Article 300-General Requirements for Wiring Methods and Materials

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

Cables laid in wood notches require protection against nails or screws by using a steel plate at least _____ in. thick, installed before the building finish is applied.

1/16

When installing PVC conduit underground without concrete cover, there shall be a minimum _____ in. of cover.

18

Where raceways contain insulated circuit conductors _____ AWG and larger, the conductors shall be protected from abrasion during and after installation by an identified fitting providing a smoothly rounded insulating surface.

4

Wiring methods permitted in the ceiling areas used for environmental air include _____.

electrical metallic tubing, FMC of any length, and RMC without an overall nonmetallic covering

Where corrosion protection is necessary for ferrous metal equipment and the conduit is threaded in the field, the threads shall be coated with a(an) _____ electrically conductive, corrosion-resistant compound.

approved

Where independent support wires of a suspended ceiling assembly are used to support raceways, cable assemblies, or boxes above a ceiling, they shall be secured at _____ end(s).

both

A(An) _____ with an integral bushed opening shall be used at the end of a conduit or other raceway that terminates underground where the conductors or cables emerge as a direct burial wiring method.

bushing or terminal fitting

The independent support wires for supporting electrical wiring methods in a fire-rated ceiling assembly shall be distinguishable from fire-rated suspended-ceiling framing support wires by _____.

color, tagging, and other effective means

At least _____ support method(s) shall be provided for each conductor at the top of the vertical raceway or as close to the top as practical if the vertical rise exceeds the values in Table 300.19(A).

one

The requirement to run all paralleled circuit conductors within the same _____ applies separately to each portion of the paralleled installation.

raceway or auxiliary gutter, cable tray or trench, and cable or cord

Electrical equipment with a metal or nonmetallic enclosure listed for use within an air-handling space and having low _____ properties, and associated wiring material suitable for the ambient temperature can be installed within an air-handling space (plenum).

smoke and heat release

All conductors of the same circuit shall be _____, unless otherwise specifically permitted in the Code.

in the same raceway or cable or be in close proximity in the same trench

A listed expansion/deflection fitting or other approved means shall be used where a raceway crosses a _____ intended for expansion, contraction or deflection used in buildings, bridges, parking garages, or other structures.

structural joint

Wiring methods installed behind panels that allow access shall be _____ according to their applicable articles.

supported

A box or conduit body shall not be required for conductors in handhole enclosures, except where connected to electrical equipment.

true

In accordance with Article 300, a(an) _____ is considered a plenum space.

space over a hung ceiling used for environmental air-handling purposes

The interior of underground raceways shall be considered a _____ location.

wet

Where raceways are installed in wet locations above grade, the interior of these raceways shall be considered a _____ location.

wet

Where nails or screws are likely to penetrate nonmetallic-sheathed cable or ENT installed through metal framing members, a steel sleeve, steel plate, or steel clip not less than _____ in. in thickness shall be used to protect the cable or tubing.

1/16

What is the minimum cover requirement for Type UF cable supplying power to a 120V, 15A GFCI-protected circuit outdoors under a driveway of a one-family dwelling?

12 in

Electrical installations in hollow spaces shall be made so not to increase the spread of fire, such as boxes installed in a wall cavity on opposite sides of a fire rated wall where a minimum horizontal separation of _____ in. usually applies between boxes.

24

_____ is defined as the shortest distance measured between a point on the top surface of direct-burial cable and the top surface of the finished grade.

Cover

Where raceways contain 4 AWG or larger insulated circuit conductors entering a cabinet, box, enclosure, or raceway, the conductors shall be protected by _____.

an identified fitting that provides a smooth rounded insulating surface, a listed metal fitting that has smooth rounded edges, and threaded hubs that provide a smooth rounded or flared entry.

Conductors in raceways shall be _____ between outlets, boxes, devices, and so forth.

continuous

Raceways, cable armors, and cable sheaths shall be _____ between cabinets, boxes, fittings, or other enclosures or outlets.

continuous

Each direct-buried single conductor cable shall be located _____ in the trench to the other single conductor cables in the same parallel set of conductors, including equipment grounding conductors.

in close proximity

Raceways shall be _____ between outlet, junction, or splicing points prior to the installation of conductors.

installed complete

Type MC Cable _____ for direct burial or concrete encasement shall be permitted under a building without installation in a raceway in accordance with 330.10(A)(5).

listed

Where Type NM cable passes through factory or field openings in metal members, it shall be protected by _____ bushings or _____ grommets that cover metal edges.

listed

The provisions of Article 300 apply to the conductors that form an integral part of equipment or_____________________.

listed utilization equipment

Metal raceways, cable armor, and other metal enclosures shall be _____ joined together into a continuous electric conductor so as to provide effective electrical continuity.

metallically

Wiring methods and cabling systems, listed for use in other spaces used for environmental air (plenums), shall be permitted to be installed in ducts specifically fabricated for environmental air-handling purposes _____.

only if necessary to connect to equipment or devices associated with the direct action upon or sensing of the contained air, if the total length of such wiring methods or cabling systems does not exceed 4 ft, or where illumination is necessary to facilitate maintenance and repair

The space above a hung ceiling used for environmental air-handling purposes is an example of _____, and the wiring limitations of _____ apply.

other space used for environmental air (plenum), 300.22(C)

Conductors in ferrous metal raceways or enclosures shall be arranged so as to avoid heating the surrounding ferrous metal by alternating-current induction. To accomplish this, the _____ conductor(s) shall be grouped together.

phase, grounded, and equipment grounding

Short sections of raceways used for _____ shall not be required to be installed complete between outlet, junction, or splicing points.

protection of cables from physical damage

Where portions of a cable raceway or sleeve are subjected to different temperatures and condensation is known to be a problem, the _____ shall be sealed to prevent the circulation of warm air to a colder section of the raceway or sleeve.

raceway or sleeve

All conductors of the same circuit, including the grounded and equipment grounding conductors and bonding conductors shall be contained within the same _____, unless otherwise permitted elsewhere in the Code.

raceway, cable, and trench

Backfill used for underground wiring shall not damage _____ or prevent adequate compaction of fill or contribute to corrosion.

raceways, cables, and conductors

Conduits or raceways through which moisture may contact live parts shall be _____ at either or both ends.

sealed or plugged

Electrical installations in hollow spaces, vertical shafts, and ventilation or air-handling ducts shall be made so that the possible spread of fire or products of combustion will not be _____.

substantially increased

A box or conduit body shall not be required for splices and taps in direct-buried conductors and cables as long as the splice is made with a splicing device that is identified for the purpose.

true

A box or conduit body shall not be required where cables enter or exit from conduit or tubing that is used to provide cable support or protection against physical damage

true

Section 300.22(C) applies to spaces not specifically fabricated for environmental air-handling purposes but used for air-handling purposes such as the space over a hung ceiling.

true

Wiring methods and equipment installed behind suspended-ceiling panels shall be arranged and secured to allow access to the electrical equipment.

true

A cable, raceway, or box installed under metal-corrugated sheet roof decking shall be supported so the top of the cable, raceway, or box is not less than _____ from the lowest surface of the roof decking to the top of the cable, raceway, or box.

1 1/2 in.

Direct-buried service conductors that are not encased in concrete and that are buried 18 in. or more below grade shall have their location identified by a warning ribbon placed in the trench at least _____ in. above the underground installation.

12

What is the minimum cover requirement for direct burial Type UF cable installed outdoors that supplies a 120V, 30A circuit?

24 in

When the opening to an outlet, junction, or switch point is less than 8 in. in any dimension, each conductor shall be long enough to extend at least _____ in. outside the opening of the enclosure.

3

Rigid metal conduit that is directly buried outdoors shall have at least _____ in. of cover.

6

Type UF cable used with a 24V landscape lighting system can have a minimum cover of _____ in.

6

Where direct-buried conductors and cables emerge from grade, they shall be protected by enclosures or raceways to a point at least _____ above finished grade.

8 ft

A vertical run of 4/0 AWG copper shall be supported at intervals not exceeding _____ ft.

80

_____ is a nonferrous, nonmagnetic metal that has no heating due to hysteresis heating.

Aluminum

When installed under metal-corrugated sheet roof decking, the rules for spacing from roof decking_____________equally to rigid metal conduit and intermediate metal conduit.

DO NOT apply

Which of the following metal parts shall be protected from corrosion?

Ferrous metal raceways, Ferrous metal elbows, and Ferrous boxes.

Wiring methods that are permitted to be installed in ducts fabricated for environmental air include _____.

MC cable without an overall nonmetallic covering, EMT (electrical metallic tubing), and RMC (rigid metal conduit)

_____ shall be permitted to support the wiring methods and equipment permitted to be used in other spaces used for environmental air (plenum).

Metal cable tray systems

Where an exit enclosure is required to be separated from the building, only electrical wiring methods serving equipment permitted by the _____ in the exit enclosure shall be installed within the exit enclosure.

authority having jurisdiction

Openings around electrical penetrations into or through fire-resistant-rated walls, partitions, floors, or ceilings shall _____ to maintain the fire-resistance rating.

be firestopped using approved methods

Where portions of cable raceways or sleeves are required to be sealed due to different temperatures, sealants shall be identified for use with _____, a bare conductor, a shield, or other components.

cable and conductor insulation

Direct-buried conductors or cables ____________________ without the use of splice boxes when the splice or tap is made in accordance with 110.14(B).

can be spliced or tapped

Connections, taps, or extensions made from paralleled conductors shall connect to all ____________________.

conductors of the paralleled set

Raceways can be used as a means of support of Class 2 circuit conductors or cables that _____________________.

connect to the same equipment

Equipment and devices shall only be permitted within ducts or plenum chambers specifically fabricated to transport environmental air if necessary for their direct action upon, or sensing of, the _____.

contained air

No wiring of any type shall be installed in ducts used to transport _____.

dust, flammable vapors, and loose stock

Direct-buried conductors, cables, or raceways, which are subject to movement by settlement or frost, shall be arranged to prevent damage to the _____ or to equipment connected to the raceways.

enclosed conductors

Conductors of ac and dc circuits, rated 1,000V or less, shall be permitted to occupy the same _____ provided that all conductors have an insulation rating equal to the maximum voltage applied to any conductor.

enclosure, cable, and raceway

In multiwire branch circuits, the continuity of the _____ shall not be dependent upon the device connections.

grounded conductor

Spare or unused raceways shall be sealed with sealants _____ for use with the cable insulation, conductor insulation, bare conductor, shield, or other components.

identified

Underground cable and conductors installed under a building shall be _____.

in a raceway

Where Type NM cables pass through cut or drilled slots or holes in metal members, the cable shall be protected by _____ which are installed in the opening prior to the installation of the cable and which securely cover all metal edges.

listed bushings or grommets

Conductors installed in nonmetallic raceways run underground shall be permitted to be arranged as _____ installations. The raceways shall be installed in close proximity, and the conductors shall comply with 300.20(B).

neutral, grounded conductor, and isolated phase

Where cables or nonmetallic raceways are installed through bored holes in joists, rafters, or wood members, holes shall be bored so that the edge of the hole is _____ the nearest edge of the wood member.

not less than 1 1/4 in. from

Cable wiring methods shall not be used as a means of support for _____.

other cables, raceways, and nonelectrical equipment

The number and size of conductors permitted in a raceway is limited to _____.

permit heat to dissipate, prevent damage to insulation during installation, and prevent damage to insulation during removal of conductors

Raceways, cable assemblies, boxes, cabinets, and fittings shall be _______________.

securely fastened in place

Electrical wiring within the cavity of a fire-rated floor-ceiling or roof-ceiling assembly shall not be supported by__________________________________.

the ceiling assembly or ceiling support wires

Raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, fittings, supports, and support hardware shall be of materials suitable for _____.

the environment in which they are to be installed

Raceways shall be provided with expansion, expansion-deflection, or deflection fittings where necessary to compensate for ___________________.

thermal expansion, deflection, and contraction

Fittings and connectors shall be used only with the specific wiring methods for which they are designed and listed.

true

Prewired raceway assemblies shall be used only where specifically permitted in the NEC for the applicable wiring method.

true


Kaugnay na mga set ng pag-aaral

Principles of Management - Chapter 12

View Set

NURS 404: Evolve questions Week 1-2

View Set

Managing Azure Subscriptions and Resources

View Set