Understanding NEC Articles 242 & 300

Question 1

Article _____ provides the general requirements installation requirements and connection requirements for overvoltage protection and overvoltage protective devices.
Answer 1: 242
Answer 2: 285
Answer 3: 286
Answer 4: 287

Answer 1

Answer 1: 242

242.1

Question 2

Surge-protective devices shall be _____.
Answer 1: listed
Answer 2: identified
Answer 3: marked
Answer 4: labeled

Answer 2

Answer 1: listed

242.6

Question 3

A surge-protective device shall not be installed in circuits over _____.
Answer 1: 480V
Answer 2: 600V
Answer 3: 1000V
Answer 4: 4160V

Answer 3

Answer 3: 1000V

242.12(1)

Question 4

Type 1 SPDs shall be permitted to be connected on the supply side of the _____ disconnect.
Answer 1: service
Answer 2: feeder
Answer 3: branch-circuit
Answer 4: outside feeder

Answer 4

Answer 1: service

242.13(A)(1)

Question 5

A _____ surge-protective device is permitted to be connected on either the line or load side of a service disconnect overcurrent device.
Answer 1: Type 1
Answer 2: Type 2
Answer 3: Type 3
Answer 4: Type 4

Answer 5

Answer 1: Type 1

242.13(A)

Question 6

Type 2 SPDs shall be connected at the building or structure anywhere on the load side of the _____.
Answer 1: first overcurrent device
Answer 2: service attachment point
Answer 3: meter socket
Answer 4: transformer

Answer 6

Answer 1: first overcurrent device

242.14(B)

Question 7

The conductors used to connect the surge-protective device to the line or bus and to ground shall not be any longer than _____ and shall avoid unnecessary bends.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: necessary

Answer 7

Answer 4: necessary

242.24

Question 8

Conductors for ac and dc circuits under 1000V ac and 1500V dc can occupy the same _____ provided that all conductors have an insulation rating equal to the maximum voltage applied to any conductor.
Answer 1: equipment wiring enclosure
Answer 2: cable
Answer 3: raceway
Answer 4: any of these

Answer 8

Answer 4: any of these

300.3(C)(1)

Question 9

The requirement to run all paralleled circuit conductors within the same _____ applies separately to each portion of the paralleled installation.
Answer 1: raceway or auxiliary gutter
Answer 2: cable tray or trench
Answer 3: cable or cord
Answer 4: all of these

Answer 9

Answer 4: all of these

300.3(B)(1)

Question 10

Conductors installed in nonmetallic raceways run underground shall be permitted to be arranged as isolated _____ installations. The raceways shall be installed in close proximity and the conductors shall comply with 300.20(B).
Answer 1: neutral
Answer 2: grounded conductor
Answer 3: phase
Answer 4: all of these

Answer 10

Answer 4: all of these

300.3(B)(1) Ex

Question 11

Where a cable or raceway-type wiring method is installed through bored holes in joists rafters or wood members the holes shall be bored so that the edge of the hole is _____ the edges of the wood member.
Answer 1: not less than 1¼ in. from
Answer 2: immediately adjacent to
Answer 3: not less than 1⁄16 in.
Answer 4: 90° away from

Answer 11

Answer 1: not less than 1¼ in. from

300.4(A)(1) and Ex 1

Question 12

Cables laid in wood notches require protection against nails or screws by using a steel plate at least _____ thick installed before the building finish is applied.
Answer 1: 1⁄16 in.
Answer 2: 1⁄8 in.
Answer 3: ¼ in.
Answer 4: ½ in.

Answer 12

Answer 1: 1⁄16 in.

300.4(A)(2)

Question 13

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.
Answer 1: anti-short devices
Answer 2: sleeves
Answer 3: plates
Answer 4: listed bushings or grommets

Answer 13

Answer 4: listed bushings or grommets

300.4(B)(1)

Question 14

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 thickness shall be used to protect the cable or tubing.
Answer 1: 1⁄16 in.
Answer 2: 1⁄8 in.
Answer 3: ½ in.
Answer 4: ¾ in.

Answer 14

Answer 1: 1⁄16 in.

300.4(B)(2)

Question 15

Where cables and nonmetallic raceways are installed parallel to framing members the nearest outside surface of the cable or raceway shall be _____ the nearest edge of the framing member where nails or screws are likely to penetrate.
Answer 1: not less than 1¼ in. from
Answer 2: immediately adjacent to
Answer 3: not less than 1⁄16 in. from
Answer 4: 90 degrees away from

Answer 15

Answer 1: not less than 1¼ in. from

300.4(D)

Question 16

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.
Answer 1: ½ in.
Answer 2: 1 in.
Answer 3: 1½ in.
Answer 4: 2 in.

Answer 16

Answer 3: 1½ in.

300.4(E)

Question 17

When installed under metal-corrugated sheet roof decking _____ and intermediate metal conduit with listed steel or malleable iron fittings and boxes shall not be required to comply with 300.4(E).
Answer 1: rigid metal conduit
Answer 2: electrical metallic tubing
Answer 3: Schedule 80 PVC
Answer 4: all of these

Answer 17

Answer 1: rigid metal conduit

300.4(E) Ex 1

Question 18

Conduit bushings installed to protect insulated conductors _____ or larger contained within raceways that are constructed wholly of insulating material shall not be used to secure a fitting or raceway.
Answer 1: 4 AWG
Answer 2: 6 AWG
Answer 3: 8 AWG
Answer 4: 10 AWG

Answer 18

Answer 1: 4 AWG

300.4(G)

Question 19

Where raceways contain 4 AWG or larger insulated circuit conductors and these conductors enter a cabinet a box an enclosure or a raceway the conductors shall be protected from abrasion during and after installation by an identified fitting providing a smoothly rounded _____ surface.
Answer 1: fiberglass
Answer 2: plastic
Answer 3: insulating
Answer 4: gray

Answer 19

Answer 3: insulating

300.4(G)(1)

Question 20

Electrical metallic tubing that is directly buried under a two-family dwelling driveway shall have at least _____ of cover.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: 24 in.

Answer 20

Answer 3: 18 in.

300.5(A) Table Column 2

Question 21

Rigid metal conduit that is directly buried outdoors shall have at least _____ of cover.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: 24 in.

Answer 21

Answer 1: 6 in.

300.5(A) Table Column 2

Question 22

A PVC raceway covered in 2 in. of concrete is required to have a minimal buried depth of _____.
Answer 1: 6 in.
Answer 2: 18 in.
Answer 3: 12 in.
Answer 4: 24 in.

Answer 22

Answer 3: 12 in.

300.5(A) Table Column 3

Question 23

The minimum cover requirement for Type UF cable that supplies a 120V 15A GFCI-protected circuit under a driveway of a one-family dwelling is _____.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 16 in.
Answer 4: 24 in.

Answer 23

Answer 2: 12 in.

300.5(A) Table Column 4

Question 24

For a dwelling location direct buried cables that are GFCI protected at no more than 20A shall have a cover of _____.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: 24 in.

Answer 24

Answer 2: 12 in.

300.5(A) Table Column 4

Question 25

Type UF cable used with a 24V landscape lighting system can have a minimum cover of _____.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: 24 in.

Answer 25

Answer 1: 6 in.

300.5(A) Table Column 5

Question 26

The interior of underground raceways shall be considered a _____ location.
Answer 1: wet
Answer 2: dry
Answer 3: damp
Answer 4: corrosive

Answer 26

Answer 1: wet

300.5(B)

Question 27

Underground cable and conductors installed under a building shall be _____.
Answer 1: in the same trench
Answer 2: in a raceway
Answer 3: encased in concrete
Answer 4: under at least 2 in. of concrete

Answer 27

Answer 2: in a raceway

300.5(C)

Question 28

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).
Answer 1: listed
Answer 2: identified
Answer 3: tagged
Answer 4: labeled

Answer 28

Answer 1: listed

300.5(C) Ex 2

Question 29

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.
Answer 1: 3 ft
Answer 2: 6 ft
Answer 3: 8 ft
Answer 4: 10 ft

Answer 29

Answer 3: 8 ft

300.5(D)(1)

Question 30

Backfill used for underground wiring shall not damage _____ or prevent adequate compaction of fill or contribute to corrosion.
Answer 1: raceways
Answer 2: cables
Answer 3: conductors
Answer 4: any of these

Answer 30

Answer 4: any of these

300.5(F)

Question 31

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.
Answer 1: splice kit
Answer 2: connector
Answer 3: adapter
Answer 4: bushing or terminal fitting

Answer 31

Answer 4: bushing or terminal fitting

300.5(H)

Question 32

All conductors of the same circuit shall be _____ unless otherwise specifically permitted in the Code.
Answer 1: bonded
Answer 2: grounded
Answer 3: the same size
Answer 4: in the same raceway or cable or be in close proximity in the same trench

Answer 32

Answer 4: in the same raceway or cable or be in close proximity in the same trench

300.5(I) and 300.3(B)

Question 33

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.
Answer 1: cable
Answer 2: raceway
Answer 3: enclosed conductors
Answer 4: expansion fitting

Answer 33

Answer 3: enclosed conductors

300.5(J)

Question 34

Raceways cable trays cablebus auxiliary gutters cable armor boxes cable sheathing cabinets enclosures (other than surrounding fences and walls) elbows couplings fittings supports and support hardware shall be of materials suitable for _____.
Answer 1: corrosive locations
Answer 2: wet locations
Answer 3: the environment in which they are to be installed
Answer 4: damp locations

Answer 34

Answer 3: the environment in which they are to be installed

300.6

Question 35

Where corrosion protection is necessary and the conduit is threaded anywhere other than at the factory where the product is listed the threads shall be coated with a(an) _____ electrically conductive corrosion-resistant compound.
Answer 1: marked
Answer 2: listed
Answer 3: labeled
Answer 4: approved

Answer 35

Answer 4: approved

300.6(A)

Question 36

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.
Answer 1: low temperature conditions
Answer 2: high temperature conditions
Answer 3: a stranded conductor
Answer 4: cable insulation or conductor insulation

Answer 36

Answer 4: cable insulation or conductor insulation

300.7(A)

Question 37

Raceways shall be provided with expansion expansion-deflection or deflection fittings where necessary to compensate for thermal expansion deflection and _____.
Answer 1: contraction
Answer 2: warping
Answer 3: bending
Answer 4: cracking

Answer 37

Answer 1: contraction

300.7(B)

Question 38

Where raceways are installed in wet locations above grade the interior of these raceways shall be considered a _____ location.
Answer 1: wet
Answer 2: dry
Answer 3: damp
Answer 4: corrosive

Answer 38

Answer 1: wet

300.9

Question 39

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).
Answer 1: one
Answer 2: both
Answer 3: the line and load
Answer 4: at the attachment to the structural member

Answer 39

Answer 2: both

300.11(B)

Question 40

Wiring located within the cavity of a fire-rated floor-ceiling or roof-ceiling assembly shall not be secured to or supported by the ceiling assembly including the ceiling support _____.
Answer 1: wires
Answer 2: hangers
Answer 3: rods
Answer 4: none of these

Answer 40

Answer 1: wires

300.11(B)(1)

Question 41

Raceways may be used as a means of support where the raceway contains power-supply conductors for electrically controlled equipment and is used to _____ Class 2 or Class 3 circuit conductors or cables that are solely for the purpose of connection to the equipment control circuits.
Answer 1: support
Answer 2: secure
Answer 3: strap
Answer 4: none of these

Answer 41

Answer 1: support

300.11(C)(2)

Question 42

Cable wiring methods shall not be used as a means of support for _____.
Answer 1: other cables
Answer 2: raceways
Answer 3: nonelectrical equipment
Answer 4: any of these

Answer 42

Answer 4: any of these

300.11(D)

Question 43

Raceways cable armors and cable sheaths shall be _____ between cabinets boxes conduit bodies fittings or other enclosures or outlets.
Answer 1: continuous
Answer 2: protected
Answer 3: buried
Answer 4: encased in concrete

Answer 43

Answer 1: continuous

300.12

Question 44

Mechanical continuity of raceways cable armors and cable sheaths as required by 300.12 does not apply to _____.
Answer 1: Type MI Cable
Answer 2: Type MC Cable
Answer 3: short sections of raceways used for support or protection of cable assemblies
Answer 4: any of these

Answer 44

Answer 3: short sections of raceways used for support or protection of cable assemblies

300.12 Ex 1

Question 45

Conductors in raceways shall be _____ between outlets boxes devices and so forth.
Answer 1: continuous
Answer 2: installed
Answer 3: copper
Answer 4: in conduit

Answer 45

Answer 1: continuous

300.13(A)

Question 46

In multiwire branch circuits the continuity of a(an) _____ shall not depend on device connections such as lampholders receptacles and so forth.
Answer 1: ungrounded conductor
Answer 2: grounded conductor
Answer 3: grounding electrode
Answer 4: raceway

Answer 46

Answer 2: grounded conductor

300.13(B)

Question 47

Where the opening to an outlet junction or switch point is less than 8 in. in any dimension the length of free conductor of each conductor spliced or unspliced shall extend at least _____ outside the opening of the enclosure.
Answer 1: 1 in.
Answer 2: 3 in.
Answer 3: 6 in.
Answer 4: 12 in.

Answer 47

Answer 2: 3 in.

300.14

Question 48

Fittings and connectors shall be used only with the specific wiring methods for which they are _____ and listed.
Answer 1: designed
Answer 2: identified
Answer 3: marked
Answer 4: labeled

Answer 48

Answer 1: designed

300.15

Question 49

The number and size of conductors and cables in any raceway shall not be more than will _____.
Answer 1: permit dissipation of heat
Answer 2: prevent damage to insulation during installation
Answer 3: prevent damage to insulation during removal of conductors
Answer 4: all of these

Answer 49

Answer 4: all of these

300.17

Question 50

Raceways shall be _____ between outlet junction or splicing points prior to the installation of conductors.
Answer 1: installed complete
Answer 2: tested for ground faults
Answer 3: a minimum of 80 percent complete
Answer 4: torqued

Answer 50

Answer 1: installed complete

300.18(A)

Question 51

_____ is(are) a nonferrous nonmagnetic metal that has no heating due to hysteresis heating.
Answer 1: Steel
Answer 2: Iron
Answer 3: Aluminum
Answer 4: all of these

Answer 51

Answer 3: Aluminum

300.20(B) Informational Note

Question 52

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 _____.
Answer 1: substantially increased
Answer 2: allowed
Answer 3: inherent
Answer 4: possible

Answer 52

Answer 1: substantially increased

300.21

Question 53

Electrical installations in hollow spaces shall be made so as to not 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 _____ usually applies between boxes.
Answer 1: 6 in.
Answer 2: 12 in.
Answer 3: 18 in.
Answer 4: 24 in.

Answer 53

Answer 4: 24 in.

300.21 and Informational Note

Question 54

No wiring of any type shall be installed in ducts used to transport _____.
Answer 1: dust
Answer 2: flammable vapors
Answer 3: loose stock
Answer 4: all of these

Answer 54

Answer 4: all of these

300.22(A)

Question 55

The space above a hung ceiling used for environmental air-handling purposes is an example of _____.
Answer 1: a specifically fabricated duct used for environmental air [300.22(B)]
Answer 2: other space used for environmental air (plenum) [300.22(C)]
Answer 3: a supply duct used for environmental air [300.22(B)]
Answer 4: a supplemental return duct used for environmental air [300.22(C)]

Answer 55

Answer 2: other space used for environmental air (plenum) [300.22(C)]

300.22(C) Informational Note 1

Question 56

Wiring methods permitted in ceiling areas used for environmental air include _____.
Answer 1: electrical metallic tubing
Answer 2: flexible metallic conduit
Answer 3: RMC without an overall nonmetallic covering
Answer 4: all of these

Answer 56

Answer 4: all of these

300.22(C)(1)

Question 57

Electrical equipment with a metal enclosure or electrical equipment with a nonmetallic enclosure listed for use within an air-handling space and having low _____ release properties are permitted to be installed in other spaces used for environmental air.
Answer 1: resistance
Answer 2: impedance
Answer 3: and high temperature
Answer 4: smoke and heat

Answer 57

Answer 4: smoke and heat

300.22(C)(3)

Question 58

Cables raceways and _____ installed behind suspended-ceiling panels shall be arranged and secured to allow access to the electrical equipment.
Answer 1: equipment
Answer 2: appliances
Answer 3: cords
Answer 4: conductors

Answer 58

Answer 1: equipment

300.23

Question 59

Where an exit enclosure (stair tower) is required to have a fire-resistance rating only electrical wiring methods serving equipment permitted by the _____ in the exit enclosure shall be installed within the exit enclosure.
Answer 1: fire code official
Answer 2: building code official
Answer 3: authority having jurisdiction
Answer 4: electrical engineer

Answer 59

Answer 3: authority having jurisdiction

300.25

Question 60

Where an exit enclosure (stair tower) is required to have _____ lighting on outside exterior doorways from the exit enclosure luminaires shall be permitted to be supplied from the inside of the exit enclosure.
Answer 1: normal
Answer 2: emergency
Answer 3: egress
Answer 4: standby

Answer 60

Answer 3: egress

300.25 Ex