USACE / NAVFAC / AFCESA / NASA UFGS-26 23 00 (July 2006)
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Preparing Activity: NAVFAC Superseding
UFGS-26 23 00 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 26 23 00
SWITCHBOARDS AND SWITCHGEAR
07/06
NOTE: This guide specification covers the requirements for free standing deadfront
switchboard assemblies rated 6000 amperes or less, 600 volts or less, and metal-enclosed
low-voltage power circuit-breaker switchgear assemblies in either interior or
exterior locations. Rename the section appropriately if this section is used
to specify only switchboards or only switchgear. Use Section 26 20 00 INTERIOR
DISTRIBUTION SYSTEM, for power and distribution panelboards rated 1200 amperes
or less and consisting of only group mounted stationary molded case circuit
breakers and fusible or nonfusible switches designed to be placed in a cabinet
or cutout box.
When the proposed switchboard or switchgear is connected to a secondary unit
substation, coordinate with Section 26 11 16 SECONDARY UNIT SUBSTATIONS.
This specification is not intended to be used for generator control switchboards
without extensive modification and coordination with applicable diesel engine-generator
guide specifications.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestion on this specification are welcome and should be directed
to the technical proponent of the specification. A listing of the technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
NOTE: The following information should be indicated on the project drawings
or specified in the project specifications:
1. Single-line diagram showing buses and interrupting devices with interrupting
capacities; current transformers with ratings; instruments and meters required;
and description of instruments and meters.
2. Location, space available, arrangement, and elevations of switchboards or switchgear.
3. Grounding plan.
4. Type and number of cables, size of conductors for each power circuit, and
point of entry (top or bottom).
5. Special conditions, such as altitude, temperature and humidity, exposure
to fumes, vapors, dust, and gases; and seismic requirements.
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to in the text by the basic designation only.
[AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)ANSI C12.15(1990) Solid-State Demand Registers for Electromechanical Watthour MetersANSI C39.1(1981; R 1992) Requirements for Electrical Analog Indicating Instruments][ASTM INTERNATIONAL (ASTM)ASTM A 123/A 123M(2008) Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel ProductsASTM A 153/A 153M(2005) Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel HardwareASTM A 167(1999; R 2004) Standard Specification for Stainless and Heat-Resisting Chromium-Nickel Steel Plate, Sheet, and StripASTM A 653/A 653M(2008) Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip ProcessASTM A 780(2001; R 2006) Standard Practice for Repair of Damaged and Uncoated Areas of Hot-Dip Galvanized CoatingsASTM D 149(1997a; R 2004) Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power FrequenciesASTM D 1535(2008) Specifying Color by the Munsell SystemASTM D 709(2001; R 2007) Laminated Thermosetting Materials][INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE)IEEE C12.16(1991) Solid-State Electricity MetersIEEE C2(2007; Errata 2007; INT 2008) National Electrical Safety CodeIEEE C37.13(1990; R 1995) Standard for Low-Voltage AC Power Circuit Breakers Used in EnclosuresIEEE C37.20.1(2002; Addenda A 2005; Addenda B 2006; R 2007) Standard for Metal-Enclosed Low-Voltage Power Circuit-Breaker SwitchgearIEEE C37.90.1(2002; Errata 2003; Errata 2004) Surge Withstand Capability (SWC) Tests for Relays and Relay Systems Associated with Electric Power ApparatusIEEE C57.12.28(2005) Standard for Pad-Mounted Equipment - Enclosure IntegrityIEEE C57.12.29(2005) Pad-Mounted Equipment - Enclosure Integrity for Coastal EnvironmentsIEEE C57.13(2008) Standard Requirements for Instrument TransformersIEEE Std 100(2000) The Authoritative Dictionary of IEEE Standards TermsIEEE Std 81(1983) Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials of a Ground System (Part 1)Normal Measurements][INTERNATIONAL ELECTRICAL TESTING ASSOCIATION (NETA)NETA ATS(2003) Acceptance Testing Specifications][NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA C12.1(2008) Electric Meters; Code for Electricity MeteringNEMA C12.10(2004) Physical Aspects of Watthour MetersNEMA C12.4(1984; R 2002) Mechanical Demand RegistersNEMA ICS 6(1993; R 2006) Standard for Industrial Controls and Systems EnclosuresNEMA LI 1(1998) Industrial Laminated Thermosetting ProductsNEMA PB 2(2006) Deadfront Distribution SwitchboardsNEMA PB 2.1(2007) General Instructions for Proper Handling, Installation, Operation and Maintenance of Deadfront Distribution Switchboards Rated 600 Volts or LessNEMA ST 20(1992; R 1997) Standard for Dry-Type Transformers for General Applications][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 70(2007; AMD 1 2008) National Electrical Code - 2008 Edition][UNDERWRITERS LABORATORIES (UL)UL 1558(1999; Rev thru Mar 2006) Metal-Enclosed Low-Voltage Power Circuit Breaker SwitchgearUL 198M(2003; Rev thru Oct 2007) Mine-Duty FusesUL 467(2007) Standard for Grounding and Bonding EquipmentUL 489(2002; Rev thru Jun 2006) Standard for Molded-Case Circuit Breakers, Molded-Case Switches and Circuit-Breaker EnclosuresUL 512(1993; Rev thru Jan 2008) FuseholdersUL 891(2005) Dead-Front Switchboards]1.2 RELATED REQUIREMENTS
Section 26 08 00 APPARATUS INSPECTION AND TESTING applies to this section, with the additions and modifications
specified herein.
1.3 DEFINITIONS
a. Unless otherwise specified or indicated, electrical and electronics terms used in these specifications,
and on the drawings, shall be as defined in IEEE Std 100.
1.4 SUBMITTALS
NOTE: Choose between switchboards and switchgear in brackets throughout this
specification. Modify appropriately if both are used in a job.
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] Submit the following
in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
[Switchboard][Switchgear] Drawings[; G][; G, [_____]]
Include wiring diagrams and installation details of equipment indicating proposed location,
layout and arrangement, control panels, accessories, piping, ductwork, and other items that
must be shown to ensure a coordinated installation. Wiring diagrams shall identify circuit
terminals and indicate the internal wiring for each item of equipment and the interconnection
between each item of equipment. Drawings shall indicate adequate clearance for operation, maintenance,
and replacement of operating equipment devices. Submittals shall include the nameplate data,
size, and capacity. Submittals shall also include applicable federal, military, industry, and
technical society publication references.
SD-03 Product Data
[Switchboard][Switchgear][; G][; G, [_____]]
SD-06 Test Reports
[Switchboard][Switchgear] design tests[; G][; G, [_____]]
[Switchboard][Switchgear] production tests[; G][; G, [_____]]
Acceptance checks and tests[; G][; G, [_____]]
SD-10 Operation and Maintenance Data
[Switchboard][Switchgear] Operation and Maintenance, Data Package 5[; G][; G, [_____]]
SD-11 Closeout Submittals
Assembled Operation and Maintenance Manuals[; G][; G, [_____]]
Equipment Test Schedule[; G][; G, [_____]]
Request for Settings[; G][; G, [_____]]
1.5 QUALITY ASSURANCE
1.5.1 [Switchboard][Switchgear] Product Data
Each submittal shall include manufacturer's information for each component, device and accessory provided with
the [switchboard][switchgear] including:
a. Circuit breaker type, interrupting rating, and trip devices, including available settings
b. Manufacturer's instruction manuals and published time-current curves (on full size logarithmic paper)
of the main secondary breaker and largest secondary feeder device.
1.5.2 [Switchboard][Switchgear] Drawings
Drawings shall include, but are not limited to the following:
a. One-line diagram including breakers[, fuses][, current transformers, and meters]
b. Outline drawings including front elevation, section views, footprint, and overall dimensions
c. Bus configuration including dimensions and ampere ratings of bus bars
d. Markings and NEMA nameplate data[, including fuse information (manufacturer's name, catalog number,
and ratings)]
e. Circuit breaker type, interrupting rating, and trip devices, including available settings
f. Three-line diagrams and elementary diagrams and wiring diagrams with terminals identified, and indicating
prewired interconnections between items of equipment and the interconnection between the items.
g. Manufacturer's instruction manuals and published time-current curves (on full size logarithmic paper)
of the main secondary breaker and largest secondary feeder device. These shall be used by the designer
of record to provide breaker settings that will ensure protection and coordination are achieved.
[h. Provisions for future extension.]
1.5.3 Regulatory Requirements
In each of the publications referred to herein, consider the advisory provisions to be mandatory, as though the
word, "shall" had been substituted for "should" wherever it appears. Interpret references in these publications
to the "authority having jurisdiction," or words of similar meaning, to mean the Contracting Officer. Equipment,
materials, installation, and workmanship shall be in accordance with the mandatory and advisory provisions of
NFPA 70 unless more stringent requirements are specified or indicated.
1.5.4 Standard Products
Provide materials and equipment that are products of manufacturers regularly engaged in the production of such
products which are of equal material, design and workmanship. Products shall have been in satisfactory commercial
or industrial use for 2 years prior to bid opening. The 2-year period shall include applications of equipment
and materials under similar circumstances and of similar size. The product shall have been on sale on the commercial
market through advertisements, manufacturers' catalogs, or brochures during the 2-year period. Where two or
more items of the same class of equipment are required, these items shall be products of a single manufacturer;
however, the component parts of the item need not be the products of the same manufacturer unless stated in this
section.
1.5.4.1 Alternative Qualifications
Products having less than a 2-year field service record will be acceptable if a certified record of satisfactory
field operation for not less than 6000 hours, exclusive of the manufacturers' factory or laboratory tests, is
furnished.
1.5.4.2 Material and Equipment Manufacturing Date
Products manufactured more than 3 years prior to date of delivery to site shall not be used, unless specified
otherwise.
1.6 MAINTENANCE
1.6.1 [Switchboard][Switchgear] Operation and Maintenance Data
Submit Operation and Maintenance Manuals in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
1.6.2 Assembled Operation and Maintenance Manuals
Manuals shall be assembled and bound securely in durable, hard covered, water resistant binders. The manuals
shall be assembled and indexed in the following order with a table of contents. The contents of the assembled
operation and maintenance manuals shall be as follows:
a. Manufacturer's O&M information required by the paragraph entitled "SD-10, Operation and Maintenance
Data".
b. Catalog data required by the paragraph entitled, "SD-03, Product Data".
c. Drawings required by the paragraph entitled, "SD-02, Shop Drawings".
d. Prices for spare parts and supply list.
[e. Information on metering]
f. Design test reports
g. Production test reports
[1.6.3 Spare Parts
NOTE: Spare parts are specified in Section 01 78 23 OPERATION AND MAINTENANCE
DATA for Navy projects. Do not use this paragraph for Navy projects.
Edit as required if additional spare parts are required for a specific project.
Spare parts shall be furnished as specified below. All spare parts shall be of the same material and workmanship,
shall meet the same requirements, and shall be interchangeable with the corresponding original parts furnished.
a. 2 - Fuses of each type and size.
[b. [________________________________]]
]1.7 WARRANTY
The equipment items shall be supported by service organizations which are reasonably convenient to the equipment
installation in order to render satisfactory service to the equipment on a regular and emergency basis during
the warranty period of the contract.
PART 2 PRODUCTS
2.1 PRODUCT COORDINATION
NOTE:
For Army projects, refer to Section 33 70 02.00 10 UNDERGROUND TRANSMISSION
AND DISTRIBUTION SYSTEM, UNDERGROUND; typical throughout this specification.
NOTE: When project is designated to be designed to Antiterrorism Construction
Standards, the electrical design must address limiting critical infrastructure
damage. If project scope does not address special (Switchboard) (Switchgear)
requirements, designer should check with Project Manager to see if, as a minimum,
Seismic Zone 1 criteria should be incorporated.
Products and materials not considered to be[ switchboards][ or][ switchgear] and related accessories are specified
in[ Section 33 71 02.00 20 UNDERGROUND UNDERGROUND TRANSMISSION AND DISTRIBUTION,][ Section 33 70 02.00 10 UNDERGROUND
TRANSMISSION AND DISTRIBUTION SYSTEM, UNDERGROUND,] and Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM.
2.2 [SWITCHBOARD][SWITCHGEAR]
[NEMA PB 2 and UL 891][IEEE C37.20.1 and UL 1558].
2.2.1 Ratings
The voltage rating of the [switchboard][switchgear] shall be [480Y/277][208Y/120][125][_____] volts [AC][DC],
[2][3][4]-wire [[single][3] phase][as indicated]. The continuous current rating of the main bus shall be [_____
amperes][as indicated]. The short-circuit current rating shall be [_____ rms symmetrical amperes][as indicated].
The [switchboard][switchgear] shall be UL listed and labeled[ for its intended use][ as service entrance equipment].
2.2.2 Construction
[Switchboard][Switchgear] shall consist of vertical sections bolted together to form a rigid assembly and shall
be [rear][front and rear] aligned[ as indicated]. All circuit breakers shall be front accessible.[ Rear aligned
switchboards shall have front accessible load connections.][ Front and rear aligned switchboards shall have
rear accessible load connections.][ Compartmentalized [switchboards][switchgear] shall have vertical insulating
barriers between the front device section, the main bus section, and the cable compartment[ with full front to
rear vertical insulating barriers between adjacent sections].] Where indicated, "space for future" or "space"
shall mean to include bus, device supports, and connections. Provide insulating barriers in accordance with
NEMA LI 1, Type GPO-3, 6.35 mm (0.25 inch) 0.25 inch minimum thickness. Apply moisture resistant coating to
all rough-cut edges of barriers. Switchboard shall be completely factory engineered and assembled, including
protective devices and equipment indicated with necessary interconnections, instrumentation, and control wiring.
2.2.2.1 Enclosure
NOTE: Choose the level of corrosion protection required for the specific project
location. Use galvanized steel in most indoor applications. Use stainless
steel bases for most outdoor applications. In less corrosive environments,
galvanized steel can be included as an alternative to stainless steel. Manufacturer's
standard construction material is acceptable only in noncoastal and noncorrosive environments.
In last sentence use IEEE C57.12.28 for galvanized enclosures. Use IEEE C57.12.29
for stainless steel enclosures.
The [switchboard][switchgear] enclosure shall be a[ outdoor] NEMA ICS 6 Type [3R][1][__][as indicated][ fabricated
entirely of 12 gauge ASTM A 167 type 304 or 304L stainless steel]. Enclosure shall be bolted together with removable
bolt-on side and[ hinged] rear covers[, and sloping roof downward toward rear].[ Front[ and rear] doors shall
be provided with[ stainless steel] padlockable vault handles with a three point catch.] Bases, frames and channels
of enclosure shall be corrosion resistant and shall be fabricated of[ ASTM A 167 type 304 or 304L stainless steel][
or][ galvanized steel]. Base shall include any part of enclosure that is within 75 mm 3 inches of concrete pad.[
Galvanized steel shall be ASTM A 123/A 123M, ASTM A 653/A 653M G90 coating, and ASTM A 153/A 153M, as applicable.
Galvanize after fabrication where practicable.] Paint enclosure, including bases, ASTM D 1535 light gray No.
61 or No. 49. Paint coating system shall comply with[ IEEE C57.12.28 for galvanized steel][ and][ IEEE C57.12.29
for stainless steel].
2.2.2.2 Bus Bars
NOTE: Use copper with silver-plated contact surfaces in exterior or damp locations
or for heavy motor loads.
Only choose the bracketed option requiring epoxy coating on the bus bars for
outdoor locations with a high concentration of airborne contaminants. Choose
this option primarily for outdoor waterfront or dirty industrial applications.
Bus bars shall be[ copper with silver-plated contact surfaces][ or][ aluminum with tin-plated contact surfaces].
Plating shall be a minimum of 0.005 mm (0.0002 inch) 0.0002 inch thick. Make bus connections and joints with
hardened steel bolts. The through-bus shall be rated at the full ampacity of the main throughout the switchboard.
Provide minimum 6.35 mm by 50.8 mm (one-quarter by 2 inch) one-quarter by 2 inch copper ground bus secured to
each vertical section along the entire length of the [switchboard][switchgear]. The neutral bus shall be rated
[100][_____] percent of the main bus continuous current rating[ as indicated].[ Phase bus bars shall be insulated
with an epoxy finish coating powder providing a minimum breakdown voltage of 16,000 volts per ASTM D 149.]
2.2.2.3 Main Section
The main section shall consist of[ main lugs only][ an individually mounted[ drawout][ air power circuit breaker[
with current-limiting fuses]][ insulated-case circuit breaker][ molded-case circuit breaker][ bolted pressure
switch][ fusible switch]][ and utility transformer compartment].
2.2.2.4 Distribution Sections
The distribution section[s] shall consist of[ [individually mounted,][drawout,]][ air power circuit breakers[
with current-limiting fuses]][ insulated-case circuit breakers][ molded-case circuit breakers][ bolted pressure
switches][ fusible switches][ and utility transformer compartments] as indicated.
[2.2.2.5 Combination Sections
Combination sections shall consist of[ molded-case circuit breakers][ fusible switches] for the[ main and] branch
devices as indicated.
][2.2.2.6 Auxiliary Sections
Auxiliary sections shall consist of indicated[ instruments,][ metering equipment,][ control equipment,][ transformer,][
and][ current transformer compartments] as indicated.
][2.2.2.7 Handles
Handles for individually mounted devices shall be of the same design and method of external operation. Label
handles prominently to indicate device ampere rating, color coded for device type. Identify ON-OFF indication
by handle position and by prominent marking.
]2.2.3 Protective Device
NOTE: Switchboard should be placed where the ambient temperature is less than
40 deg. C. However, should the ambient temperature be expected to exceed 40
Deg. C, the designer shall call for special calibration for the circuit breakers.
Provide ground fault protection of equipment for solidly grounded wye electrical
services of more than 150 volts to ground for each service disconnect rated
1000 amperes or more in accordance with NFPA 70.
If 48 Vdc or 125 Vdc electrically operated circuit breakers are required, the
appropriate DC control power supply information must be added to the specification.
Reference information can be obtained fS.
Provide[ main and] branch protective devices as indicated.
[2.2.3.1 Power Circuit Breaker
IEEE C37.13. [120 Vac][ electrically][ manually] operated [stationary][drawout], [unfused][fused],[ steel frame,]
low-voltage power circuit breaker with a short-circuit current rating[ of [_____] rms amperes symmetrical][ as
indicated] at [_____] volts. Breaker frame size shall be[ as indicated][ [_____] amperes].[ Equip electrically
operated breakers with motor-charged, stored-energy closing mechanism to permit rapid and safe closing of the
breaker against fault currents within the short time rating of the breaker, independent of the operator's strength
or effort in closing the handle.]
][2.2.3.2 Insulated-Case Breaker
UL listed, 100 percent rated,[ stationary][ drawout],[ 120 Vac],[ electrically] [manually] operated, low voltage,
insulated-case circuit breaker, with a short-circuit current rating[ of [_____] rms symmetrical amperes][ as
indicated] at [_____] volts. Breaker frame size shall be[ [_____] amperes][ as indicated].[ Equip electrically
operated breaker with motor-charged, stored-energy closing mechanism to permit rapid and safe closing of the
breaker against fault currents within the short time rating of the breaker, independent of the operator's strength
or effort in closing the handle.]
][2.2.3.3 Molded-Case Circuit Breaker
UL 489. UL listed and labeled, 100 percent rated,[ stationary][ drawout],[ 120 Vac],[ electrically][ manually]
operated, low voltage molded-case circuit breaker, with a short-circuit current rating of[ [_____] rms symmetrical
amperes][ as indicated] at [_____] volts. Breaker frame size shall be[ [_____] amperes][ as indicated]. Series
rated circuit breakers are unacceptable.
][2.2.3.4 Fusible Switches
Fusible Switches: Quick-make, quick-break, hinged-door type.[ Switches serving as motor disconnects shall be
horsepower rated.] Fuses shall be current-limiting cartridge type conforming to[ UL 198M, Class J for 0 to 600
amperes and Class L for 601 to 6000 amperes][ UL 198M, Class [RK1][RK5] for 0 to 600 amperes].
Fuseholders: UL 512.
][2.2.3.5 Integral Combination Breaker and Current-Limiting Fuses
UL 489. Provide integral combination molded-case circuit breaker and current-limiting fuses[ as indicated][
rated [_____] amperes] with a minimum short-circuit-current rating equal to the short-circuit-current rating
of the [switchboard][switchgear] in which the circuit breaker will be mounted. Series rated circuit breakers
are unacceptable. Coordination of overcurrent devices of the circuit breaker and current-limiting fuses shall
be such that on overloads or fault currents of relatively low value, the overcurrent device of the breaker will
be operated to clear the fault. For high magnitude short circuits above a predetermined value[ crossover point],
the current-limiting fuses shall operate to clear the fault. Housing for the current-limiting fuses shall be
an individual molding readily removable from the front and located at the load side of the circuit breaker.
If the fuse housing is removed, a blown fuse shall be readily evident by means of a visible indicator. Removal
of fuse housing shall cause the breaker contacts to open, and it shall not be possible to close the breaker contacts
with the fuse housing removed. It shall not be possible to insert the fuse housing with a blown fuse or with
one fuse missing. The blowing of any of the fuses shall cause the circuit breaker contacts to open.
][2.2.4 Drawout Breakers
Equip drawout breakers with disconnecting contacts, wheels, and interlocks for drawout application. The main,
auxiliary, and control disconnecting contacts shall be silver-plated, multifinger, positive pressure, self-aligning
type. Each drawout breaker shall be provided with four-position operation. Each position shall be clearly identified
by an indicator on the circuit breaker front panel.
a. Connected Position: Primary and secondary contacts are fully engaged. Breaker must be tripped before
racking into or out of position.
b. Test Position: Primary contacts are disconnected but secondary contacts remain fully engaged. Position
shall allow complete test and operation of the breaker without energizing the primary circuit.
c. Disconnected Position: Primary and secondary contacts are disconnected.
d. Withdrawn (Removed) Position: Places breaker completely out of compartment, ready for removal.
Removal of the breaker shall actuate assembly that isolates the primary stabs.
][2.2.5 Electronic Trip Units
Equip[ main and][ distribution] breakers[ as indicated] with a solid-state tripping system consisting of three
current sensors and a microprocessor-based trip unit that will provide true rms sensing adjustable time-current
circuit protection. The ampere rating of the current sensors shall be[ as indicated][ [_____] amperes][ the
same as the breaker frame rating]. The trip unit ampere rating shall be[ as indicated][ [_____] amperes].[
Ground fault protection shall be[ as indicated][ zero sequence sensing][ residual type sensing].][ The electronic
trip units shall have the following features[ as indicated].]
NOTE: In the items below, choose the bracketed item "main" when the item only
applies to the main breaker.
Provide ground fault protection of equipment for solidly grounded wye electrical
services of more than 150 volts to ground for each service disconnect rated
1000 amperes or more in accordance with NFPA 70.
[a. [Indicated ]Breakers shall have long delay pick-up and time settings, and LED indication of cause
of circuit breaker trip.]
[b. Main breakers shall have[ short delay pick-up and time settings][ and][, instantaneous settings][
and][ ground fault settings][ as indicated].]
[c. Distribution breakers shall have[ short delay pick-up and time settings][, instantaneous settings][,
and ground fault settings][ as indicated].]
[d. [Main ]Breakers shall have a digital display for phase and ground current.]
[e. [Main ]Breakers shall have a digital display for watts, vars, VA, kWh, kvarh, and kVAh.]
[f. [Main ]Breakers shall have a digital display for phase voltage, and percent THD voltage and current.]
[g. [Main ]Breakers shall have provisions for communication via a network twisted pair cable for remote
monitoring and control.]
][2.2.6 Electronic Trip Unit Central Monitor
Provide a microprocessor-based device designed to monitor and display parameters of the circuit breaker electronic
trip units. The central monitor shall have the following features:
a. Alphanumeric display.
b. Indication of circuit breaker status; tripped, open, closed.
c. Cause of circuit breaker trip.
d. Phase, neutral, and ground current for each breaker.
e. Energy parameters for each breaker.
f. Provisions for communicating directly to a remote computer.
][2.2.7 Instruments
ANSI C39.1 for electrical indicating switchboard instruments, with 2 percent accuracy. The ac ammeters and voltmeters
shall be a minimum of 50.8 mm square (2 inches square) 2 inches square, with 4.36 rad (250-degree) 250-degree
scale. Provide single phase indicating instruments with flush-mounted transfer switches for reading three phases.
[2.2.7.1 Ac Ammeters
[Self-contained, ][Transformer rated, 5-ampere input, for use with a [_____] to 5-ampere current transformer
ratio, ]0 to [_____]-ampere scale range, 60 hertz.
][2.2.7.2 Ac Voltmeters
Self-contained.
][2.2.7.3 Instrument Control Switches
Provide rotary cam-operated type with positive means of indicating contact positions. Switches shall have silver-to-silver
contacts enclosed in a protective cover which can be removed to inspect the contacts.
]][2.2.8 Watthour and Digital Meters
NOTE: When Section 23 09 54.00 20 DIRECT DIGITAL CONTROL SYSTEMS or Section
23 09 23 DIRECT DIGITAL CONTROL FOR HVAC AND OTHER LOCAL BUILDING SYSTEMS is
used, coordinate meter requirements. Form 9S, in text below, is for three-phase,
four-wire wye systems, for other system configurations, designer shall determine
the appropriate form designation.
[2.2.8.1 Digital Meters
NOTE: Digital metering incorporates the latest technology and provides additional
information, often without additional cost. A control power transformer (115
V or 130 V) is normally required with this type of metering.
IEEE C37.90.1 for surge withstand. Provide true rms, plus/minus one percent accuracy, programmable, microprocessor-based
meter enclosed in sealed cases with a simultaneous three line, twelve value LED display. Meters shall have 16
mm (0.56 inch) 0.56 inch, minimum, LEDs.[ Watthour meter shall have 16 mm (0.56 inch) 0.56 inch, minimum, LEDs.]
The meters shall accept[ input from standard 5A secondary instrument transformers][ and][ direct voltage monitoring
range to [300][600] volts, phase to phase]. Programming shall be via a front panel display and a communication
interface with a computer. Password secured programming shall be stored in non-volatile EEPROM memory. Digital
communications shall be Modbus [ASCII][RTU] protocol via a [RS232C][RS485] serial port[ and an independently
addressable [RS232C][RS485] serial port]. The meter shall calculate and store average max/min demand values
for all readings based on a user selectable sliding window averaging period. The meter shall have programmable
hi/low set limits with two Form C dry contact relays when exceeding alarm conditions.[ Meter shall provide Total
Harmonic Distortion (THD) measurement to the thirty-first order.][ Historical trend logging capability shall
include ability to store up to 100,000 data points with intervals of 1 second to 180 minutes. The unit shall
also store and time stamp up to 100 programmable triggered conditions.][ Event waveform recording shall be triggered
by the rms of 2 cycles of voltage or current exceeding programmable set points. Waveforms shall be stored for
all 6 channels of voltage and current for a minimum of 10 cycles prior to the event and 50 cycles past the event.]
[a. Multi-Function Meter: Meter shall simultaneously display a selected phase to neutral voltage, phase
to phase voltage, percent phase to neutral voltage THD, percent phase to phase voltage THD; a selected
phase current, neutral current, percent phase current THD, percent neutral current; selected total PF,
kW, KVA, kVAR, FREQ, kVAh, kWh. Detected alarm conditions include over/under current, over/under voltage,
over/under KVA, over/under frequency, over/under selected PF/kVAR, voltage phase reversal, voltage imbalance,
reverse power, over percent THD. The meter shall have a Form C KYZ pulse output relay.]
[b. Power Meter: Meter shall simultaneously display Watts, VARs, and selected KVA/PF. Detected alarm
conditions include over/under KVA, over/under PF, over/under VARs, over/under reverse power.]
[c. Volt Meter: Meter shall be selectable between simultaneous display of the three phases of phase
to neutral voltages and simultaneous display of the three phases of the phase to phase voltages. Detected
alarm conditions include over/under voltage, over/under voltage imbalance, over percent THD.]
[d. Ammeter: Meter shall simultaneously display phase A, B, and C currents. Detected alarm conditions
include over/under current, over percent THD.]
[e. Digital Watthour Meter: Meter shall have a single selectable display for watts, total kilowatt
hours (kWh) and watt demand (Wd). The meter shall have a Form C KYZ pulse output relay.]
][2.2.8.2 Electronic Watthour Meter
Provide a switchboard style electronic programmable watthour meter, semi-drawout, semi-flush mounted, as indicated.
Meter shall either be programmed at the factory or shall be programmed in the field. When field programming
is performed, turn field programming device over to the Contracting Officer at completion of project. Meter
shall be coordinated to system requirements and conform to IEEE C12.16.
a. Design: Provide meter designed for use on a 3-phase, 4-wire, [208Y/120][480Y/277] volt system with
3 current transformers. Include necessary KYZ pulse initiation hardware for Energy Monitoring and Control
System (EMCS)[ as specified in[ Section 23 09 23 DIRECT DIGITAL CONTROL FOR HVAC AND OTHER LOCAL BUILDING
SYSTEMS]].
b. Coordination: Provide meter coordinated with ratios of current transformers and transformer secondary
voltage.
c. Class: 20. Form: [9S][___]. Accuracy: +/- 1.0 percent. Finish: Class II.
d. Kilowatt-hour Register: 5 digit electronic programmable type.
e. Demand Register:
1. Provide solid state ANSI C12.15.
2. Meter reading multiplier: Indicate multiplier on the meter face.
3. Demand interval length: shall be programmed for [15][30][60] minutes with rolling demand
up to six subintervals per interval.
f. Meter fusing: Provide a fuse block mounted in the metering compartment containing one fuse per phase
to protect the voltage input to the watthour meter. Size fuses as recommended by the meter manufacturer.
][2.2.8.3 Electro-Mechanical Watthour Meters
NOTE: On standard projects, use of the electronic meter versus the optional
electromechanical meter is recommended due to decreasing availability of electromechanical
meters.
NEMA C12.10. Kilowatt-hour meters shall be[ two][ three][ four]-stator, transformer rated, polyphase, 60 hertz,[
surface][ semiflush] mounted,[ drawout][ semidrawout] switchboard meters[ 120 volt for use on a four-wire wye,
three phase, 208Y/120 volt system][ 240 volt for use on a four-wire wye, three-phase 480Y/277 volt system].
Meter shall have a five-dial pointer type register.[ The kilowatt-hour meter shall have a[ sweep-hand][ cumulative]
type kilowatt demand register with [15][30][60]-minute interval conforming to NEMA C12.4.] Provide correct multiplier
on face of meter.
]]2.2.9 Current Transformers
NOTE: Select the appropriate current transformer (CT) ratio, continuous-thermal-current
rating factor (RF) at 30 degrees C and ANSI Metering Accuracy Class values based
on the CT Ratio which is just below the rating of the main protective device.
Select an ANSI Metering Accuracy Class in accordance with the following table:
CT Ratio RF Accuracy Class
200/5 4.0 0.3 thru B-0.1
300/5 3.0 0.3 thru B-0.2
400/5 4.0 0.3 thru B-0.2
600/5 3.0 0.3 thru B-0.5
800/5 2.0 0.3 thru B-0.5
1200/5 1.5 0.3 thru B-0.5
1500/5 1.5 0.3 thru B-0.9
2000/5 1.5 0.3 thru B-1.8
IEEE C57.13. Transformers shall be single ratio, 60 hertz, [_____] to 5-ampere ratio, [_____] rating factor,
with a metering accuracy class of 0.3 through [_____].
[2.2.10 Transformer
NOTE: Coordinate with Section 26 20 00 INTERIOR DISTRIBUTION SYSTEM, when transformer
section is provided. Use UL 891 for switchboards and UL 1558 for switchgear.
Provide transformer section in [switchboard][switchgear] in accordance with [UL 891][UL 1558] and as indicated.
The transformer and section shall be suitable for the installation.[ Transformers greater than 10 kVA shall
be tested in accordance with UL 891.] Transformer shall conform to the requirements of Section 26 20 00 INTERIOR
DISTRIBUTION SYSTEM.
][2.2.11 Meter Fusing
Provide a fuse block mounted in the metering compartment containing one fuse per phase to protect the voltage
input to voltage sensing meters. Size fuses as recommended by the meter manufacturer.
][2.2.12 Heaters
Provide 120-volt heaters in each [switchboard][switchgear] section. Heaters shall be of sufficient capacity
to control moisture condensation in the section, shall be 250 watts minimum, and shall be controlled by a thermostat[
and humidistat] located in the section. Thermostat shall be industrial type, high limit, to maintain sections
within the range of 15 to 32 degrees C (60 to 90 degrees F) 60 to 90 degrees F.[ Humidistat shall have a range
of 30 to 60 percent relative humidity.] Supply voltage for the heaters shall be obtained from a control power
transformer within the [switchboard][switchgear]. If heater voltage is different than switchboard voltage, provide
transformer rated to carry 125 percent of heater full load rating. Transformer shall have 220 degrees C insulation
system with a temperature rise not exceeding 115 degrees C and shall conform to NEMA ST 20.[ Energize electric
heaters in switchboard assemblies while the equipment is in storage or in place prior to being placed in service.
Provide method for easy connection of heater to external power source. Provide temporary, reliable external
power source if commercial power at rated voltage is not available on site.]
]2.2.13 Terminal Boards
Provide with engraved plastic terminal strips and screw type terminals for external wiring between components
and for internal wiring between removable assemblies. Terminal boards associated with current transformers shall
be short-circuiting type. Terminate conductors for current transformers with ring-tongue lugs. Terminal board
identification shall be identical in similar units. External wiring shall be color coded consistently for similar
terminal boards.
2.2.14 Wire Marking
Mark control and metering conductors at each end. Provide factory-installed, white, plastic tubing, heat stamped
with black block type letters on factory-installed wiring. On field-installed wiring, provide white, preprinted,
polyvinyl chloride (PVC) sleeves, heat stamped with black block type letters. Each sleeve shall contain a single
letter or number, shall be elliptically shaped to securely grip the wire, and shall be keyed in such a manner
to ensure alignment with adjacent sleeves. Provide specific wire markings using the appropriate combination
of individual sleeves. Each wire marker shall indicate the device or equipment, including specific terminal
number to which the remote end of the wire is attached.
2.3 MANUFACTURER'S NAMEPLATE
Each item of equipment shall have a nameplate bearing the manufacturer's name, address, model number, and serial
number securely affixed in a conspicuous place; the nameplate of the distributing agent will not be acceptable.
This nameplate and method of attachment may be the manufacturer's standard if it contains the required information.
2.4 FIELD FABRICATED NAMEPLATES
NOTE: Use the bracketed sentence to specify labels for switchboards or switchgear
where emergency breakers are located within the switchboards or switchgear.
Provide note on the drawings to indicate where red labels are required.
ASTM D 709. Provide laminated plastic nameplates for each[ switchboard,][ switchgear,] equipment enclosure,
relay, switch, and device; as specified in this section or as indicated on the drawings. Each nameplate inscription
shall identify the function and, when applicable, the position. Nameplates shall be melamine plastic, 3 mm 0.125
inch thick, white with [black][_____] center core.[ Provide red laminated plastic label with white center core
where indicated.] Surface shall be matte finish. Corners shall be square. Accurately align lettering and engrave
into the core. Minimum size of nameplates shall be 25 by 65 mm one by 2.5 inches. Lettering shall be a minimum
of 6.35 mm 0.25 inch high normal block style.
2.5 SOURCE QUALITY CONTROL
2.5.1 Equipment Test Schedule
The Government reserves the right to witness tests. Provide equipment test schedules for tests to be performed
at the manufacturer's test facility. Submit required test schedule and location, and notify the Contracting
Officer 30 calendar days before scheduled test date. Notify Contracting Officer 15 calendar days in advance
of changes to scheduled date.
a. Test Instrument Calibration
1. The manufacturer shall have a calibration program which assures that all applicable test
instruments are maintained within rated accuracy.
2. The accuracy shall be directly traceable to the National Institute of Standards and Technology.
3. Instrument calibration frequency schedule shall not exceed 12 months for both test floor
instruments and leased specialty equipment.
4. Dated calibration labels shall be visible on all test equipment.
5. Calibrating standard shall be of higher accuracy than that of the instrument tested.
6. Keep up-to-date records that indicate dates and test results of instruments calibrated or
tested. For instruments calibrated by the manufacturer on a routine basis, in lieu of third
party calibration, include the following:
(a) Maintain up-to-date instrument calibration instructions and procedures for each test instrument.
(b) Identify the third party/laboratory calibrated instrument to verify that calibrating standard
is met.
2.5.2 [Switchboard][Switchgear] Design Tests
NOTE: Use the first bracketed option for switchboards and the second bracketed
option for switchgear.
[NEMA PB 2 and UL 891][IEEE C37.20.1 and UL 1558].
2.5.2.1 Design Tests
Furnish documentation showing the results of design tests on a product of the same series and rating as that
provided by this specification.
a. Short-circuit current test
b. Enclosure tests
c. Dielectric test
[2.5.2.2 Additional design tests
NOTE: Include additional design tests when the switchboard or switchgear main
bus is rated greater than 4000 amperes.
In addition to normal design tests, perform the following tests on the actual equipment. Furnish reports which
include results of design tests performed on the actual equipment.
a. Temperature rise tests
b. Continuous current
]2.5.3 [Switchboard][Switchgear] Production Tests
NOTE: Use the first bracketed option for switchboards and the second bracketed
option for switchgear.
[NEMA PB 2 and UL 891][IEEE C37.20.1 and UL 1558]. Furnish reports which include results of production tests
performed on the actual equipment for this project. These tests include:
a. 60-hertz dielectric tests
b. Mechanical operation tests
c. Electrical operation and control wiring tests
d. Ground fault sensing equipment test
[2.6 COORDINATED POWER SYSTEM PROTECTION
NOTE: Use this paragraph only for Army projects.
The requirement for studies in this section depends on the complexity and extent
of the power system. Delete this requirement for projects of limited scope,
projects having protective devices which are not adjustable or for which coordination
is not possible (standard molded case circuit breakers); projects involving
simple extension of 600 volt level service to a building or facility from an
existing transformer (750 kVA or less); or projects involving simple extension
of 600 volt level service to a building or facility from a new transformer (750
kVA or less).
Provide a power system study as specified in Section 26 28 01.00 10 COORDINATED POWER SYSTEM PROTECTION.
]PART 3 EXECUTION
3.1 INSTALLATION
Electrical installations shall conform to IEEE C2, NFPA 70, and to the requirements specified herein.
3.2 GROUNDING
NOTE: Where rock or other soil conditions prevent obtaining a specified ground
value, specify other methods of grounding. Where it is impractical to obtain
the indicated ground resistance values, make every effort to obtain ground resistance
values as near as possible to the indicated values.
NFPA 70 and IEEE C2, except that grounds and grounding systems shall have a resistance to solid earth ground
not exceeding 5 ohms.
3.2.1 Grounding Electrodes
Provide driven ground rods as specified in[ Section 33 71 02.00 20 UNDERGROUND UNDERGROUND TRANSMISSION AND DISTRIBUTION][
Section 33 70 02.00 10 UNDERGROUND TRANSMISSION AND DISTRIBUTION SYSTEM, UNDERGROUND]. Connect ground conductors
to the upper end of the ground rods by exothermic weld or compression connector. Provide compression connectors
at equipment end of ground conductors.
3.2.2 Equipment Grounding
Provide bare copper cable not smaller than No. 4/0 AWG not less than 610 mm 24 inches below grade connecting
to the indicated ground rods. When work in addition to that indicated or specified is directed to obtain the
specified ground resistance, the provision of the contract covering "Changes" shall apply.
3.2.3 Connections
Make joints in grounding conductors and loops by exothermic weld or compression connector. Exothermic welds
and compression connectors shall be installed as specified in[ Section 33 71 02.00 20 UNDERGROUND UNDERGROUND
TRANSMISSION AND DISTRIBUTION, paragraph entitled "Grounding Connections."][ Section 33 70 02.00 10 UNDERGROUND
TRANSMISSION AND DISTRIBUTION SYSTEM, UNDERGROUND.]
3.2.4 Grounding and Bonding Equipment
UL 467, except as indicated or specified otherwise.
3.3 INSTALLATION OF EQUIPMENT AND ASSEMBLIES
Install and connect equipment furnished under this section as indicated on project drawings, the approved shop
drawings, and as specified herein.
[3.3.1 Switchboard
NEMA PB 2.1.
][3.3.2 Switchgear
IEEE C37.20.1.
][3.3.3 Meters and Instrument Transformers
NEMA C12.1.
]3.3.4 Field Applied Painting
Where field painting of enclosures is required to correct damage to the manufacturer's factory applied coatings,
provide manufacturer's recommended coatings and apply in accordance with manufacturer's instructions.
3.3.5 Galvanizing Repair
Repair damage to galvanized coatings using ASTM A 780, zinc rich paint, for galvanizing damaged by handling,
transporting, cutting, welding, or bolting. Do not heat surfaces that repair paint has been applied to.
3.3.6 Field Fabricated Nameplate Mounting
Provide number, location, and letter designation of nameplates as indicated. Fasten nameplates to the device
with a minimum of two sheet-metal screws or two rivets.
3.4 FOUNDATION FOR EQUIPMENT AND ASSEMBLIES
NOTE: Mounting slab connections may have to be given in detail depending on
the requirements for the seismic zone in which the equipment is located. Include
construction requirements for concrete slab only if slab is not detailed in
drawings.
3.4.1 Exterior Location
Mount [switchboard][switchgear] on concrete slab. Unless otherwise indicated, the slab shall be at least 200
mm 8 inches thick, reinforced with a 150 by 150 mm (6 by 6 inch) 6 by 6 inch No. 6 mesh placed uniformly 100
mm 4 inches from the top of the slab. Slab shall be placed on a 150 mm 6 inch thick, well-compacted gravel base.
The top of the concrete slab shall be approximately 100 mm 4 inches above the finished grade. Edges above grade
shall have 15 mm 1/2 inch chamfer. The slab shall be of adequate size to project at least 200 mm 8 inches beyond
the equipment. Provide conduit turnups and cable entrance space required by the equipment to be mounted. Seal
voids around conduit openings in slab with water- and oil-resistant caulking or sealant. Cut off and bush conduits
75 mm 3 inches above slab surface. Concrete work shall be as specified in[ Section 03 30 00 CAST-IN-PLACE CONCRETE][
Section 03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE].
3.4.2 Interior Location
Mount [switchboard][switchgear] on concrete slab. Unless otherwise indicated, the slab shall be at least 100
mm 4 inches thick. The top of the concrete slab shall be approximately 100 mm 4 inches above finished floor.
Edges above floor shall have 15 mm 1/2 inch chamfer. The slab shall be of adequate size to project at least
100 mm 8 inches beyond the equipment. Provide conduit turnups and cable entrance space required by the equipment
to be mounted. Seal voids around conduit openings in slab with water- and oil-resistant caulking or sealant.
Cut off and bush conduits 75 mm 3 inches above slab surface. Concrete work shall be as specified in[ Section
03 30 00 CAST-IN-PLACE CONCRETE][ Section 03 31 00.00 10 CAST-IN-PLACE STRUCTURAL CONCRETE].
3.5 FIELD QUALITY CONTROL
Contractor shall submit request for settings of breakers to the Contracting Officer after approval of [switchboard][switchgear]
and at least 30 days in advance of their requirement.
3.5.1 Performance of Acceptance Checks and Tests
Perform in accordance with the manufacturer's recommendations and include the following visual and mechanical
inspections and electrical tests, performed in accordance with NETA ATS.
[3.5.1.1 Switchboard Assemblies
a. Visual and Mechanical Inspection
1. Compare equipment nameplate data with specifications and approved shop drawings.
2. Inspect physical, electrical, and mechanical condition.
3. Confirm correct application of manufacturer's recommended lubricants.
4. Verify appropriate anchorage, required area clearances, and correct alignment.
5. Inspect all doors, panels, and sections for paint, dents, scratches, fit, and missing hardware.
6. Verify that[ fuse and] circuit breaker sizes and types correspond to approved shop drawings.
[7. Verify that current transformer ratios correspond to approved shop drawings.]
8. Inspect all bolted electrical connections for high resistance using low-resistance ohmmeter,
verifying tightness of accessible bolted electrical connections by calibrated torque-wrench
method, or performing thermographic survey.
9. Confirm correct operation and sequencing of electrical and mechanical interlock systems.
10. Clean switchboard.
11. Inspect insulators for evidence of physical damage or contaminated surfaces.
12. Verify correct barrier[ and shutter] installation[ and operation].
13. Exercise all active components.
14. Inspect all mechanical indicating devices for correct operation.
15. Verify that vents are clear.
16. Test operation, alignment, and penetration of instrument transformer withdrawal disconnects.
17. Inspect control power transformers.
b. Electrical Tests
1. Perform insulation-resistance tests on each bus section.
2. Perform overpotential tests.
3. Perform insulation-resistance test on control wiring; Do not perform this test on wiring
connected to solid-state components.
4. Perform control wiring performance test.
5. Perform primary current injection tests on the entire current circuit in each section of
assembly.
[6. Perform phasing check on double-ended switchboard to ensure correct bus phasing from each
source.]
[7. Verify operation of switchboard heaters.]
][3.5.1.2 Switchgear
a. Visual and Mechanical Inspection
1. Compare equipment nameplate data with specifications and approved shop drawings.
2. Inspect physical, electrical, and mechanical condition.
3. Confirm correct application of manufacturer's recommended lubricants.
4. Verify appropriate anchorage, required area clearances, and correct alignment.
5. Inspect all doors, panels, and sections for paint, dents, scratches, fit, and missing hardware.
6. Verify that[ fuse and] circuit breaker sizes and types correspond to approved shop drawings.
[7. Verify that current transformer ratios correspond to approved shop drawings.]
8. Inspect all bolted electrical connections for high resistance using low-resistance ohmmeter,
verifying tightness of accessible bolted electrical connections by calibrated torque-wrench
method, or performing thermographic survey.
9. Confirm correct operation and sequencing of electrical and mechanical interlock systems.
10. Clean switchgear.
11. Inspect insulators for evidence of physical damage or contaminated surfaces.
12. Verify correct barrier[ and shutter] installation[ and operation].
13. Exercise all active components.
14. Inspect all mechanical indicating devices for correct operation.
15. Verify that vents are clear.
16. Test operation, alignment, and penetration of instrument transformer withdrawal disconnects.
17. Inspect control power transformers.
b. Electrical Tests
1. Perform insulation-resistance tests on each bus section.
2. Perform overpotential tests.
3. Perform insulation-resistance test on control wiring; Do not perform this test on wiring
connected to solid-state components.
4. Perform control wiring performance test.
5. Perform primary current injection tests on the entire current circuit in each section of
assembly.
[6. Perform phasing check on double-ended switchgear to ensure correct bus phasing from each
source.]
[7. Verify operation of switchgear heaters.]
]3.5.1.3 Circuit Breakers - Low Voltage - Power
a. Visual and Mechanical Inspection
1. Compare nameplate data with specifications and approved shop drawings.
2. Inspect physical and mechanical condition.
3. Confirm correct application of manufacturer's recommended lubricants.
4. Inspect anchorage, alignment, and grounding. Inspect arc chutes. Inspect moving and stationary
contacts for condition, wear, and alignment.
5. Verify that all maintenance devices are available for servicing and operating the breaker.
6. Verify that primary and secondary contact wipe and other dimensions vital to satisfactory
operation of the breaker are correct.
7. Perform all mechanical operator and contact alignment tests on both the breaker and its
operating mechanism.
8. Inspect all bolted electrical connections for high resistance using low-resistance ohmmeter,
verifying tightness of accessible bolted electrical connections by calibrated torque-wrench
method, or performing thermographic survey.
9. Verify cell fit and element alignment.
10. Verify racking mechanism.
b. Electrical Tests
1. Perform contact-resistance tests on each breaker.
2. Perform insulation-resistance tests.
3. Adjust Breaker(s) for final settings in accordance with Government provided settings.
4. Determine long-time minimum pickup current by primary current injection.
5. Determine long-time delay by primary current injection.
NOTE: Coordinate each option with each breaker type.
[6. Determine short-time pickup and delay by primary current injection.]
[7. Determine ground-fault pickup and delay by primary current injection.]
[8. Determine instantaneous pickup value by primary current injection.]
[9. Activate auxiliary protective devices, such as ground-fault or undervoltage relays, to
ensure operation of shunt trip devices; Check the operation of electrically-operated breakers
in their cubicle.]
10. Verify correct operation of any auxiliary features such as trip and pickup indicators, zone
interlocking, electrical close and trip operation, trip-free, and antipump function.
11. Verify operation of charging mechanism.
3.5.1.4 Circuit Breakers
[Low Voltage - Insulated-Case][ and ][Low Voltage Molded Case with Solid State Trips]
a. Visual and Mechanical Inspection
1. Compare nameplate data with specifications and approved shop drawings.
2. Inspect circuit breaker for correct mounting.
3. Operate circuit breaker to ensure smooth operation.
4. Inspect case for cracks or other defects.
5. Inspect all bolted electrical connections for high resistance using low resistance ohmmeter,
verifying tightness of accessible bolted connections and/or cable connections by calibrated
torque-wrench method, or performing thermographic survey.
6. Inspect mechanism contacts and arc chutes in unsealed units.
b. Electrical Tests
1. Perform contact-resistance tests.
2. Perform insulation-resistance tests.
3. Perform Breaker adjustments for final settings in accordance with Government provided settings.
4. Perform long-time delay time-current characteristic tests
NOTE: Coordinate each option with each breaker type.
[5. Determine short-time pickup and delay by primary current injection.]
[6. Determine ground-fault pickup and time delay by primary current injection.]
[7. Determine instantaneous pickup current by primary injection.]
[8. Verify correct operation of any auxiliary features such as trip and pickup indicators,
zone interlocking, electrical close and trip operation, trip-free, and anti-pump function.]
3.5.1.5 Current Transformers
a. Visual and Mechanical Inspection
1. Compare equipment nameplate data with specifications and approved shop drawings.
2. Inspect physical and mechanical condition.
3. Verify correct connection.
4. Verify that adequate clearances exist between primary and secondary circuit.
5. Inspect all bolted electrical connections for high resistance using low-resistance ohmmeter,
verifying tightness of accessible bolted electrical connections by calibrated torque-wrench
method, or performing thermographic survey.
6. Verify that all required grounding and shorting connections provide good contact.
b. Electrical Tests
1. Perform resistance measurements through all bolted connections with low-resistance ohmmeter,
if applicable.
2. Perform insulation-resistance tests.
3. Perform polarity tests.
4. Perform ratio-verification tests.
3.5.1.6 Metering and Instrumentation
a. Visual and Mechanical Inspection
1. Compare equipment nameplate data with specifications and approved shop drawings.
2. Inspect physical and mechanical condition.
3. Verify tightness of electrical connections.
b. Electrical Tests
1. Determine accuracy of meters at 25, 50, 75, and 100 percent of full scale.
2. Calibrate watthour meters according to manufacturer's published data.
3. Verify all instrument multipliers.
4. Electrically confirm that current transformer and voltage transformer secondary circuits
are intact.
3.5.1.7 Grounding System
a. Visual and Mechanical Inspection
1. Inspect ground system for compliance with contract plans and specifications.
b. Electrical Tests
1. IEEE Std 81. Perform ground-impedance measurements utilizing the fall-of-potential method.
On systems consisting of interconnected ground rods, perform tests after interconnections are
complete. On systems consisting of a single ground rod perform tests before any wire is connected.
Take measurements in normally dry weather, not less than 48 hours after rainfall. Use a portable
ground testing megger in accordance with manufacturer's instructions to test each ground or
group of grounds. The instrument shall be equipped with a meter reading directly in ohms or
fractions thereof to indicate the ground value of the ground rod or grounding systems under
test.
2. Submit the measured ground resistance of each ground rod and grounding system, indicating
the location of the rod and grounding system. Include the test method and test setup (i.e.,
pin location) used to determine ground resistance and soil conditions at the time the measurements
were made.
3.5.2 Follow-Up Verification
Upon completion of acceptance checks, settings, and tests, the Contractor shall show by demonstration in service
that circuits and devices are in good operating condition and properly performing the intended function. Circuit
breakers shall be tripped by operation of each protective device. Test shall require each item to perform its
function not less than three times. As an exception to requirements stated elsewhere in the contract, the Contracting
Officer shall be given 5 working days advance notice of the dates and times for checks, settings, and tests.