J2i FAA-C-1217H Chg 2 Electrical.pdf

FAA-C-1217H Chg 2 September 15, 2023

U.S. Department of Transportation Federal Aviation Administration

U.S. Department of Transportation

Federal Aviation Administration

Construction Specification

ELECTRICAL WORK, PREMISES WIRING

SUPERSEDING

FAA-C-1217H Chg 1

January 5, 2021 ii

Foreword

1. This specification is approved for use by all departments of the Federal Aviation Administration (FAA).

2. This specification defines the minimum installation requirements for electrical wiring within FAA facilities, buildings or structures, in yards, parking lots, and FAA premises. National and international codes such as the National Electric Code (NEC) primarily address safety. In particular, Paragraph 90.1(B) of the NEC states, "This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard, but not necessarily efficient, convenient, or adequate for good service or future expansion of electrical use." It is the intent of this specification to ensure that installations are not only free from hazard, but are efficient and adequate for the FAA’s mission needs. This specification does not supersede national codes, but augments them.

3. For instances where the NEC provides acceptable options, this specification may prescribe certain of these options and proscribe others.

4. Specific FAA facilities, e.g., Air Route Traffic Control Centers (ARTCC), Metroplex Control Facilities (MCF), Terminal Radar Control (TRACON), etc., may have requirements that are more stringent than these minimum requirements.

5. Comments, suggestions, or questions on this document should be addressed to:

Federal Aviation Administration Power Services Group, Systems Engineering Team, AJW-222 800 Independence Avenue, SW Washington, DC 20591 iii

Table of Contents

1 Scope

1.1 Scope

2 Applicable Documents

2.1 General

2.2 Government Documents

2.2.1 Specifications, standards, and handbooks

2.2.1.1 Specifications

2.2.1.2 Standards

2.2.1.3 Orders

2.3 Non-Government publications

2.4 Order of precedence

3 Definitions

4 General Requirements

4.1 General

4.2 Grounding

4.3 Safe Work Practices

4.4 Power Systems Analyses

4.5 Lightning Protection, Grounding, Bonding, and Shielding

4.6 Harmonics Control

4.7 Quality Assurance Requirements

4.8 Tests

4.8.1 General

4.8.2 Insulation resistance

4.8.3 Ground-fault Performance Testing

4.8.4 Load balancing

4.9 Facility-Specific Requirements

5 Detailed Requirements

5.1 Electrical Surge Protection

5.2 Wiring methods

5.2.1 General

5.2.1.1 Conductor routing

5.2.1.2 Conductor separation

5.2.2 Neutral conductor

5.2.3 Raceway systems

5.2.3.1 General

5.2.3.2 Conduit

5.2.3.2.1 General

5.2.3.2.2 Rigid Metal Conduit

5.2.3.2.3 Intermediate Metal Conduit

5.2.3.2.4 Electrical Metallic Tubing

5.2.3.2.5 Rigid Aluminum conduit

5.2.3.2.6 Rigid Nonmetallic Conduit

iv

5.2.3.2.7 Flexible metal conduit, including liquid-tight

5.2.3.2.8 Flexible nonmetallic conduit

5.2.3.2.9 Surface raceways

5.2.3.3 Wireways

5.2.3.4 Cable rack systems

5.2.3.4.1 General

5.2.3.4.2 Dimensions

5.2.4 Raceway support systems

5.2.4.1 General

5.2.4.2 Telecommunication raceways

5.2.5 Conductors

5.2.5.1 Uninsulated conductors

5.2.5.2 Insulated conductors

5.2.5.2.1 Fixture wiring

5.2.5.2.2 Conductor identification

5.2.5.2.3 Color Coding for Ungrounded Conductors

5.2.5.3 Connectors and Splices

5.2.6 Metal-Clad Cable: Type MC

5.2.6.1 Type MC installed in cable tray

5.2.6.2 Type MC installed in other than cable tray

5.2.6.3 Fire pump wiring

5.3 Boxes

5.3.1 Applications

5.3.2 Supports

5.4 Wiring devices

5.4.1 Receptacles

5.4.1.1 Ground Fault Circuit-Interrupter receptacles

5.4.1.2 Multioutlet Assemblies

5.4.1.2.1 General

5.4.1.2.2 Associated hardware

5.4.1.3 Emergency light receptacles

5.4.2 Wall switches

5.4.3 Device plates

5.5 Service equipment

5.5.1 Power

5.5.1.1 Service conduits

5.5.1.1.1 Underground service

5.5.1.1.2 Aerial service

5.5.1.2 Service disconnecting means

5.5.2 Ground fault protection

5.6 Panelboards

5.6.1 General

5.6.2 Wiring gutters

5.6.3 Circuit breakers

5.6.3.1 Thermal magnetic

5.6.3.2 Solid state

v

5.6.3.3 Self-enclosed circuit breakers

5.6.3.3.1 General

5.6.3.3.2 Thermal magnetic

5.6.3.3.3 Solid state/microprocessor

5.6.4 Bus bars

5.6.4.1 Ground bus

5.7 Safety switches

5.8 Cabinets

5.9 Motors and controls

5.9.1 Motors

5.9.2 Motor controls

5.9.2.1 Reduced-voltage controllers

5.9.3 Motor disconnecting means

5.10 Dry-type transformers

5.10.1 General

5.10.2 Windings and taps

5.10.3 Insulation

5.10.4 Terminal compartments

5.10.5 Sound pressure levels and vibration isolation

5.10.6 Enclosures

5.10.7 Mounting

5.11 Equipment Identification

5.12 Fuses

5.13 Lamps and lighting fixtures

5.13.1 General

5.13.2 Fluorescent fixtures

5.13.2.1 Recessed lighting

5.13.2.2 Suspended fluorescent fixtures

5.13.3 Suspended incandescent fixtures

5.13.4 Emergency lights

5.13.5 Lamps

5.14 Signal and communications

5.14.1 Entrance conduits

5.14.2 Transient protection demarcation box for electronic landlines

5.14.3 Fiber optics

6 Notes

6.1 Intended use

6.2 Tailoring guidance

Appendix A Acronyms and Abbreviations

Appendix B Using Twist-on Wire Connectors

1 Scope

1.1 Scope

This specification defines the minimum installation requirements for electrical wiring within FAA facilities, buildings or structures, in yards, parking lots, and FAA premises. For outdoor underground wiring methods not contained in this document, refer to FAA-C-1391.

The requirements in this specification are based on performance and safety, and may exceed those of the NFPA 70™, National Electric Code® (NEC), which deals with safety only. Some National Airspace System (NAS) operations facilities have performance requirements that exceed commercial and general government requirements listed in this specification. These include Air Route Traffic Control Centers (ARTCC), Metroplex Control Facilities (MCF), Terminal Radar Control Facilities (TRACON), and large Air Traffic Control Towers (ATCT). Such extra requirements concern communication wiring grounding, shielding, and lightning protection requirements (refer to FAA-

STD-019).

Where the phrase "unless otherwise indicated" or similar wording appears, it refers exclusively to other documents that are specific parts of electrical construction project contracts.

Change Record

1. Originator Name and Address AJW-22, Power Services Group

2. [] Proposed 3. Code Identification 4. Document No. FAA-C-1217H Chg 2

Washington, DC [X ] Approved 5. Code Identification 6. DCN No.

7. System Designation 8. Related ECR/NCP No.

9. Contract No. 10. Contractual Activity N/A

11. Product Integration Plan 12. Effectivity

This notice informs recipients that the standard identified by the number (and revision letter) shown in block 4 has been changed. The pages changed by this DCN (being those furnished herewith) carry the same date as the DCN. The page numbers and dates listed below in the summary of changed pages, combined with non-listed pages of the original issue of the revision shown in block 4, constitute the current version of this specification.

13. DCN No. 14. Pages changed S* A/D* 15. Date H version, initial release. 7/2018

H version, Change 1 update 1/2021

H version, Change 2 update: (1) scope - distinguish gray areas between premises and non-premises wiring, (2) Section 4: clarify burial depths and cover requirements; add safe work practice (dust control), (3) Section 5: conductor separation - critical power;

minimum conduit size; conduit burial depth requirement; limited exception on the use of flexible nonmetallic conduits; fire pump wiring requirements; minimum branch circuit conductor requirement; insulated conductors update; receptacles update.

11/2022

2 Applicable Documents

2.1 General

The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification, or those recommended for additional information or as examples. Although every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed.

2.2 Government Documents

2.2.1 Specifications, standards, and handbooks.

Latest versions of the following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

2.2.1.1 Specifications

FAA-C-1391 Installation, Termination, Splicing, and Transient/Surge Protection of

Underground Electrical Distribution System Power Cables W C 596 General Specification for Electrical Power Connectors A A 59544 Cable and Wire, Electrical (Power, Fixed Installation) W C 375 Circuit Breakers, Molded Case; Branch Circuit and Service W P 115 Panel, Power Distribution A A 55810 Conduit, Metal, Flexible A A 59551 Wire, Electrical, (uninsulated)

2.2.1.2 Standards

FAA-STD-019 Lightning and Surge Protection, Grounding, Bonding and Shielding

Requirements for Facilities and Electronic Equipment 10 CFR 431 Energy Efficiency Program for Certain Commercial and Industrial Equipment

2.2.1.3 Orders

JO 6950.27 Power System Studies JO 3900.64 Air Traffic Organization Electrical Safety Program

2.3 Non-Government publications

The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract.

National Fire Protection Association (NFPA) publications NFPA 70 National Electrical Code (NEC) NFPA 101 Life Safety Code

Underwriters' Laboratories (UL) Inc. standards

UL 5 Standard for Surface Metal Raceways and Fittings UL 50 Enclosures for Electrical Equipment UL 486A-486B Wire Connectors UL 486C Splicing Wire Connectors UL 486E Standard for Equipment Wiring Terminals for Use with Aluminum and/or

Copper Conductors UL 514A Metallic Outlet Boxes UL 514B Conduit, Tubing, and Cable Fittings UL 651 Standard for Schedule 40, 80, Type EB and A Rigid PVC Conduit and

Fittings UL 797 Electrical Metallic Tubing - Steel UL 870 Wireways, Auxiliary Gutters, and Associated Fittings UL 924 Emergency Lighting and Power Equipment

Institute of Electrical and Electronics Engineers (IEEE) Inc. standards STD C57.12.80 Standard Terminology for Power and Distribution Transformers STD 141 Recommended Practice for Electric Power Distribution for Industrial Plants

National Electrical Manufacturers Association (NEMA) standards MG-1 Standard for Motors and Generators ST 20 Dry Type Transformers for General Applications WD 1 General Requirements for Wiring Devices

Steel Structures Painting Council standards SSPC-PS 10.01 Hot-Applied Coal Tar Enamel Painting System

Telecommunications Industry Association./Electronic Industries Alliance TIA/EIA 568-B Commercial Building Telecommunications Cabling Standard TIA/EIA 569-A Commercial Building Standard for Telecommunication Pathways and Spaces

2.4 Order of precedence

FAA-STD-019, Lightning and Surge Protection, Grounding, Bonding and Shielding Requirements for Facilities and Electronic Equipment, is the governing standard for the listed items, and takes precedence over this specification. In all other cases of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

3 Definitions Definitions are derived from the NFPA 70, National Electric Code, except as noted.

Bonding Conductor or Jumper: A reliable conductor to ensure the required electrical conductivity between metal parts required to be electrically connected.

Disconnecting Means: A device, or group of devices, or other means by which the conductors of a circuit can be disconnect from their source of supply.

Electrical Metallic Tubing: An unthreaded thinwall raceway of circular cross-section designed for the physical protection and routing of conductors and cables and for use as an equipment grounding conductor when installed using appropriate fittings. Within FAA practice, acceptable EMT is made of steel with protective coatings.

Equipment Grounding Conductor: The conductive path installed to connect normally non-current-carrying metal parts of equipment together and to the system grounded conductor or to the grounding electrode conductor, or both. For FAA purposes, the Equipment Grounding Conductor (EGC) is to be green-insulated, solid or stranded, copper wire.

Flexible Metal Conduit: A raceway of circular cross-section made of helically wound, formed, interlocked ferrous metal (steel) strip.

Ground-Fault Circuit Interrupter (GFCI): A device intended for the protection of personnel that functions to deenergize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device, presently 6 mA or higher. Class A devices do not trip when the current to ground is less than 4 mA.

Grounded Conductor: A system or circuit conductor that is intentionally grounded.

Grounding Conductor: A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode or electrodes.

Grounding Electrode Conductor: A conductor used to connect the system grounded conductor or the equipment to a grounding electrode or to a point on the grounding electrode system.

Intermediate Metal Conduit (IMC): A steel threadable raceway of circular cross-section designed for the physical protection and routing of conductors and cables and for use as an equipment grounding conductor when installed with its integral or associated coupling and appropriate fittings.

Interrupting Capacity: The highest current at rated voltage that the device can interrupt. (IEEE Std 100, “IEEE Standard Dictionary of Electrical and Electronic Terms.”) Multioutlet Assembly: A type of surface, flush, or freestanding raceway designed to hold conductors and receptacles, assembled in the field or at the factory.

Neutral Conductor: The conductor connected to the neutral point of a system that is intended to carry current under normal conditions.

Neutral Point: The common point on a wye-connection in a polyphase system; the midpoint of a single-phase, 3-wire system; the midpoint of a single-phase portion of a 3-phase delta system; or the midpoint of a 3-wire, direct-current system. At the neutral point of the system, the vectorial sum of the nominal voltages from all other phases within the system that use the neutral, with respect to the neutral point, is zero potential.

Panelboard. A single panel or group of panel units designed for assembly in the form of a single panel, including buses and automatic overcurrent devices, and equipped with or without switches for the control of light, heat, or power circuits, designed to be placed in a cabinet or cutout box placed in or against a wall, partition, or other support, and accessible only from the front.

Premises Wiring (System): Interior and exterior wiring, including power, lighting, control, and signal circuit wiring together with all their associated hardware, fittings, and wiring devices, both permanently and temporarily installed. This includes (a) wiring from the service point or power source to the outlets or (b) wiring from and including the power source to the outlets where there is no service point. Such wiring does not include wiring internal to appliances, luminaires, motors, controllers, motor control centers, and similar equipment. Power sources include, but are not limited to, interconnected or stand-alone batteries, solar photovoltaic systems, other distributed generation systems, or generators. Specific to FAA applications, premises wiring consists of installations within or on buildings or structures, in yards, parking lots, and other areas associated with FAA facilities.

Relocatable Power Tap (RPT): A UL-1363 listed device that is a factory assembled, multiple outlet unit with a cord and plug, and may also include fuses, circuit breakers, switches and/or lights. RPTs are intended to be directly connected to a permanently installed receptacle. RPTs are also referred to as Temporary Power Tap (TPT) and power strips.

Qualified Person: Also known as “qualified worker.” A qualified person is one who follows the safe electrical work practices of the latest version of FAA Order 3900.64 and the latest version of NFPA 70E. The following definitions apply as appropriate: (a) Designers, Installers, Inspectors: A person knowledgeable in the construction and operation of electric power generation, transmission, and/or distribution equipment, along with associated hazards. One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved) (NFPA 70-2020); (b) Employers, employees, and OSHA: One who has demonstrated skills and knowledge related to the construction and operation of electrical equipment and installations and has received safety training to identify the hazards and reduce the associated risk (NFPA 70E-2021).

Rigid Metal Conduit (RMC): A threadable raceway of circular cross-section designed for the physical protection and routing of conductors and cables and for use as an equipment grounding conductor when installed with its integral or associated coupling and appropriate fittings. RMC is generally made of steel (ferrous) with protective coatings or aluminum (nonferrous). Within FAA practice, acceptable RMC is galvanized (zinc-coated) steel.

Service: The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.

Service Point: The point of connection between the facilities of the serving utility and the premises wiring.

Switchboard. A large single panel, frame, or assembly of panels on which are mounted on the face, back, or both, switches, overcurrent and other protective devices, buses, and usually instruments.

Switchboards are generally accessible from the rear as well as from the front and are not intended to be installed in cabinets.

4 General Requirements

4.1 General

The orders, standards, rules, regulations, and reference specifications enumerated herein are considered minimum requirements. FAA installations shall meet or exceed the requirements of NFPA 70, National Electric Code (NEC). Where the NEC provides for multiple options, this specification may prescribe some options and proscribe others. Contractors shall furnish and install higher grades of materials and workmanship required by this specification in addition to adhering to other commercial standards.

Facility design and construction standards for specific NAS facilities may have detailed requirements for use of a particular wiring method. Subsection 4.9 includes some of these requirements. This specification for general electrical work at FAA facilities does not supersede any facility-specific standard. In no event shall electrical codes be violated.

Unscheduled interruptions of the electrical service to FAA facilities may cause aircraft accidents and loss of life. Work requiring a temporary or permanent energizing and/or deenergizing of equipment shall be scheduled in writing with the onsite FAA maintenance personnel. Only onsite FAA maintenance personnel are authorized to energize equipment, deenergize equipment, or operate a circuit breaker, switch, or fuse in an FAA facility. Work procedures shall include lock-out/tag-out procedures in accordance with FAA Order 3900.64 and NFPA 70E.

4.2 Grounding

All grounding shall be in accordance with FAA-STD-019, current revision, and the FAA-accepted version NEC, unless otherwise stated in Section 5, Detailed Requirements.

Each overcurrent device shall have its own equipment grounding conductor, i.e.: a single-pole single-phase overcurrent device shall be supplied with an equipment grounding conductor; a two-pole, single-phase overcurrent device shall be supplied with its own equipment grounding conductor; and a three-pole, three-phase overcurrent device shall be supplied with its own equipment grounding conductor. The equipment-grounding conductor shall be installed in the same conduit as its related branch and feeder conductors and shall be connected to the ground bus in the branch or distribution panelboard. Metal conduit housing the equipment grounding conductor shall be electrically continuous, forming a parallel path to the equipment grounding conductor, except as allowed by the NEC. Where parallel feeders are installed in more than one raceway, a full-sized equipment grounding conductor shall be installed in each raceway.

4.3 Safe Work Practices

All work performed under this document shall follow the safe electrical work practices of the latest version of FAA Order 3900.64 and the latest version of NFPA 70E.

Dusting off electrical equipment is highly recommended to minimize the effects of dust accumulation.

Hazards of dust accumulation include short circuits, ground faults, and the clogging of equipment ventilation channels.

4.4 Power Systems Analyses

The distribution system and all component parts, when installed or as modified, must include a load flow analysis, short circuit analysis, a protective device coordination analysis, and an arc flash risk assessment, in accordance with the current versions of (1) FAA Order 6950.27, (2) NFPA 70E, (3) IEEE 1584, and (4) other PSG guidance. Arc flash labels are installed as part of the arc flash study in accordance with FAA Order 3900.64, and current version of NFPA 70E.

4.5 Lightning Protection, Grounding, Bonding, and Shielding

FAA grounding requirements exceed those of the NEC. These requirements are considered the minimum necessary to adequately provide for the needs of the FAA missions – to prevent delay or loss of service, to minimize or preclude outages, and to enhance personnel safety. Further, the requirements in the document have been coordinated with industry standards, and in some cases exceed industry standards where necessary to meet the FAA missions. Refer to FAA-STD-019, Lightning and Surge Protection, Grounding, Bonding and Shielding Requirements for Facilities and Electronic Equipment, when installing all NAS equipment.

All surge protective devices shall be installed in accordance with the latest revision of FAA-STD-019.

4.6 Harmonics Control

The distribution system and all component parts, when installed or as modified, shall be in accordance with IEEE Standard 519, Recommended Practices and Requirements for Harmonic Control.

4.7 Quality Assurance Requirements

All design of new facilities and modifications to existing facilities shall be subject to the scrutiny of the Joint Acceptance Inspection (JAI).

4.8 Tests

4.8.1 General

Unless otherwise indicated, the contractor shall furnish all test instruments, materials, and labor necessary to perform the following tests. All tests shall be performed in the presence of the Contracting Officer’s designated representative. All instruments shall have been calibrated within a period of one year preceding testing. Calibrations shall be traceable to applicable industry recognized standards.

4.8.2 Insulation resistance

Cables, conductors, and wires shall be tested prior to energization. Intrafacility wiring/cabling may be tested with a standard ohmmeter set to the highest scale, measuring between phases, phase and neutral, phase and ground. A reading of infinite resistance indicates an acceptable installation. All testing shall be accomplished before connection is made to any existing equipment.

Intrafacility wiring/cabling, feeder, and branch circuit insulation tests shall be performed after installation, but before connection to fixtures or appliances. Motors shall be tested for grounds or short circuits after installation but before start-up. Testing should be performed using a 500-volt dc insulation resistance tester, but may be done with a standard ohmmeter set to the highest scale, measuring between phases, phase and neutral, phase and ground. Using the 500-volt DC meter method, a resistance of 30 megohms or greater indicates an acceptable installation. Using the standard ohmmeter method, a reading of infinite resistance indicates an acceptable installation. All conductors shall test free of short circuits and grounds.

4.8.3 Ground-fault Performance Testing

The ground-fault protection system shall be tested in accordance with the NEC and set as appropriate.

4.8.4 Load balancing

All polyphase electrical distribution systems shall be balanced to the greatest extent possible. Current readings with a true RMS ammeter will be taken for the purpose of load balancing. These readings shall be taken at the service entrance, each feeder panelboard, each branch panelboard, and each separately derived source. Single-phase loads must be redistributed where there is a greater than 20% difference between readings in any two phases.

4.9 Facility-Specific Requirements

For Air Route Traffic Control Centers (ARTCC), Metroplex Control Facilities (MCF), and Large Terminal Radar Approach Control Facilities (TRACON), zinc-coated ferrous rigid metal conduit (RMC) or intermediate metal conduit (IMC) shall be used for all distribution panel feeders, transformer feeders, motor control center feeders and distribution switchboards. Electrical metallic tubing (EMT) may be used for communication, lighting and branch circuits.

For underground burial depths and methods, the requirements of FAA-C-1391 shall apply when practical, with some exceptions at the premises, including:

• Under the concrete slab of a building/shelter,

• Where building footings are present,

• Where other utility, communications, control, or other services interfere with requirements,

• Under streets, roads, driveways, and parking lots.

When FAA-C-1391 cannot be followed, other permitted wiring methods are:

• Under the concrete slab of a building/shelter, use rigid metallic conduit with zero inches of cover required,

• Under a minimum 4 in. thick concrete exterior slab with no vehicular traffic, and the slab extending not less than 6 in. beyond the underground installation, use RMC with 4 in.

minimum cover,

• Under streets, highways, roads, alleys, driveways, and parking lots, use RMC conduit with 24

in. minimum cover,

• In a trench below 2 in. thick concrete or equivalent, use RMC with 6 in. minimum cover.

• In instances such as above a solid ledge or where conduit cannot penetrate the soil, FAA-designed and approved installation specifications and drawings are permitted provided they use galvanized rigid steel conduit or other ferrous shielding methods.

5 Detailed Requirements

5.1 Electrical Surge Protection

All electrical surge protective devices shall be installed in accordance with the latest revision of FAA- STD-019, Lightning and Surge Protection, Grounding, Bonding and Shielding Requirements for Facilities and Electronic Equipment.

5.2 Wiring methods

5.2.1 General

All wiring shall consist of insulated copper conductors installed in metallic raceways, unless otherwise specified.

5.2.1.1 Conductor routing

Panelboards, surge protective devices, disconnect switches, etc., shall not be used as raceways for conductor routing other than conductors that originate or terminate in these enclosures. Per the NEC, grounding conductors for isolated ground receptacles will be allowed to pass through these enclosures as required.

5.2.1.2 Conductor separation

Power conductors such as branch-circuit and feeder conductors shall be routed separately from all non-power (e.g., signal, communication, etc. conductor types. This may be accomplished by routing power conductors and other conductors in separate raceways. Rated partitions in a common raceway may be used with documented FAA engineering approval.

The output of a facility UPS provides conditioned and uninterruptible power to NAS operational equipment. The conditioned and uninterruptible circuit is NAS critical power. For any new construction, NAS critical power shall be separated from all other wiring and equipment.

5.2.2 Neutral conductor

Shared/common neutral conductors shall not be permitted, i.e., each overcurrent device shall have its own separate neutral conductor. Neutral conductor sizes shall not be less than the respective feeder or phase conductor sizes.

5.2.3 Raceway systems

5.2.3.1 General

Conduit interiors shall be visibly clean of debris, and swabbed if necessary, before conductors are installed. Ends of raceway systems not terminated in boxes or cabinets shall be capped. Exposed raceways shall be installed parallel to or at right angles with the lines of the structure, with exceptions as approved by the Contracting Officer’s Representative (COR). Crushed or deformed raceways shall not be installed. A pull wire shall be installed in all empty tubing and conduit systems in which wiring is to be installed by others. The pull wire shall be 14 AWG zinc-coated steel, or plastic having a minimum 200-pound tensile strength. A minimum of ten (10) inches of slack shall be left at each end of the pull wire. MULETAPE® of minimum 200-pound pull strength may also be used, with 36 inches left at each end of the wire pull. Sections of raceways that pass through to damp, concealed, or underground locations shall be of a type allowed for such locations by NEC, and shall extend a minimum of 12 inches beyond the damp, concealed, or underground area. Where raceway has to be cut in the field, it shall be cut square and burrs and sharp edges removed. Where conduits penetrate walls or floors separating the building interior from the exterior, they shall be sealed to prevent moisture and rodent entry and to deter air transfer. In addition, where conduits penetrate walls separating individually controlled temperature or humidity controlled areas, they shall be sealed to prevent air circulation. Sealing methods and sealants shall be in accordance with NEC. Where conduits penetrate fire- resistant-rated walls, partitions, floors, or ceilings, the conduit and openings shall be fire stopped using approved methods to maintain the fire resistance rating.

5.2.3.2 Conduit

5.2.3.2.1 General

Minimum conduit size for power distribution shall be ¾ inch unless otherwise specified. Conduit for telephone and signal systems shall be allowed to be ½ inch.

Equipment such as Heating, Ventilating, and Air-Conditioning (HVAC) Direct Digital Control (DDC) systems, fire alarm control panels, light fixtures, etc. are often furnished with ½-inch knock-outs.

Trade size ½-inch conduit will be permitted for final connection to this equipment. Reducing bushings shall be used as necessary.

Where threads have to be cut on a conduit, the threads shall have the same effective length and shall have the same thread dimensions and taper as specified for factory-cut threads on conduit. For building/campus system conduit, follow NEC Table 300.5 for minimum burial depths.

Building/campus systems typically are low voltage (< 600 V) systems, e.g., ARTCCs, TRACONs, NEMCs, garages and outbuildings, or multiple-building campus configurations. Typical burial depth for campus systems is 24 in., but when conditions require, conduit shall at least meet the depths specified in Table 300.5. Table 300.5 depths shall also apply to low-voltage ELD airfield distribution system conduits (reference FAA-C-1391) that are entering buildings. Within 40 ft of a NAS building, or within a fenced enclosure closely associated with a building, NEC burial/coverage requirements for low-voltage (<600 V) conduit systems shall apply.

5.2.3.2.2 Rigid Metal Conduit

Galvanized ferrous rigid metal conduit (RMC) shall conform to UL 6. Ferrous RMC may be used in all locations above and below grade, and shall be used for all underground service conductors. All RMC shall be galvanized RMC or PVC coated galvanized RMC. When used in corrosive environments, RMC shall have a protective coating of PVC. The conduit shall extend at least 18 inches above grade or into the enclosure.

Elbows, couplings, and fittings used underground shall be protected as specified for conduit, or shall be field wrapped with 0.01-inch-thick pipe wrapping plastic tape applied with 50% overlap. All fittings used with ferrous rigid metal conduit shall be the threaded type, of the same material as the conduit. Where conduits enter/exit exterior junction boxes from the top, a water-tight hub such as Myers™ hub or equivalent connector shall be used. Where conduits enter enclosures without threaded hubs, double locknuts (one on each side of the enclosure wall) shall be used to securely bond the conduit to the enclosure. In addition, a grounding bushing shall be installed on the interior threaded end of the conduit to protect conductor insulation.

5.2.3.2.3 Intermediate Metal Conduit

Intermediate metal conduit (IMC) shall be zinc-coated steel, shall conform to UL Standard 1242, and shall bear the UL label. Ferrous IMC may be used in all locations above grade and below grade.

When used in corrosive environments, IMC shall have a protective coating of (1) Steel Structures

Painting Council Standard (SSPC-PS) 10.01, Hot-Applied Coal Tar Enamel Painting System; or (2) PVC. The conduit shall extend at least 18 inches above grade or into the enclosure.

Elbows, couplings, and fittings used underground shall be protected as specified for conduit, or shall be field wrapped with 0.01-inch-thick pipe wrapping plastic tape applied with 50% overlap. Where it is necessary to fabricate IMC bends in the field, the tooling required to fabricate those bends shall be specifically designed for IMC. All fittings shall be of the threaded type, of the same material as the conduit. Where conduits enter/exit exterior junction boxes from the top, a water-tight hub such as MyersTM hub or equivalent connector shall be used. Where conduits enter enclosures without threaded hubs, double locknuts (one on each side of the enclosure wall) shall be used to securely bond the conduit to the enclosure. In addition, a grounding bushing shall be installed on the interior threaded end of the conduit to protect conductor insulation.

5.2.3.2.4 Electrical Metallic Tubing

Electrical metallic tubing (EMT) shall be steel and otherwise conform to UL 797. EMT may be used only in dry interior locations, and where not subject to physical damage. EMT shall not be used on circuits above 600 volts. The maximum size of EMT shall be trade size 4 (metric designator 103).

Previous versions of this document limited EMT to trade size 3 (metric designator 78) due to structural integrity issues. Fittings used with EMT shall be standard compression-type fittings designed for this type of EMT, unless otherwise indicated. Set-screw-type fittings are not acceptable.

Where EMT enters enclosures without threaded hubs, an appropriate connector with threads and cast or machined (not sheet metal) locknut shall be used to securely bond the conduit to the enclosure. The connector body and locknut shall be installed so that firm contact is made on each side of the enclosure. In addition, the connectors shall have an insulated-throat, smooth bell-shaped end, or a grounding bushing.

5.2.3.2.5 Rigid Aluminum conduit

Aluminum conduit shall not be used for any installation except by special permission. Nonferrous ConduletsTM are acceptable.

5.2.3.2.6 Rigid Nonmetallic Conduit

Rigid nonmetallic conduit shall conform to UL 651. Rigid nonmetallic conduit used to protect electrical power conductors may only be used underground, or in concrete, or as a vertical riser to 6 inches above grade or floor surface for connection to metal conduit, and only when required by the contract drawings or specific job specifications. PVC fittings shall be used with PVC conduit and shall be assembled in accordance with manufacturer's instructions. A PVC threaded fitting with locknut and plastic bushing shall be used to connect PVC conduit to boxes or cabinets without threaded hubs. Rigid nonmetallic conduit may also be used to protect lightning protection system conductors and grounding conductors in accordance with FAA-STD-019.

Sweeps and elbows in underground installations shall be RMC or IMC.

5.2.3.2.7 Flexible metal conduit, including liquid-tight

Flexible metal conduit shall be ferrous and conform to Federal Specification A-A-55810.

Flexible metal conduit shall be used for terminal connections to motors or motor driven equipment, and in lengths only up to six (6) feet for other applications permitted by the NEC. A copper equipment grounding conductor (wire) shall be run with the circuit conductors; the conduit is not to be used as the equipment grounding conductor. The conduit connectors shall have a UL listed insulated-throat, with a smooth bell-shaped end, or a grounding bushing.

Liquid-tight flexible metal conduit shall be used outdoors and in wet locations.

Flexible metal conduit may be used under raised floor for branch circuits in lengths longer than six (6) feet in locations that meet all the requirements of Article 645 of the NEC. Conduit, fittings, and junction boxes installed under the raised floor shall be liquid-tight types.

5.2.3.2.8 Flexible nonmetallic conduit

Flexible nonmetallic conduit is permissible for exterior above grade applications in Navigational Aids (NAVAIDS) facilities such as ALSF, MALS, PAPI, or other systems designated by NAVAID PMO or Second Level engineering (AJW-14). This applies only in areas of high corrosion, extreme flexibility or frangibility.

5.2.3.2.9 Surface raceways

Nonmetallic surface raceways shall not be used. Surface metal raceways shall conform to UL 5.

Surface metal raceways shall be installed only in exposed, dry locations not subject to physical damage. Surface metal raceways shall meet NEC requirements; however, they shall not be used for circuits above 600 volts.

5.2.3.3 Wireways

Wireways shall conform to UL 870. Wireways shall only be installed in accessible locations.

Wireways installed in wet or outdoor locations shall be rated for these locations.

5.2.3.4 Cable rack systems

5.2.3.4.1 General

Cable rack systems shall be of the ladder or ventilated trough type conforming to NEMA VE 1 unless otherwise indicated. All components for each cable rack system shall be fabricated with commercial off the shelf (COTS) components from a single manufacturer. Cable rack support spacing shall be as recommended by the manufacturer except that in no case shall spacing of supports exceed 6 feet.

Cable racks shall be supported from structural members only.

5.2.3.4.2 Dimensions

Straight sections, bends, tees, offsets, reducers, etc., for ladder-type cable rack systems shall consist of 3-inch minimum side channels with suitable cross-channels (rungs) installed on 6-inch centers unless otherwise indicated. Straight sections, fittings, etc., for ventilated-type cable rack systems shall have 3-inch minimum high sides and a ventilated bottom with cross-pieces 2 inches (maximum) wide on 3-inch (maximum) centers and openings 2 inches (maximum) wide. Cable rack widths shall be as shown on the drawings.

5.2.4 Raceway support systems

5.2.4.1 General

Raceways shall be securely supported at intervals specified in the NEC Article 300.11, "Securing and Supporting," and fastened in place with pipe straps, wall brackets, hangers, or ceiling trapezes.

Fastenings shall be by wood screws, nails, or screw-type nails to wood; by toggle bolts on hollow masonry units; by expansion bolts on concrete or brick; by machine screws, welded threaded studs, or spring tension clamps on steel work. Nail-type nylon anchors or threaded studs driven by a power charge and provided with lock washers and nuts may be used in lieu of expansion bolts, machine screws, or wood screws. Threaded C clamps with retainers may be used. Raceways or pipe straps with a depth of more than 1 ½ inch in reinforced concrete beams, or with a depth of more than ¾ inch in reinforced concrete joists, shall not cut the main reinforcing bars. Holes not used shall be filled. In partitions of light steel construction, sheet-metal screws may be used. Raceways shall not be supported from sheet-metal roof decks. In suspended-ceiling construction, raceways shall not be fastened to the suspended-ceiling supports.

5.2.4.2 Telecommunication raceways

Telecommunication system raceways shall be installed in accordance with the previous requirements for conduit and tubing, with the additional requirements that no length of run shall exceed 50 feet for ½ inch and ¾ inch sizes, or 100 feet for 1-inch or larger sizes; and shall not contain more than two 90-degree bends or the equivalent. Pull or junction boxes shall be installed to comply with these limitations, whether or not indicated on the drawings. Bends in conduit of 1 inch and larger shall have minimum inside radii of 12 times the nominal conduit diameter.

5.2.5 Conductors

5.2.5.1 Uninsulated conductors

Uninsulated conductors shall be copper and in accordance with Federal Specification A-A-59551A.

5.2.5.2 Insulated conductors

Unless otherwise indicated, for general use in the FAA, insulated conductors shall be copper with thermoplastic or thermosetting insulation, typically type THWN or THWN-2. Insulated conductors shall be rated for 600 volts in accordance with Federal Specification A-A-59544. For other acceptable types of insulated conductors, consult NEC Table 310.4(A). Conductors sized 12 AWG and smaller for general use shall be solid. Stranded 12 AWG and smaller conductors are permitted when required for specific equipment installations. Stranded conductors shall be nationally approved testing laboratory (NATL) listed for the intended use. Minimum branch circuit conductor size shall be 12 AWG. If required for specific equipment installations such as with tight bends, other types of NATL-listed conductors (and compression fittings if required) may be used.

Control Cables/Wires--Minimum control wire size shall be 14 AWG unless otherwise required by manufacturer or noted on the drawings. Control wire may be stranded where recommended by the manufacturer, or where vibration and flexing may be encountered. NATL-approved or appropriate fittings shall be installed when required.

5.2.5.2.1 Fixture wiring

Fixture wiring shall be thermoplastic insulated copper, rated for 600 volts, in accordance with Federal Specification A-A-59544 and the NEC.

5.2.5.2.2 Conductor identification

All feeder and branch circuits, including neutral conductors, shall be identified at both ends of the conductor with panel and circuit number indicated. This shall be accomplished using vinyl self-laminating wraparound labels or shrink-embossed labels. Equipment grounding conductors shall be color-coded green. Conductors covered with green insulation with yellow, orange, violet, or red tracers shall be used for other grounding systems. Neutral conductors shall be white insulated for 208Y/120 and 120/240 volt systems, and gray insulated for 480Y/277 volt systems. For conductors 4 AWG and larger, and where appropriate insulation color is not available, use color-coded tape, half lapped for a minimum length of 3 inches. Switch-leg conductors shall be consistently identified within a facility. All conductor color codes including reidentified conductors shall be visible at all junction boxes, pull boxes, panelboards, outlets, switches, at access locations in closed raceways, every three (3) feet in open raceways, under all raised floors, and at all terminations.

5.2.5.2.3 Color Coding for Ungrounded Conductors

5.2.5.2.3.1 120, 120/240, 208Δ, 208Y/120 Voltage Systems Standard practice for FAA installations is (1) black for 120 volt systems; (2) black and red for 120/240 volt systems; (3) black (phase A), red (phase B), and blue (phase C) for 208Δ and 208Y/120 volt 3-phase systems. This color scheme is generally used within the United States. Phase conductor color coding shall be continuous throughout the facility on each phase conductor to its point of use so that the conductor phase connection is readily identifiable.

5.2.5.2.3.2 480Δ, 480Y/277 Voltage Systems To ensure safety and proper operation of equipment, only one system shall be used within a facility.

For work at an existing facility, the color coding to be used shall match the existing facility color code.

For new FAA facilities, the FAA historical practice of yellow-brown-orange for phase A, B, C is preferred; local practice brown-orange-yellow for phase A, B, C is permitted. Phase conductor color coding shall be continuous throughout the facility on each phase conductor to its point of use so that the conductor phase connection is readily identifiable.

5.2.5.2.3.3 Direct Current Systems

Standard use in the electrical, automotive, and nautical arenas, including the approved National DC Bus System equipment, is red for dc positive and black for dc negative. These standard colors shall be used for all FAA installations.

5.2.5.3 Connectors and Splices

Splices shall be made only at outlets, junction boxes, or accessible raceways. Splicing of ungrounded conductors in panelboards is not permitted. All splices shall be accessible. Splices shall be made with solderless connectors conforming to UL 486A-486B, UL 486C, and UL 486E. Insulated twist-on wire connectors may only be used to splice conductors sized 10 AWG and smaller. Compression connectors shall be used to splice conductors 8 AWG and larger. All splices, including those made with insulated twist-on wire connectors, shall be insulated with electrical tape or shrink tubing to a level equal to that of the factory-insulated conductors. All underground splicing shall be accomplished in accordance with FAA-C-1391. To increase the reliability of power for NAS critical services, new feeder and branch conductors supporting these services shall not be spliced. Splices are not recommended, but may be used for modification work on existing systems. Where splices are used in other systems, such splices shall be approved by FAA in advance, and documented on facility drawings.

Connectors shall be listed for use with the conductors. Connectors for use with Class C and finer stranding shall be wire compression connectors or a pressure washer type lug; lugs with screw-only compression are not allowed. Consult manufacturer for specific recommendations for termination of fine stranded wire.

When twist-on wire connectors are used, wires must be pre-twisted.

5.2.6 Metal-Clad Cable: Type MC

The installation of Metal-Clad Cable: Type (MC) installation must comply with the NEC. All metal-clad cable shall be UL listed with a steel sheath. Aluminum sheathing is not allowed. Both ends of the cable shall be terminated using UL-listed saddle or stirrup type fittings. Metal-Clad Cable shall include a separate internal equipment grounding conductor (wire); the metallic sheath is not to be used as the equipment grounding conductor.

5.2.6.1 Type MC installed in cable tray

When installed in cable tray, the following conditions must also be met:

a. Type MC Cable shall be installed in metallic cable tray.

b. MC Cable shall be separated from communication, signal, and control cables per

ANSI/TIA/EIA 569, Table 3.

c. The bend radius of Type MC Cable shall comply with applicable code and manufacturer guidance.

d. MC Cable can be run with other power conductors in accordance with code.

5.2.6.2 Type MC installed in other than cable tray

When installed in other than cable tray, or freely supported as allowed by code, MC Cable shall be:

a. Used only in existing construction, or as otherwise permitted in writing for a specific use.

b. Used only for branch circuits.

c. Used for essential and nonessential loads only, when installed in areas that are not readily accessible such as wall cavities or ceilings, except as otherwise permitted in writing for a specific use.

d. Permitted for specialized installations with proper engineering justification.

5.2.6.3 Fire pump wiring

Fire pump and fire life safety (FLS) feeder circuits shall be 2-hour fire rated to comply with NEC Article 700. NATL-listed fire-rated cables are permitted to be used to feed the fire pump. The outer power cable shield may be used for ground if (1) it is permitted by the manufacturer, and

(2) if its proximity to electronic equipment does not affect equipment performance.

5.3 Boxes

Boxes shall be either the cast-metal threaded-hub type conforming to UL 514A and UL5l4B, galvanized steel type conforming to UL 514A and UL 514B, or metal outlet boxes conforming to NEMA OS 1. All enclosures shall conform to NEMA standards.

5.3.1 Applications

Boxes shall be provided in the wiring or raceway system for pulling wires, making connections, and mounting devices or fixtures. All outdoor boxes shall be rated suitable for the environment. In hazardous areas, boxes shall be rated suitable for the hazardous locations. Each electrical outlet box shall have a machine screw that fits into a tapped hole in the box for the ground connection. Boxes shall be sized in accordance with the NEC. Boxes for mounting lighting fixtures shall not be less than 4 inches square. Boxes installed for concealed wiring shall be provided with extension rings or plaster covers. The front edge of the box shall be flush or recessed not more than 1/4-inch from the finished wall surface. Boxes for use in masonry-block or tile walls shall be square-cornered tile-type, or standard boxes having square-cornered tile-type covers. Cast-metal boxes installed in wet locations and boxes installed flush with exterior surfaces shall be gasketed. Separate boxes shall be provided for flush or recessed fixtures where required by the fixture terminal operating temperature. Fixtures shall be readily removable for access to the boxes unless ceiling access panels are provided. Boxes for fixtures on suspended ceilings shall be supported independently of the ceiling supports. Boxes shall not be supported from sheet-metal roof decks. Nonmetallic boxes may be used only with nonmetallic raceway systems.

5.3.2 Supports

Boxes and supports shall be securely fastened to wood with wood screws, nails,…