Attachment 3 - 262315 DOUBLE-ENDED SWITCHGEAR JAN17RR.pdf

JUBA ELECTRICAL UPGRADE DEVELOPMENT July 13, 2020

JUBA SOUTH SUDAN Issued for Bid

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 1

SECTION 262315 - DOUBLE-ENDED SWITCHGEAR

PART 1 - GENERAL

1.1 SUMMARY

A. This Section includes metal-enclosed, low-voltage, power circuit-breaker double-ended switchgear rated 1000 V and less for use in ac systems.

B. Related Sections include the following:

1. Section 230905 “Instrumentation and Controls for HVAC” for building automation system

(BAS) for mechanical systems.

2. Section 260505 “Common Work Results for Electrical, Communications and Electronic

Safety” for facility voltages and safety accessories.

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

4. 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.

5. Section 262300 “Low-Voltage Switchgear.”

6. Section 262313 “Paralleling Switchgear.”

7. Section 263214 “Engine Generators.”

8. Division 26 Section on switchboards.

9. 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 the double-ended switchgear and related equipment.

1. Dimensioned plans, elevations, sections, and details, including required clearances and service space around equipment. Show tabulations of installed devices, equipment features, and ratings. Include the following:

a. Enclosure types and details.

b. Nameplate legends.

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

d. Current rating of buses.

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

f. Mimic-bus diagram.

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

h. Overall dimensions of double-ended switchgear.

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 2

i. Front and section views of double-ended switchgear.

j. Internal wiring diagrams.

k. Electrical characteristics of equipment, including ampere ratings of buses, maximum short circuit withstand ratings and control voltages.

l. Approximate weight of each section of double-ended switchgear and total weight with information required for design of supports and housekeeping pad.

m. Double-ended switchgear elevation with dimensions including available conduit space for each section of double-ended switchgear, front view shipping splits, mounting details and wiring details.

n. Double-ended switchgear device layouts.

o. An anchor bolt plan with dimensions.

p. Isometric of bussing showing ampacities for vertical and horizontal busses.

q. Bus bracing of each section.

r. Arc flash reduction switch.

2. Wiring Diagrams: Provide required wiring diagrams to indicate required power, signal, and control wiring. Wiring diagrams shall differentiate between manufacturer-installed and field-installed wiring details. In addition, wiring diagrams shall show all required relays and interface devices needed for proper operation of power distribution system.

Refer to other Division 26 Sections for interface requirements with this switchgear.

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 double-ended 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. Field Test Reports: Submit written test reports and include the following:

1. Test procedures used.

2. Test results that comply with requirements.

3. Results of failed tests and corrective action taken to achieve test results that comply with requirements.

E. Manufacturer's field service report.

F. Qualification data for testing agency as required in Article on QUALITY ASSURANCE.

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

H. Maintenance Data: For the double-ended switchgear and components to include in maintenance manuals. In addition to requirements specified in Division 01 include the following:

1. Routine maintenance requirements for double-ended switchgear and all installed components.

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

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

I. Maintenance and Operating Manuals:

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 3

1. Contents:

a. Each item of equipment and each system: Include description of unit or system, and component parts. Give function, normal operating characteristics, and limiting conditions. Include performance curves, commercial number of replaceable parts.

b. Provide approved engineering submittals.

c. Provide manufacturer's installation wiring diagrams.

d. Include as-installed color coded wiring diagrams.

e. Operating procedures: Include start-up, break-in, and routine normal operating instructions and sequences. Include regulation, control, stopping, shut-down, and emergency instruction. Include summer, winter, and any special operating instructions.

f. Maintenance requirements: Include routine procedures and guide for trouble-shooting; disassembly, repair and reassembly instructions; and alignment, adjusting, balancing and checking instructions.

g. Include manufacturer's printed installation, operation and maintenance instruction.

h. Provide manufacturer's control diagram for each particular item.

i. Include sequence of operation by controls manufacturer.

j. Provide original manufacturer's parts list, illustration, assembly drawings, and diagrams required for maintenance.

k. Provide list of original manufacturer's spare parts, current prices, and recommended quantities to be maintained in storage.

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 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, but shall protect 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.

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 the National

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

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 4

B. Source Limitations: Obtain double-ended switchgear and switchgear specified in Section 262300

“Low-Voltage Switchgear” through one source from single manufacturer.

C. Product Options: Drawings indicate size, profiles, and dimensional requirements of double-ended switchgear and are based on 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: Conform to the following:

1. American National Standards Institute (ANSI):

a. C37.13 Standard for Low-Voltage AC Power Circuit breakers Used in Enclosures

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

Protectors - Preferred Ratings, Related Requirements, and Application

Recommendations

c. C37.20.1 Metal Enclosed Low-Voltage Power Circuit-Breaker Switchgear

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

Enclosures

e. 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. Certification: Provide certificate of compliance to referenced standards from manufacturer of switchgear.

1.5 DELIVERY, STORAGE, AND HANDLING

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

B. Store double-ended 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.

C. If stored in areas subjected to weather, cover double-ended 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.

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 5

1.6 PROJECT CONDITIONS

A. Product Selection for Restricted Space: Drawings indicate maximum dimensions for switchgear, including clearances between double-ended switchgear, and adjacent surfaces and other items.

Comply with indicated maximum dimensions.

B. 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 <altitude> above sea level.

3. Relative humidity: Up to 100 percent non-condensing.

1.7 COORDINATION

A. Coordinate layout and installation of switchgear and components with other construction, 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.

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

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 MANUFACTURERS

A. Manufacturers: Subject to compliance with requirements, manufacturers offering products that may be incorporated in to the Work include, but are not limited to, the following:

1. Siemens Energy & Automation, Inc.

2. GE Electrical Distribution & Control.

3. Square D Co./Groupe Schneider NA.

4. Cutler-Hammer, Inc.

5. ABB Power T&D Co., Inc.; Distribution Systems Div.

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 6

2.2 GENERAL

A. Provide low-voltage metal-enclosed double-ended switchgear consisting of stationary structure on and within which shall be mounted power air circuit breaker units, overcurrent and other protective devices, buses, barriers, and devices designed, manufactured and tested in accordance with NEMA SG 5 and all referenced ANSI standards as minimum requirements.

B. Arrange double-ended switchgear for connection to the Site Distribution Voltage incoming line through bottom.

C. Double-ended switchgear shall be indoor type and furnished in single line-up assembly.

D. Power double-ended switchgear from same source; power both ends from either generator source or from utility source. Switchgear shall not be powered combination of utility and generator source at the same time. Closed transition is not permitted.

E. Circuit breakers shall be minimum of 800-ampere frame.

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

Division 26 Section on switchboards.

G. Vertical secondary distribution switchgear sections shall align front and rear with depth.

H. Double-ended switchgear shall be complete factory assembled, wired and tested before delivery to site.

I. Place UL labels on required sections of double-ended switchgear in factory before delivery to site.

J. Double-ended switchgear shall be rated for Site Distribution Voltage, with 100 percent neutral.

K. Control wiring within switchgear shall be minimum of 2.5 mm2 insulated copper; larger conductor sizes, if required to perform intended function, shall be furnished by equipment manufacturer.

Conductor insulation shall be suitable for operating temperature of 90 deg C, and shall be one of types approved and listed by NFPA 70 for use in substation construction. Neatly rack and bind control wiring with self locking plastic ties. Make termination of control wiring for internal and external connections in numbered strips, complete with permanent wire markers on each wire.

Connectors used at terminal locations shall be of pressure lug type.

L. Removable rear access panels shall be of hinged type.

M. Completely enclose front with hinged panels covering each breaker, metering, or blank compartment.

N. Provide hinged covers with hinges, latches, and cut-outs where necessary for ventilation, operating mechanism, mechanical trip, and position indication.

O. Each compartment, such as circuit breaker, metering, current transformer, bus and cable compartments of the total assembly shall be completely and totally isolated on top, bottom, except cable compartments, and sides from all other compartments by suitable metal barriers.

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P. Arrange separate steel breaker compartments in tiers in each unit section. Provide barrier to divide each unit section vertically into compartments.

Q. Provide engraved nameplates for main, and feeder circuits, including control fuses and indicating lights and instruments. Nameplates shall give item designation, circuit number, name of load servicing, frame ampere rating, sensor ampere rating, and trip ampere rating. Secure nameplates fastened to equipment with screws. Provide white laminated nameplates with black letters engraved, approximately 50 mm by 75 mm with 6 mm high lettering.

R. Provide master nameplate giving double-ended switchgear designation, voltage, ampere rating, bracing, manufacturer's name, identification, reference and serial numbers.

S. Arrange double-ended switchgear for service as indicated on Drawings complete with spares, spaces and circuit protective devices with capacities indicated.

T. Fabricate structure so that extension of double-ended switchgear may be accomplished in future by addition of new cubicles and by simple splice plates on horizontal bus. Where "space" is indicated on Drawings, space shall be completely bussed and provided with breaker draw-out mechanism for future acceptance of breaker and its instrumentation.

U. Installation and connection of switchgear shall not require removal or disassembly of any factory mounted stationary high voltage devices.

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

W. Arc Flash Maintenance Reduction 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.

2.3 ENCLOSURE

A. Enclosure shall be listed under UL-1558 "Metal-Enclosed Low-Voltage Power Circuit Breaker

Switchgear." Switchgear assembly shall be UL listed and labeled.

B. Completely isolate each breaker compartment from other breaker compartments by grounded metal barriers.

C. To the extent practicable, fabricate each breaker compartment door without ventilation slots for operator safety. If ventilation slots are required, then they shall be located in such a way prevent possibility of metal objects being inserted through them and easily contacting energized parts.

D. Door of each breaker compartment shall remain closed when racking the breaker to any of its three positions (disconnected, test, connected) unless double steel barrier exists between operating personnel and breaker mechanism/live parts which make it safe to operate breaker with outer steel door open.

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E. Each section enclosure shall consist of three compartments: Breaker compartment located in the front, bus compartment located in center, and cable compartment located at rear. Isolate breaker compartment and bus compartment from each other by barriers.

F. Breaker compartment shall contain drawout circuit breaker elements. Active and spare breaker cells shall be complete with circuit breaker, breaker drawout mechanism and all instrumentation.

G. Bus compartment shall contain section riser and the main cross bus.

H. Size cable compartment to accommodate incoming and outgoing cables, including future cables associated with future breakers required within each vertical switchgear section.

I. Mount integral, roll along breaker lifting device on top of distribution switchgear enclosure.

J. All secondary circuit breakers shall be top or bottom fed.

2.4 FABRICATION

A. Finish: IEEE C37.20.1 “Metal Enclosed Low-Voltage Power Circuit-Breaker Switchgear,” manufacturer's standard gray finish over a rust-inhibiting primer on phosphatizing-treated metal surfaces.

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

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

1. Incoming-line pull sections.

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

2.5 BUS STRUCTURE

A. 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.

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 9

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 Site Distribution 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.

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 Site Distribution Voltage.

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.

2.6 COMPONENTS

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

DOUBLE-ENDED SWITCHGEAR SECTION 262315 - 10

1. Potential Transformers: Secondary-voltage rating of Utilization Voltage or Control

Voltage, 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.

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.

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

4. Unit shall have built-in communications capability which allows communication to

Building Automation System (BAS). It shall be possible to monitor and trend electrical demand and energy use, as well as other features specified above in switch-selectable digital display, through BAS.

5. Provide unit at each circuit breaker (mains, ties and feeders).

C. Relays: Comply with IEEE C37.90, types and settings as indicated, with test blocks and plugs.

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

E. Provide controllers or relays required for implementation of applicable Article on SEQUENCE

OF OPERATION in this Section. Relays shall operate on DC control voltage. "Sequence of operation" involves start and stop of multiple generators and open and close of multiple circuit breakers. Provide power system controller for controlling essential bus main breaker, utility bus main breaker, and tie breaker between essential and utility buses. Controller shall use programmable logic controller (PLC); electromagnetic control relays are not permitted. Provide duplicate “hot standby” PLC in same enclosure as primary. Changeover shall require only moving keyed wiring connects and resetting processor. Provide DC power system, including required batteries, charger, cabinet, and other accessories needed to control all electrically operated circuit breakers for implementation of "sequence of operation" as described in this

Section. Provide DC power from this system to switchgear as needed to operate all circuit breakers.

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F. Upon loss of utility power on incoming side of circuit breaker CB1, circuit breaker CB1 shall trip after adjustable time delay (0-30 seconds); set at 15 seconds and field verify setting. Time delay setting shall be higher than time required for generator to come on line and be ready to accept loads. Loss of voltage sensing is required to comply with the Sequence of Operation as defined in applicable Article on SEQUENCE OF OPERATION.

G. Upon loss of utility power on incoming side of circuit breaker CB3, circuit breaker CB3 shall trip after adjustable time delay (0-30 seconds); set at 15 seconds and field verify setting. Time delay setting shall be higher than time required for generator to come on line and be ready to accept loads. Loss of voltage sensing is required to comply with applicable Article on SEQUENCE OF

OPERATION.

2.7 CIRCUIT BREAKERS

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

Used in Enclosures.”

B. Main, tie and feeder breakers shall be drawout type capable of interrupting available short circuit.

C. Main, tie and feeder breakers shall be rated for 100 percent of their continuous ampere rating.

D. Main, tie and feeder breakers shall be rated for minimum of 65,000 amperes symmetrical.

E. Breakers trip mechanism shall be of solid state trip as specified for main breakers and feeder breakers.

F. Breakers shall be UL listed for application in intended enclosure.

G. Provide breakers with true, stored energy mechanism providing maximum of 6 cycle closing.

Energy required for closing breaker shall be completely stored and held in readiness pending release to close action. Mechanism shall be charged by constant force manual charging lever.

Breaker shall have multiple charge/close provisions providing the following possible sequence:

Charge - close - recharge - open - close - open. As safety feature, provisions shall be available to manually discharge stored energy without closing breaker.

H. Breaker control face plate shall include color coded visual indicators to indicate contact "open" and "closed" positions, and to indicate mechanism "charge" and "discharged" positions. Provide local control pushbuttons for opening the breaker.

I. Provide breakers with self-aligning fingers to engage line and load primary disconnects. Drawout mechanism shall firmly support breaker from fully connected to fully disconnected position.

J. Provide selective override circuit on breakers having short time adjustments that will allow breaker to be applied at its maximum interrupting rating while providing full selectivity up to its rms symmetrical short-time rating. This selective override circuit shall allow breaker to ride through fully offset (asymmetrical) fault equal to its rms symmetrical short-time rating in system having an X/R ratio of 6.6 with maximum single phase peak current of 2.3 times the rms symmetrical short time rating.

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K. Locate instrumentation required for each breaker in one place in compartment to eliminate cross-hinge wiring. Instrumentation shall include control fuse blocks, blown fuse lock-out relays, etc., as required for breaker operation.

L. Provide primary disconnect shutter to form protective barrier in front of energized primary disconnects when breaker is moved to its disconnected position.

M. Insulate and support vertical buses provide insulation between adjacent bus bars.

N. Main and Tie Breakers:

1. Breakers shall be electrically operated, sized as shown on the drawings. Control power shall be provided from the DC power system.

2. Breakers shall have high endurance characteristics as listed in the ANSI Standards.

Breakers shall be equipped with field replaceable contacts.

3. Provide complete system selective coordination using single, self-contained programmer having harmonic restraint characteristics with the following nine function solid state trip mechanism:

a. Current setting.

b. Long time pickup.

c. Long time delay.

d. Short time pickup.

e. Short time delay (l2t).

f. Ground fault pick-up.

g. Ground fault delay (l2t).

h. Fault trip annunciator.

4. Make adjustments of solid state trip mechanism using dial type switches as part of solid state trip mechanism described in complete system selective coordination above.

5. Provide fault trip annunciator with up to three visual indicators to indicate automatic trip point mode of breaker:

a. Overload.

b. Short circuit.

c. Ground fault.

6. Provide ground fault protection as part of solid state trip mechanism.

7. Breakers shall have adjustable trip setting.

8. Provide main breaker with phase failure/phase reverse relay.

O. Feeder Breakers:

1. Breakers shall be 100 percent rated.

2. Breakers shall be manually operated, sized as indicated on Drawings.

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3. Equip breakers with nine function solid state trip mechanism with the following adjustments:

a. Current setting.

b. Long time pickup.

c. Long time delay.

d. Short time pickup.

e. Short time delay (l2t).

f. High range instantaneous pick-up.

g. Ground fault pick-up.

h. Ground fault delay (l2t).

i. Fault trip annunciator.

4. Make adjustments of solid state trip mechanism using dial type switches as part of solid state trip mechanism described in complete system selective coordination above.

5. Provide fault trip annunciator with up to three visual indicators to indicate automatic tripping mode of breaker:

a. Overload.

b. Short circuit.

c. Ground fault.

6. Provide ground fault protection as part of solid state trip mechanism.

7. Breakers of same frame shall be interchangeable.

8. Breakers 800 amperes frame shall have adjustable trip setting between 100 amperes and

800 amperes.

9. Breakers 1600 amperes frame shall have adjustable trip setting between 300 amperes and

1600 amperes.

P. 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, provide quantity indicated. Each consists of two Type "a" and two Type "b" stages (contacts) wired through secondary disconnect devices to terminal block in stationary housing.

Q. Drawout Features: Equip circuit-breaker mounting assembly with 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: An 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.

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3. Provide trip/close control switch for circuit breakers “CB1”, “CB2”, “CB3”, “CB4”, “CBA”, “CBB”, and “CBC”.

4. Provide single “HAND/AUTO” selector switch.

5. When circuit breakers “CB1”, “CB2”, “CB3”, “CB4”, “CBA”, “CBB”, and “CBC” are in the test position, operator shall be able to open and close circuit breakers through their associated trip/close control switch, when position of “HAND/AUTO” selector switch is in “HAND” mode only.

6. When circuit breakers “CB1”, “CB2”, “CB3”, “CB4”, “CBA”, “CBB”, and “CBC” are in connect position, operator shall be able to open and close circuit breakers through their associated trip/close control switch only when operating in “HAND” mode. Operator shall not be able to open or close circuit breakers when operating in “AUTO” mode. Circuit breakers shall be capable of opening and closing automatically when “HAND/AUTO” selector switch is in “AUTO” mode.

a. [For close operation in the “HAND” mode refer to Article on SEQUENCE OF

OPERATION: UTILITY/ATS.]

R. Include provisions for installing at least three padlocks on each circuit breaker to secure its enclosure and prevent movement of drawout mechanism.

S. Electric Trip/Close Control Switch: One for each electrically operated circuit breaker.

T. Indicating Lights: To indicate circuit breaker is open or closed, for circuit breakers “CB1”, “CB2”, “CB3”, “CB4”, “CBA”, “CBB”, and “CBC” (green for open, red for closed).

2.8 DC POWER SYSTEM

A. General:

1. Provide 48 VDC power system to be used to provide control power to required circuit breakers of double-ended switchgear specified in other Division 26 Sections.

2. System shall consist of required number of batteries, battery cabinet, battery charger(s) and other components required for proper operation of this system.

B. Battery Charger:

1. Battery charger shall be voltage-regulated type.

2. Size battery charger with ampere rating sufficient to meet simultaneous demand of required switchgear loads and self-discharge losses of batteries.

C. Cabinet:

1. Mount components in cabinet, with footprint approximately 0.6 m deep by 1.5 m high.

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

D. Batteries:

1. Battery Type: Batteries shall be of sealed, maintenance free lead acid type.

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

3. Nominal Battery String Voltage: 48 VDC

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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 capacity in 12 hours.

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

8. Nominal Battery Ampere Hour (A.H.) Capacity: 100 A.H. Coordinate specified capacity with two switchgears power requirements.

2.9 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: 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.

2.10 IDENTIFICATION

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

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

2. Medium: Painted graphics.

3. Color: Contrasting with factory-finish background.

[NOTES: The following sequences of operations are for three individual scenarios for embassy site. Option selected for particular embassy site is identified in other contract documents such as a selected option in Section C of the RFP. Three options are UTILITY/ATS, UTILITY/PARALLELING SWITCHGEAR and PRIME/

PARALELLING SWITCHGEAR.

Section following three options is required for NOB switchgear and shall not be deleted.

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Edit this specification section for individual site-specific requirements utilizing one of the following three sequences.]

2.11 SEQUENCE OF OPERATION: UTILITY/ATS

A. The following cases No. 1 through No. 10 shall be implemented when circuit breakers “CB1”, “CB2”, “CB3”, “CB4” and “CBM” are operating in the “AUTO” mode. Circuit breakers “CB1”, “CB2” and “CB3” shall be electrically interlocked as such that the tie circuit breaker “CB2” shall close only if circuit breakers “CB1” or “CB3” are open. Refer to the one-line diagram for designation of circuit breakers, Generators and transformers.

B. Case No. 1: Normal power is available from the utility company.

1. CBM (SWG1 main breaker) is closed.

2. CB1 (essential bus main breaker) shall be in the closed position.

3. CB2 (tie breaker between essential and utility buses) shall be in the open position.

4. CB3 (utility bus main breaker) shall be in the closed position.

5. CB4 (breaker between utility bus No. 1 and HVAC bus) shall be in the closed position.

C. The following cases No. 2 through No. 10 shall be implemented Monday through Friday from

6:00am to 8:00pm. It shall be possible to adjust the time schedule if required.

D. Case No. 2: In the event of loss of power from the utility company, or failure of any of the medium voltage feeders or the service transformer or the automatic voltage regulator, and both E and U are available, the following sequence shall be initiated:

1. CBM shall open.

2. Generator "E" (essential) shall start automatically.

3. Generator "U" (utility) shall start automatically.

4. ATS-E (essential) transfers service to E.

5. ATS-U (utility) transfers service to U.

6. Power service to the essential and utility distribution switchgear is restored.

7. Generators E and U shall be ready to accept loads in less than 10 seconds.

E. Case No. 3: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No. 2), the following sequence shall be initiated:

1. CBM shall close.

2. CB1 shall remain in the closed position.

3. CB2 shall remain in the open position.

4. CB3 shall remain in the closed position.

5. CB4 shall remain in the closed position.

6. ATS-E shall transfer service back to utility supply, from Generator E.

7. ATS-U shall transfer service back to utility supply, from Generator U.

8. Generators E and U shall continue to run (cool down) for a period of time as specified in

Section 263214, “Engine Generators” before shutting down.

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F. Case No. 4: In the event of loss of power from the utility company, or failure of any of the medium voltage feeders or the service transformer or the automatic voltage regulator, and

Generator E is available, but Generator U is not available, the following sequence shall be initiated:

1. CBM shall open.

2. Generator E shall start automatically.

3. ATS-E shall transfer service to E.

4. CB1 shall remain in the closed position.

5. CB3 shall open, after a specified time delay. (Refer to Article on COMPONENTS).

6. CB4 shall open.

7. CB2 shall close, after both CB3 and CB4 are open.

8. ATS-U will not transfer service to an unavailable source.

9. Generator E shall be ready to accept loads in less than 10 seconds.

G. Case No. 5: In the event that Generator U becomes available after the implementation of the sequence of operation listed under Case No. 4, the following sequence shall be initiated:

1. CBM is open.

2. Generator U shall start automatically.

3. ATS-U shall transfer service to U.

4. CB2 shall open, after detection of voltage on the line side of CB3.

5. CB3 shall close, after CB2 is open.

6. CB4 shall close.

7. Generator U shall be ready to accept loads in less than 10 seconds.

H. Case No. 6: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No. 4), the following sequence shall be initiated:

1. After specified time delay, CBM shall close.

2. CB1 shall remain in the closed position.

3. ATS-U shall transfer service back to utility supply, from Generator U, if required.

4. ATS-E shall transfer service back to utility supply, from Generator E.

5. CB2 shall open, after detection of voltage on the line side of CB3.

6. CB3 shall close, after CB2 is open.

7. CB4 shall close.

8. Generators E shall continue to run (cool down) for a period of time as specified in Section

263214 ”Engine Generators” before shutting down.

I. Case No. 7: In the event of loss of power from the utility company, or failure of any of the medium voltage feeders or the service transformer or the automatic voltage regulator, and

Generator E is not available, but Generator U is available, the following sequence shall be initiated:

1. CBM shall open.

2. Generator U shall start automatically.

3. ATS-U shall transfer service to Generator U.

4. CB3 shall remain in the closed position.

5. CB1 shall open, after a specified time delay.

6. CB4 shall open.

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7. CB2 shall close, after both CB1 and CB4 are open.

8. ATS-E will not transfer service to an unavailable source.

9. Generator U shall be ready to accept loads in less than 10 seconds.

J. Case No. 8: In the event that Generator E becomes available after the implementation of the sequence of operation listed under Case No. 7, the following sequence shall be initiated:

1. CBM is open.

2. Generator E shall start automatically.

3. ATS-E shall transfer service to E.

4. CB2 shall open, after detection of voltage on the line side of CB1.

5. CB1 shall close, after CB2 is open.

6. CB4 shall close.

7. Generator E shall be ready to accept loads in less than 10 seconds.

K. Case No. 9: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No. 7), the following sequence shall be initiated:

1. CBM shall close.

2. CB3 shall remain in the closed position.

3. ATS-E shall transfer service back to utility supply, from Generator E, if required.

4. ATS-U shall transfer service back to utility supply, from Generator U.

5. CB2 shall open, after detection of voltage on the line side of CB1.

6. CB1 shall close, after CB2 is open.

7. CB4 shall close.

8. Generators U shall continue to run (cool down) for a period of time as specified in this section before shutting down.

L. Case No. 10: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No.

5 and No. 8), the following sequence shall be initiated:

1. After a specified time delay, CBM shall close.

2. CB1 shall remain in the closed position.

3. CB2 shall remain in the open position.

4. CB3 shall remain in the closed position.

5. CB4 shall remain in the closed position.

6. ATS-E shall transfer service back to utility supply, from Generator E.

7. ATS-U shall transfer service back to utility supply, from Generator U.

8. Generators E and U shall continue to run (cool down) for a period of time as specified in

Section 263214 ”Engine Generators” before shutting down.

M. The following Cases No. 11 through No. 15 shall be implemented Monday through Friday from

8:00pm to 6:00am and Saturday and Sunday. It shall be possible to adjust the time schedule if required.

N. Case No. 11: In the event of loss of power from the utility company, or failure of any of the medium voltage feeders or the service transformer or the automatic voltage regulator, and both

Generators E and U are available, the following sequence shall be initiated:

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1. CBM shall open.

2. CB1 shall remain in the closed position.

3. Generator E (essential) shall start automatically.

4. ATS-E (essential) shall transfer service to Generator E.

5. CB3 shall open, after a specified time delay. (Refer to Article on COMPONENTS).

6. CB2 shall close, after CB3 is open.

7. The loads connected to Generator E shall be continuously monitored. It shall be possible, if required, for the operator to manually connect the load bank to the Generator with the required load steps needed to ensure that the Generator is at least loaded to 50 percent of its rating.

8. ATS-U (utility) shall not transfer service to Generator U.

9. Power service to the essential and utility distribution switchgear is restored.

10. Generator "E" shall be ready to accept loads in less than 10 seconds.

O. Case No. 12: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No.

11), the following sequence shall be initiated:

1. After a specified time delay, CBM shall close.

2. CB1 shall remain in the closed position.

3. CB2 shall open, after detection of voltage on the line side of CB3.

4. CB3 shall close, after CB2 is open.

5. CB4 shall remain in the closed position.

6. ATS-E shall transfer service back to utility supply, from Generator E.

7. Power service to the essential and utility distribution switchgear is restored.

8. Load bank, if connected, shall be disconnected.

9. Generator E shall continue to run (cool down) for a period of time as specified in Section

263214 “Engine Generators” before shutting down.

P. Case No. 13: In the event of loss of power from the utility company, or failure of any of the medium voltage feeders or the service transformer or the automatic voltage regulator, and

Generator E is not available, but Generator U is available, the following sequence shall be initiated:

1. CBM shall open.

2. CB3 shall remain in the closed position.

3. Generator U shall start automatically.

4. ATS-U (utility) shall transfer service to Generator U.

5. CB1 shall open, after a specified time delay. (Refer to Article on COMPONENTS).

6. CB4 shall remain in the closed position.

7. CB2 shall close, after CB1 is open.

8. The loads connected to Generator U shall be continuously monitored. It shall be possible, if required, for the operator to manually connect the load bank to the Generator with the required load steps needed to ensure that the Generator is at least loaded to 50 percent of its rating.

9. ATS-E shall not transfer service to E.

10. Power service to the essential and utility distribution switchgear is restored.

11. Generator U shall be ready to accept loads in less than 10 seconds.

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Q. Case No. 14: In the event that Generator E becomes available after the implementation of the sequence of operation listed under Case No. 13, no changes to the sequence of operation shall be made.

R. Case No. 15: When power from the utility company is restored or when the medium voltage feeder or the service transformer or the automatic voltage regulator is back in service (Case No.

13), the following sequence shall be initiated:

1. CBM shall close.

2. CB3 shall remain in the closed position.

3. CB2 shall open, after detection of voltage on the line side of CB1.

4. CB1 shall close, after CB2 is open.

5. CB4 shall remain in the closed position.

6. ATS-U shall transfer service back to utility supply, from Generator U.

7. Power service to the essential and utility distribution switchgear is restored.

8. Generator U shall continue to run (cool down) for a period of time as specified in Section

263214 “Engine Generators” before shutting down.

S. The following cases No. 16 through No. 26 shall be implemented when circuit breakers CB1 or

CB2 or CB3 are not operating under the “AUTO” mode and as such the ‘HAND” mode will have to be implemented, and during Monday through Friday from 6:00am to 8:00pm. It shall be possible to adjust the time schedule if required. Circuit breakers CB1, CB2 and CB3 shall be electrically interlocked as such that the tie circuit breaker CB2 shall close only if circuit breakers

CB1 or CB3 are open.

T. Case No. 16: When utility or Generator power is available at the line side of circuit breakers CB1 and CB3, but the two breakers not being able to close under “AUTO” mode due to a malfunction in the automatic control scheme, the following sequence shall be initiated:

1. Switch to the “HAND” mode the selector switch.

2. Trip open CB2 through the trip/close control switch, if it is closed.

3. Close circuit breakers CB1 and CB3 through the trip/close control switch.

4. CB4 shall remain closed.

U. Case No. 17: When utility power is available at the line side of circuit breakers CB1 and CB3, but circuit breaker CB1 is not being able to close under “AUTO” mode due to a malfunction in the automatic control scheme, the following sequence shall be initiated:

1. Switch to the “HAND” mode the…