code by testing agency acceptable to Contracting

Officer/COR based upon input from OBO/PDCS/DE/EE, and marked for intended use.

E. Standards: In addition to standards identified elsewhere in this Section, conform to the following:

1. Institute of Electrical and Electronics Engineers (ANSI/IEEE):

a. C37.16 “Switchgear - Low-Voltage Power Circuit Breakers and AC Power Circuit

Protectors - Preferred Ratings, Related Requirements, and Application

Recommendations”

b. C37.50 “Test Procedures of Low-Voltage AC Power Circuit Breakers Used in

Enclosures”

c. C37.51 “Conformance Test Procedures of Metal-Enclosed Low-Voltage AC

Power Circuit Breaker Switchgear Assemblies”

2. Underwriters Laboratories, Inc. (UL):

a. 1558 “Metal Enclosed Low-Voltage Power Circuit Breaker Switchgear”

F. Support Service Capability: Manufacturer approved support services Vendor to commission switchgear and available to provide ongoing maintenance services shall be approved by manufacturer. Vendor shall be located within 1500 km (1000 miles) of project site. Vendor shall have performed these services on this product line for at least five years.

1.5 DELIVERY, STORAGE, AND HANDLING

A. Deliver switchgear in sections of lengths that can be moved past obstructions in delivery path.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 4

B. Storage: Store in one of the following manners:

1. Store switchgear indoors in clean dry space with uniform temperature to prevent condensation. Protect switchgear from exposure to dirt, fumes, water, corrosive substances, and physical damage.

2. If stored in areas subjected to weather, cover switchgear to provide protection from weather, dirt, dust, corrosive substances, and physical damage. Remove loose packing and flammable materials from inside switchgear; install electric heating (250 W per section) to prevent condensation.

1.6 PROJECT CONDITIONS

A. [Installation Pathway: For renovation and system upgrade projects, remove and replace building components and structures to provide pathway for moving switchgear into place.]

B. [Existing Utilities: Do not interrupt utilities serving facilities occupied by Government or others unless permitted under the following conditions and then only after arranging to provide temporary utility services according to requirements indicated:

1. Notify Contracting Officer/COR not less than seven days in advance of proposed utility interruptions. Identify extent and duration of utility interruptions.

2. Indicate method of providing temporary utilities.

3. Do not proceed with utility interruptions without Contracting Officer/COR’s written permission.]

C. Product Selection for Restricted Space: Drawings indicate maximum dimensions for switchgear, including clearances between switchgear, and adjacent surfaces and other items. Comply with indicated maximum dimensions.

D. Environmental Limitations: Rate equipment for continuous operation under the following conditions, unless otherwise indicated:

1. Ambient Temperature: Not exceeding [40][50][60] deg C.

2. Altitude: Derate as required if over <insert altitude> above sea level.

1.7 COORDINATION

A. Coordinate layout and installation of switchgear and components with other construction that penetrates ceilings or is supported by them, including conduit, piping, equipment, and adjacent surfaces. Maintain required clearances for workspace and equipment access doors and panels.

B. Coordinate size and location of concrete bases.

1.8 EXTRA MATERIALS

A. Furnish extra materials described below that match products installed and that are packaged with protective covering for storage and identified with labels describing contents.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 5

1. Fuses: Six of each type and rating used. Include spares for potential transformer fuses, control power fuses, and fuses and fusible devices for fused circuit breakers.

2. Indicating Lights: Six of each type installed.

3. Touchup Paint: Three containers of paint matching enclosure finish, each 250 mL.

PART 2 - PRODUCTS

2.1 RATINGS

A. Nominal System Voltage: Site Distribution Voltage.

B. Main-Bus Continuous: 4000 A.

C. Short-Time and Short-Circuit Current: Match rating of highest-rated circuit breaker in switchgear assembly.

2.2 SWITCHGEAR FEEDERS

A. Circuit breakers shall be a minimum of 800-ampere frame.

B. Breakers/feeders with trip ratings at or under 800 ampere shall be switchboard construction. See

Division 26 Section on switchboards.

2.3 FABRICATION

A. Factory assembled and tested and complying with IEEE C37.20.1 “Metal Enclosed Low-Voltage

Power Circuit-Breaker Switchgear.”

B. Indoor Enclosure Material: Steel.

C. Finish: Manufacturer's standard gray finish over rust-inhibiting primer on phosphatizing-treated metal surfaces, complying with IEEE C37.20.1.

D. Extend section barriers between main and tie circuit-breaker compartments to rear of section.

E. Arrange bus isolation barriers to isolate line bus from load bus at each main and tie circuit breaker.

F. Equip circuit-breaker compartments to house drawout-type circuit breakers, and fit with hinged outer doors.

G. Fabricate enclosure with removable, hinged, rear cover panels, secured by captive thumbscrews, to allow access to rear interior of switchgear.

H. Auxiliary Compartments: Match and align with basic switchgear assembly. Include the following:

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 6

1. Utility metering compartment that complies with utility company requirements.

2. Bus transition sections.

3. [Incoming-line pull sections.]

4. Hinged front panels for access to metering, accessory, and blank compartments.

5. Pull box on top of switchgear for extra room for pulling cable, with removable top, front, and side covers and ventilation provisions adequate to maintain air temperature in pull box within same limits as switchgear.

a. Set pull box back from front to clear circuit-breaker lifting mechanism.

b. Bottom: Insulating, fire-resistant material with separate holes for cable drops into switchgear.

c. Cable Supports: Arranged to ease cabling and adequate to support cables indicated, including those for future installation.

I. Provide bus bars between vertical sections and between compartments. Cable connections are not permitted.

1. Main Phase Bus: Fully rated the entire length of assembly; do not taper.

2. Neutral Bus: 100 percent of phase-bus ampacity. Equip bus with pressure-connector terminations for outgoing circuit neutral conductors..

3. Vertical Section Bus Size: Comply with IEEE C37.20.1, including allowance for spare circuit breakers and spaces for future circuit breakers.

4. Phase- and Neutral-Bus Material: Hard-drawn copper of 98 percent minimum conductivity, with copper feeder circuit-breaker line connections.

5. Use copper for connecting circuit-breaker line to copper bus.

6. Contact Surfaces of Buses: Silver plated.

7. Feeder Circuit-Breaker Load Terminals: Silver-plated copper bus extensions equipped with pressure connectors for outgoing circuit conductors.

8. Ground Bus: Hard-drawn copper of 98 percent minimum conductivity, with pressure connector for feeder and branch-circuit ground conductors, minimum size 6 mm by 50 mm.

Extend entire length of the switchgear.

9. Supports and Bracing for Buses: Adequate strength for indicated short-circuit currents.

10. Neutral bus equipped with pressure-connector terminations for outgoing circuit neutral conductors.

11. Neutral Disconnect Link: Bolted, uninsulated, 6 mm by 50 mm copper bus, arranged to connect neutral bus to ground bus, if required.

12. Facilitate future extensions from either end of main phase, neutral, and ground bus by providing predrilled bolt-holes and connecting links.

13. Bus-Bar Insulation: Individual bus bars wrapped with factory-applied, flame-retardant tape, or vertical and horizontal busses shall be isolated from the cable compartments by glass reinforced polyester barriers.

14. Size busbars to limit temperature rise to 65 deg C above 40 deg C ambient temperature, but shall not exceed 155 amperes per square centimeter.

15. Brace busbars contained in each section to withstand mechanical forces exerted during short circuit conditions. Minimum short circuit bracing shall be 65,000 amperes RMS symmetrical at rated voltage.

16. Completely isolate/insulate entire switchgear bus system with insulated nut covers or grounded metal barriers to preclude accidental contact with live busbars while working in outgoing power cable compartment. The only exposed energized parts in rear power cable compartment shall be outgoing feeder connections.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 7

17. A-B-C type bus arrangement, left-to-right, top-to-bottom, and front-to-rear, as viewed from the front, shall be used throughout. Mount main horizontal bus bars with all three phases arranged in same vertical plane. Provide full capacity neutral.

18. Identify busbars in each cubicle, both line and load, with adhesive red letters applied to busbar. This identification shall be in each cubicle, as seen from rear cable compartment for all phases, neutral and ground busses in accordance with A-B-C type bus arrangement defined above.

19. Busbar supports shall be non-carbonizing, non-tracking insulators arranged to provide short circuit bracing of 65,000 amperes symmetrical at rated voltage, three-phase.

20. Provide fire-resistive supports to which cable shall be adequately secured and racked within rear compartment.

21. Segregate buses in separate compartment from breaker and feeder cable compartment.

22. Provide main breaker section with vertical barriers between sections extending all the way to rear.

23. Provide main circuit breaker with horizontal isolation barrier or combination of barriers to completely separate bus line from load bus.

24. Provide black vinyl plastic "mimic bus" on front of switchgear depicting current distribution (flow) through each circuit protective device. Secure bus to switchgear enclosure using screws and nuts.

25. From terminals on load side of breaker compartment, extend insulated bus toward back of board to vertical wiring compartment to avoid cables threaded through line bus bars.

J. Fabricate switchgear with ability to remove access covers to facilitate maintenance activities.

Facilitate access to inspect device while circuits are energized (e.g., using infrared imaging).

Minimum distances to energized circuits shall comply with OSHA standard in CFR 29, Part

1910.333.

2.4 COMPONENTS

A. Instrument Transformers: Comply with IEEE C57.13.

1. Potential Transformers: Secondary-voltage rating of 120 V and NEMA accuracy class of

0.3 with burdens of W, X, and Y.

2. Current Transformers: Ratios as indicated; burden and accuracy class suitable for connected relays, meters, and instruments.

B. [Multifunction Digital-Metering Monitor: UL-listed or -recognized, microprocessor-based unit suitable for three- or four-wire systems and with the following features:

1. Inputs from sensors or 5-A current-transformer secondaries, and potential terminals rated to 600 V.

2. Switch-selectable digital display of the following:

a. Phase Currents, Each Phase: Plus-or-minus 1 percent.

b. Phase-to-Phase Voltages, Three-Phase: Plus-or-minus 1 percent.

c. Phase-to-Neutral Voltages, Three-Phase: Plus-or-minus 1 percent.

d. Three-Phase Real Power: Plus-or-minus 2 percent.

e. Three-Phase Reactive Power: Plus-or-minus 2 percent.

f. Power Factor: Plus-or-minus 2 percent.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 8

g. Frequency: Plus-or-minus 0.5 percent.

h. Integrated Demand, with Demand Interval Selectable from 5 to 60 Minutes:

Plus-or-minus 2 percent.

i. Accumulated energy, in megawatt hours (joules), plus-or-minus 2 percent;

stored values unaffected by power outages for up to 72 hours.

3. Mounting: Display and control unit flush or semiflush mounted in instrument compartment door.]

C. [Analog Instruments: Rectangular, 115-mm square, accurate within 1 percent, semiflush, with antiparallax 250-degree scale and external zero adjustment, complying with

ANSI C39.1.

1. Voltmeters: Cover an expanded scale range of normal voltage plus 10 percent.

2. Voltmeter Selector Switch: Rotary type with off position to provide readings of phase-to-phase and phase-to-neutral voltages.

3. Ammeters: Cover an expanded scale range of bus rating plus 10 percent.

4. Ammeter Selector Switch: Permits current reading in each phase and keeps current-transformer secondary circuits closed in off position.

5. Locate meter and selector switch on circuit-breaker compartment door for indicated feeder circuits only.

6. Watt-Hour Meters: Flush or semiflush type, 5 A, 240 V, three-phase, 3 wire; with three elements, 15-minute indicating demand register, and provision for testing and adding pulse initiation.

7. Recording Demand Meter: Usable as totalizing relay or indicating and recording maximum demand meter with 15-minute interval.

a. Operation: Meter counts and records a succession of pulses entering two channels.

b. Housing: Drawout, back-connected case arranged for semiflush mounting.]

D. [Relays: Comply with IEEE C37.90, types and settings as indicated; with test blocks and plugs.]

E. Surge Arresters: Distribution class, metal-oxide-varistor type. Comply with IEEE C62.11 and

NEMA LA 1.

1. Install in cable termination compartments and connect in each phase of circuit.

2. Coordinate rating with circuit voltage.

3. Status and indicator lights shall be visible to operators in room with switchgear.

F. Provision for Future Devices: Equip compartments with rails, mounting brackets, supports, necessary appurtenances, and bus connections.

G. Provide 10 percent spare circuit breakers installed in the switchgear, 20 percent spaces for future breakers, and 20 percent overall spare current carrying capacity for future expansion.

H. [Fungus Proofing: Permanent fungicidal treatment for switchgear interior, including instruments and instrument transformers.]

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 9

I. Control Power Supply: Control power transformer supplying 220 or 240 V control circuits through secondary disconnect devices. Include the following features:

1. Dry-type transformers, in separate compartments for units larger than 3 kVA, including primary and secondary fuses.

2. Two control power transformers in separate compartments with necessary interlocking relays; each transformer connected to line side of associated main circuit breaker.

a. Secondary windings connected through relay or relays to control bus to effect automatic transfer scheme.

b. Secondary windings connected through internal automatic transfer switch to switchgear control power bus.

3. Control Power Fuses: Primary and secondary fuses with current-limiting and overload protection.

J. Control Wiring: Factory installed, complete with bundling, lacing, and protection; and complying with the following:

1. Flexible conductors for 10 mm2 and smaller, for conductors across hinges and for conductors for interconnections between shipping units.

2. Conductors sized according to the NFPA 70 for the duty required.

K. Operating Frequency: American manufactured switchgear is normally designed to operate at 60

Hertz. Where operation at other frequencies is required, consult manufacturer for derating factor.

Most manufacturers do not derate for operation at 50 Hertz.

L. Furnish and install a power system controller for controlling the Essential Bus main breaker, Utility Bus main breaker, HVAC bus main breaker, and tie breaker between Essential and Utility busses.

1. The controller shall utilize a programmable logic controller (PLC). Electromagnetic control relays are not acceptable.

2. Provide duplicate “hot standby” PLC in same enclosure as primary. Changeover shall require no more than moving keyed wiring connects and resetting processor but automatic switchover without manual intervention is preferred.

3. Provide 24 hour dedicated battery for system back up.

M. Arc Reduction Maintenance Switch (ARMS): Dual parameter sets that enable trip unit, when activated by maintenance personnel, to automatically lower instantaneous setting, and thereby lower available energy in fault condition (commonly referred to as “maintenance mode”); this causes breaker to trip faster when maintenance is being performed in proximity to energized equipment, thus minimizing arc flash dangers. Refer to Section 260573 “Overcurrent Protective

Device Coordination Study” for required arc flash levels or alternative means of compliance for worker safety protection.

2.5 CIRCUIT BREAKERS

A. Construction and Circuit Breakers, General:

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 10

1. Switchgear For Operation Above 600 Volts: Provide metal-clad construction. Provide draw-out, vacuum break circuit breakers selected for appropriate voltage, frequency, impulse withstand voltage, and interrupting duty. Use direct current control. Provide copper busbars.

2. Switchgear For Operation At 600 Volts Or Below: Provide metal-clad construction consisting of metal-enclosed type construction or molded case circuit breakers. Provide draw-out, air break metal enclosed circuit breakers selected for appropriate voltage, frequency, impulse withstand voltage, and interrupting duty. Alternating current control and solid-state trip units are preferred. Adjustable long-time, short-time, instantaneous, and ground fault sensing shall be selected to coordinate with other system protective devices. Provide copper busbars.

B. Description: Comply with IEEE C37.13 “Standard for Low-Voltage AC Power Circuit Breakers

Used in Enclosures.”

C. Ratings: As indicated for continuous, interrupting, and short-time current ratings for each circuit breaker; voltage and frequency ratings same as switchgear.

D. Operating Mechanism: Mechanically and electrically trip-free, stored-energy operating mechanism with the following features:

1. Normal Closing Speed: Independent of both control and operator.

2. Stored-Energy Mechanism: Electrically charged.

3. Operation counter.

E. Trip Devices: Solid-state, overcurrent trip-device system consisting of one or two current transformers or sensors per phase, release mechanism, and the following features:.

1. Functions: Long-time-delay, short-time-delay, and instantaneous-trip functions, independent of each other in both action and adjustment.

2. Temperature Compensation: Ensures accuracy and calibration stability from minus 5 to plus 40 deg C.

3. Field-adjustable, time-current characteristics.

4. Current Adjustability: Dial settings and rating plugs on trip units or sensors on circuit breakers, or a combination of these methods.

5. Three bands, minimum, for long-time- and short-time-delay functions; marked

"minimum," "intermediate," and "maximum."

6. Pickup Points: Five minimum, for long-time- and short-time-trip functions. Equip short-time-trip function for switchable I2t operation.

7. Pickup Points: Five minimum, for instantaneous-trip functions.

8. Ground-fault protection with at least three short-time-delay settings and three trip-time-delay bands; adjustable current pickup. Arrange to provide protection for the following:

a. Three-wire circuit or system.

b. Four-wire circuit or system.

c. Four-wire, double-ended substation.

9. Trip Indication: Labeled, battery-powered lights or mechanical targets on trip device to indicate type of fault.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 11

F. Auxiliary Contacts: For interlocking or remote indication of circuit-breaker position, with spare auxiliary switches and other auxiliary switches required for normal circuit-breaker operation, quantity as indicated. Each consists of two Type "a" and two Type "b" stages (contacts) wired through secondary disconnect devices to terminal block in stationary housing.

G. Drawout Features: Circuit-breaker mounting assembly equipped with a racking mechanism to position circuit breaker and hold it rigidly in connected, test, and disconnected positions. Include the following features:

1. Interlocks: Prevent movement of circuit breaker to or from connected position when it is closed, and prevent closure of circuit breaker unless it is in connected, test, or disconnected position.

2. Circuit-Breaker Positioning: Open circuit breaker may be racked to or from connected, test, and disconnected positions only with associated compartment door closed, unless live parts are covered by full dead-front shield. Open circuit breaker may be manually withdrawn to position for removal from structure with door open. Status for connection devices for different positions includes the following:

a. Test Position: Primary disconnect devices disengaged, and secondary disconnect devices and ground contact engaged.

b. Disconnected Position: Primary and secondary devices and ground contact disengaged.

3. Operator shall be able to close and trip circuit breakers electrically as "test" made by using control switches on front. Electrical interlocks shall still work to prevent inadvertent paralleling.

H. Arc Chutes: Readily removable from associated circuit breaker when it is in disconnected position, and arranged to permit inspection of contacts without removing circuit breaker from switchgear.

I. Padlocking Provisions: For installing at least three padlocks on each circuit breaker to secure its enclosure and prevent movement of drawout mechanism.

J. Operating Handle: One for each circuit breaker capable of manual operation.

K. Electric Close Button: One for each electrically operated circuit breaker.

L. Mechanical Interlocking of Circuit Breakers: Uses mechanical tripping lever or equivalent design and electrical interlocks.

M. Key Interlocks: Arranged so keys are attached at devices indicated. Mountings and hardware are included where future installation of key-interlock devices is indicated.

N. Undervoltage Trip Devices:

1. Instantaneous, with adjustable pickup voltage.

2. Adjustable time-delay and pickup voltage.

O. Shunt-Trip Devices: Where indicated.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 12

P. Fused Circuit Breakers: Circuit breaker and fuse combinations complying with requirements for circuit breakers and trip devices and with the following:

1. Fuses: NEMA FU 1, Class L current limiting, sized to coordinate with and protect associated circuit breaker.

2. Circuit Breakers with Frame Size 1600 A and Smaller: Fuses on line side of associated circuit breaker, on common drawout mounting, arranged so fuses are accessible only when circuit breaker is in disconnected position.

3. Circuit Breakers with Frame Sizes More Than 1600 A: Fuses and circuit breakers may be installed in separate compartments on separate drawout mountings. Fuse drawout element is interlocked with associated power circuit breaker to prevent drawing out fuse element unless circuit breaker is in open position.

4. Open-Fuse Trip Device: Positive means of tripping and holding circuit breaker in open position when fuse opens. Open-fuse status is indicated at front of circuit breaker or fuse drawout element.

Q. Indicating Lights: To indicate circuit breaker is open or closed, for main and bus tie circuit breakers interlocked either with each other or with external devices.

2.6 ACCESSORIES

A. Accessory Set: Furnish tools and miscellaneous items required for circuit-breaker and switchgear test, inspection, maintenance, and operation.

1. Racking handle to manually move circuit breaker between connected and disconnected positions.

2. Portable test set for testing all functions of circuit-breaker, solid-state trip devices without removal from switchgear.

3. Relay and meter test plugs suitable for testing switchgear meters and switchgear class relays.

B. [Circuit-Breaker Removal Apparatus: Portable, floor-supported, roller-base, elevating carriage arranged for moving circuit breakers in and out of compartments.]

C. [Circuit-Breaker Removal Apparatus: Overhead-circuit-breaker lifting device, track mounted at top front of switchgear and complete with hoist and lifting yokes matching each size of drawout circuit breaker installed.]

D. Control Cabinets:

1. Provide true redundant controllers for operation to include cabinets, controllers, and independent wiring with manual toggle selector switch between the two controllers.

2. Mount switchgear control components in individual cabinets; cabinet footprint shall be approximately 600 mm (2 feet) deep x 1500 mm (5 feet) high.

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3. Cabinet shall consist of two-step rack with electrical connections between battery cells and between rows of cells. Include two flexible connectors with bolted-type terminals for output leads. Battery rack, cell supports, and anchorage shall be rated for seismic requirements of location.

4. Access to cabinet shall be from front, using hinged doors.

E. Spare-Fuse Cabinet: Identified and compartmented steel box, or cabinet with lockable door.

F. Storage for Manual: Include a rack or holder, near the operating instructions, for a copy of maintenance manual.

2.7 DC POWER SYTEM

A. General:

1. Provide 48 VDC power system used to provide control power for circuit breakers required for double-ended switchgear; see Section 262315 “Double-Ended Switchgear.

2. System shall consist of number of batteries, battery cabinets, battery chargers, and other components required for proper operation of this system. Interior UPS units are strictly prohibited.

3. System Requirements: Battery shall have number of cells and ampere-hour capacity based upon initial specific gravity of 1.2 at 25 deg C with electrolyte at normal level, and minimum ambient temperature of 15 deg C. Cycle battery before shipment to guarantee rated capacity upon installation. Arrange battery top operate ungrounded.

B. Battery Charger: Static-type rectifier equipped with automatic regulation, and with provision for manual and automatic adjustment of charging rate. Unit shall automatically maintain output voltage within 0.5 percent from no load to rated charger output current, with ac input-voltage variation of plus or minus 10 percent, and input-frequency variation of plus or minus 3 Hz. Other features of charge shall include the following:

1. DC ammeter.

2. DC Voltmeter: Maximum error of 5 percent at full-charge; operates with toggle switch to select between battery and charger voltages.

3. Ground Indication: Two appropriately labeled lights shall indicate circuit ground, connected in series between negative and positive terminals, and with midpoint junction connected to ground by normally open push-button contact.

4. Capacity: Sufficient to supply steady load, float-charge battery between 2.20 and 2.25 V per cell and equalizing charge at 2.3.3 B per Cell.

5. Charging-Rate Switch: Manually operated switch that provides for transferring to higher charging rate. Charger operates automatically after switch operation until reset.

6. Power Supply and Charging: AC power supply is site standard, subject to +/- 10 percent variation in voltage, and +/- 3 Hz variation in frequency.

a. After loss of AC power supply for any interval, charger shall automatically resume charging battery.

b. Charger shall regulate rate of change to prevent damage due to overload, and to prevent fuses or circuit breakers from opening.

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7. Protective Feature: Feature provide current-limiting device or circuit which limits output current to rating of charger, but does not disconnect charger from either battery or AC supply; feature shall protect charger from damage due to overload, including due to short circuit on output terminals.

8. Electrical Filtering: Feature reduces charger’s audible noise to less than 26 dB.

C. Batteries:

1. Battery Type: Sealed, maintenance-free lead acid type.

2. Expected Life: 10-year life when operated and maintained within its specifications.

3. Nominal Battery String Voltage: 48 VDC.

4. Final Discharge Voltage: 42 VDC (1.75 volts per cell).

5. Nominal Float Voltage: 54 VDC (2.25 volts per cell).

6. Battery Recharge Time: Charger shall have capacity to recharge batteries to 90 percent within 12 hours.

7. Battery Circuit Protection: Protection via fuse or circuit breaker.

8. Nominal Battery Ampere Hour (A.H.) Capacity: 100 A.H.; coordinate specified capacity with two switchgear power requirement.

9. System batteries shall be suitable for service at ambient temperature ranging from minus

18 to plus 40 deg C.

2.8 FACTORY TESTING

A. Perform factory test of switchgear.

1. Perform each case identified in Article on SEQUENCE OF OPERATIONS in Section

262315 “Double-Ended Switchgear.”

2. Re-rest all failed test until successful test is achieved.

3. Factory testing shall be witnessed by representative from OBO/PDCS/DE/EE. Provide notification to Contracting Officer/COR within 30 calendar days of scheduled test.

Representative from OBO/PDCS/DE/EE may perform factory inspection at that time as well.

2.9 SOFTWARE

A. At project closeout, submit two electronic copies of PLC software, password, operating software platform, and source code to Contracting Officer/COR for distribution to Post Facility Manager and OBO/CFSM/FAC/PS. PLC software shall facilitate future modifications to power transfer scheme by Post Facility Manager, and operating software platform shall facilitate future reading of PLC software by programmer.

1. In addition, submit two hardcopy manuals of PLC software and code to Contracting

Officer/COR for similar distribution as with software.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 15

PART 3 - EXECUTION

3.1 EXAMINATION

A. Examine elements and surfaces to receive switchgear for compliance with installation tolerances and other conditions affecting performance.

1. Proceed with installation only after unsatisfactory conditions have been corrected.

3.2 INSTALLATION

A. Comply with applicable portions of NECA 400.

B. Anchor switchgear assembly to 100-mm (4-inch), channel-iron floor sill embedded in floor or concrete base and attach by bolting.

1. Sills: Select to suit switchgear; level and grout flush into floor or concrete base.

2. [Design each fastener and support to carry load indicated by seismic requirements and according to seismic-restraint details. See Division 26 Section on vibration and seismic controls for electrical systems for seismic-restraint requirements.]

3. Concrete Bases: 100-mm (4-inch) high, reinforced, with chamfered edges. Extend base no more than 75 mm (3 inches) in all directions beyond maximum dimensions of switchgear unless otherwise indicated or unless required for seismic anchor support.

Construct concrete bases according to Division 26 Section on vibration and seismic controls for electrical systems.

C. Temporary Lifting Provisions: Remove temporary lifting eyes, channels, brackets, and temporary blocking of moving parts from switchgear units and components.

3.3 IDENTIFICATION

A. Identify field-installed conductors, interconnecting wiring, and components; provide warning signs as specified in Division 26 Section on identification for electrical systems.

B. Diagram and Instructions - General:

1. Frame and mount under clear acrylic plastic on front of switchgear.

a. Operating Instructions: Printed basic instructions for switchgear, including control and key-interlock sequences and emergency procedures.

b. System Power Riser Diagrams: Depict power sources, feeders, distribution components, and major loads.

2. Storage for Maintenance: Include a rack or holder, near the operating instructions, for a copy of maintenance manual.

C. Mimic Bus: Continuous mimic bus, arranged in single-line diagram format, using symbols and lettered designations consistent with approved mimic-bus diagram.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 16

1. Mimic-bus segments coordinated with devices in switchgear sections to which applied, to produce concise visual presentation of principal switchgear components and connections.

2. Medium: Painted graphics, as selected or accepted by Contracting Officer/COR.

3. Color: Contrasting with factory-finish background; as selected or accepted by Contracting

Officer/COR from manufacturer's full range.

D. System Power Riser Diagrams: Depict power sources, feeders, distribution components, and major loads. Include as-built data for low-voltage power switchgear and connections as follows:

1. Frame size of each circuit breaker.

2. Trip rating for each circuit breaker.

3. Conduit and wire size for each feeder.

3.4 CONNECTIONS

A. Ground equipment according to Division 26 Section on grounding and bonding for electrical systems.

B. Connect wiring according to Division 26 Section on low-voltage electrical power conductors and cables.

3.5 FIELD QUALITY CONTROL

A. Prepare for acceptance tests as follows:

1. Test insulation resistance for each switchgear bus, component, connecting supply, feeder, and control circuit.

2. Test continuity of each circuit.

B. Manufacturer's Field Service: Engage factory-authorized service representative to perform the following:

1. Inspect switchgear installation, including wiring, components, connections, and equipment.

2. Verify that electrical control wiring installation complies with manufacturer's submittal by means of point-to-point continuity testing. Verify that wiring installation complies with requirements in Division 26 Sections.

3. Complete installation and startup checks according to manufacturer's written instructions.

4. Assist in field testing of equipment including pretesting and adjusting of equipment and components.

5. Report results in writing.

C. Testing: After installing switchgear and after electrical circuitry has been energized, demonstrate product capability and compliance with requirements.

1. Perform each electrical test and visual and mechanical inspection identified in NETA ATS.

Certify compliance with test parameters.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 17

a. Switchgear: Perform tests and inspections stated in NETA, Section 7.1.

b. Circuit Breakers: Perform tests and inspections stated in NETA, Section 7.6.

1) Primary Injection

2) Secondary Injection

c. Protective Relays: Perform tests and inspections stated in NETA, Section 7.9.

d. Instrument Transformers: Perform tests and inspections stated in NETA, Section 7.10.

e. Metering and Instrumentation: Perform tests and inspections stated in NETA, Section 7.11.

f. Ground-Fault Systems: Perform tests and inspections stated in NETA, Section 7.14.

D. Correct malfunctioning units on-site where possible, and retest to demonstrate compliance.

Remove and replace malfunctioning units, and retest as specified above until compliance is demonstrated.

E. Infrared Scanning: After Substantial Completion, but not more than 60 days after Final

Acceptance, perform infrared scan of each switchgear. Remove front and rear panels so joints and connections are accessible to portable scanner. Testing shall include connections and inductive heating of cabling at entrances or where racked in trenches.

1. Follow-up Infrared Scanning: Perform additional follow-up infrared scan of each switchgear 11 months after date of Substantial Completion.

2. Instrument: Use infrared scanning device designed to measure temperature or to detect significant deviations from normal values. Provide calibration record for device.

3. Record of Infrared Scanning: Prepare certified report that identifies switchgear checked and that describes scanning results. Include notation of deficiencies detected, remedial action taken, and observations after remedial action.

3.6 ADJUSTING

A. Set field-adjustable, protective-relay trip characteristics according to results in Section 260573

"Overcurrent Protective Device Coordination Study."

3.7 CLEANING

A. On completion of installation, inspect interior and exterior of switchgear. Remove paint splatters and other spots. Vacuum dirt and debris; do not use compressed air to assist in cleaning. Repair exposed surfaces to match original finish.

3.8 PROTECTION

A. Temporary Heating: Apply temporary heat to switchgear, according to manufacturer's written instructions, throughout periods when switchgear environment is not controlled for temperature and humidity within manufacturer's stipulated service conditions.

LOW-VOLTAGE SWITCHGEAR SECTION 262300 - 18

3.9 STARTUP SERVICES

A. Engage factory-authorized service representative to perform startup service.

B. Verify that switchgear is installed and connected according to the Contract Documents.

C. Verify that electrical control wiring installation complies with manufacturer's submittal by means of point-to-point continuity testing. Verify that wiring installation complies with requirements in

Division 26 Sections.

D. Complete installation and startup checks according to manufacturer's written instructions.

3.10 DEMONSTRATION

A. Engage a factory-authorized service representative to train post maintenance personnel to adjust, operate, and maintain switchgear. Refer to Division 01 Section “Demonstration and Training.”

1. Train on procedures and schedules for general troubleshooting, servicing, and maintaining equipment and schedules, and for equipment isolation and de-energization procedures.

2. Refer to Article on ARC FLASH TRAINING in Section 260573 “Overcurrent Protective

Device Coordination Study” for associated training requirements.

3. Review data in maintenance manuals.

4. Schedule training with the Contracting Officer/COR with at least seven days' advance notice.

END OF SECTION 262300