Code, Standards, and Practices 2, Level II - 2020 Lesson 4

Match the title to the NEC reference associated with the provisions that generally allow conductors of sizes 1/0 AWG and larger to be connected in parallel.

Ampacity Adjustment: 310.10(G)(4) Bonding Jumpers: 310.10(G)(6) Conductor and Installation Characteristics: 310.10(G)(2) Equipment Grounding Conductors: 310.10(G)(5) Separate Cables or Raceways: 310.10(G)(3)

Match the title with the NEC reference associated with the provisions related to Uses Permitted for the conductors described in 310.4, where they are used in any of the wiring methods covered in Chapter 3 and as specified in their respective tables in the NEC, or as permitted elsewhere in the NEC.

Conductors in Parallel: 310.10 (G) Corrosive Conditions: 310.10 (F) Direct-Burial Conductors: 310.10 (E)

Match the title with the NEC reference associated with the provisions related to uses permitted for the conductors described in Section 310.4, where they are used in any of the wiring methods covered in Chapter 3 and as specified in their respective tables in the NEC, or as permitted elsewhere in the NEC.

Dry and Damp Locations: 310.10 (B) Dry Locations: 310.10 (a) Exposed to Direct Sunlight: 310.10 (D) Wet Locations: 310.10 (C)

Match the title to the NEC reference associated with the provisions related to conductor identification.

Equipment Grounding Conductors 310.6(B) Grounded Conductors 310.6(A) Ungrounded Conductors 310.6(C)

Type letter MTW has an application provision as machine tool wiring and has a maximum operating temperature of 60°C where used in dry locations.

False

Match the title to the part of Article 310.

General 1 Installation III Construction II

Note 5 of Table 310.4(A) indicates to see Section 340.80 for ampacity limitation.

True

The application provision for type letter SIS is switchboard and switchgear wiring only.

True

The minimum size of conductors for voltage ratings up to and including 2,000 volts shall be ? copper or ? aluminum or copper-clad aluminum, except as permitted elsewhere in the Code.

a. 14 AWG / 12 AWG 310.3(A)

Which of the following tables provides the allowable ampacities of insulated conductors rated up to and including 2,000 volts, 60°C through 90°C, where not more than three current-carrying conductors are installed in a raceway, cable, or earth (directly buried) based on an ambient temperature of 86°F?

a. 310.16

Conductors used for direct burial applications are required to be a type identified for such use.

a. True 310.10(E)

Where run in parallel in separate cables or raceways, the cables or raceways with conductors are required to have the same number of conductors and shall have the same electrical characteristics.

a. True 310.10(G)(3)

Where run in parallel, conductors of one phase, polarity, neutral, grounded circuit conductor, or equipment grounding conductor are required to have the same physical characteristics as those of another phase, polarity, neutral, grounded circuit conductor, or equipment grounding conductor.

a. True 310.10(G)(3)

Ampacities for conductors rated 0 to 2,000 volts are permitted to be determined by tables, as provided in 310.15, or under engineering supervision, as provided in 310.14(B).

a. True 310.14(A)(1)

Ampacities for conductors rated 0 to 2,000 volts are to be as specified in the Allowable Ampacity Table 310.16 through Table 310.21 as modified by 310.15(A) through (F).The temperature correction and adjustment factors shall be permitted to be applied to the ampacity for the temperature rating of the conductor if the corrected and adjusted ampacity does not exceed the ampacity for the temperature rating of the termination in accordance with the provisions of 110.14(C

a. True 310.15(A)

Where bare or covered conductors rated 0 to 2,000 volts are installed with insulated conductors, the temperature rating of the bare or covered conductor shall be equal to the lowest temperature rating of the insulated conductors for the purpose of determining ampacity.

a. True 310.15(D)

In a 3-wire circuit consisting of two phase conductors and the neutral conductor of a 4-wire, 3-phase, wye-connected system, a common conductor carries approximately the same current as the line-to-neutral load currents of the other conductors and shall be counted when applying the provisions of NEC 310.15(C)(1) where the conductors are rated 0 to 2,000 volts.

a. True 310.15(E)(2)

On a 4-wire, 3-phase wye circuit where the major portion of the load consists of nonlinear loads, the neutral conductor shall be considered a current-carrying conductor where the conductors are rated 0 to 2,000 volts.

a. True 310.15(E)(3)

When insulated conductors or cables are used where exposed to direct rays of the sun, they must be listed, or listed and marked, as being sunlight resistant or be covered with insulating material, such as tape or sleeving, that is listed, or listed and marked, as being sunlight resistant.

a. True REF: 310.10(D)

The trade name for type letter THHN is ? .

a. heat-resistant thermoplastic

Ampacities for conductors rated 2,001 to 35,000 volts are required to be as specified in Table 311.60(C)(67) through Table 311.60(C)(86). Ampacities for ambient temperatures other than those specified in these ampacity tables shall be corrected in accordance with which one of the following NEC references?

b. 311.60(D)(4) 311.60(C)

The maximum operating temperature of type letter UF with moisture-resistant insulation is ? .

b. 60°C

Where raceways or cables are exposed to direct sunlight on or above rooftops, raceways or cables installed a minimum of ? above the roof to the bottom of the raceway or cable do not require the 33°C adder to determine the applicable ambient temperature.

b. 7/8" 310.15(B)(2)

Where installed in raceways, conductors ? and larger, when not specifically permitted or required elsewhere in the NEC to be solid, are required to be stranded.

b. 8 AWG 310.3(C)

The insulation thickness of 2/0 AWG Type USE cable is ? .

b. 80 mils

The scope of Article 310 covers fixture wires, flexible cords, and cables.

b. False 310.1

Where more than one ampacity applies for a given circuit length for conductors rated 0 to 2,000 volts, the highest value is generally required to be used.

b. False 310.14(A)(2)

A neutral conductor rated 0 to 2,000 volts that carries only the unbalanced current from other conductors of the same circuit shall be required to be counted when applying the provisions of NEC 310.15(C)(1).

b. False 310.15(E)(1)

Type THHW has a maximum operating temperature of 75°C in a wet location, and ? in a dry location.

c. 90°C

Where the number of current-carrying conductors in a raceway or cable exceeds three, or where single conductors or multiconductor cables are installed without maintaining spacing for a continuous length longer than 24 inches and are not installed in raceways, the allowable ampacity of each conductor shall be reduced as shown in which of the following, when the conductors are rated 0 to 2,000 volts?

c. Table 310.15(C)(1

Insulated conductors and cables used in wet locations must comply with which of the following?

d. Any of the above 310.10(C)

Ampacities for conductors rated 0 to 2,000 volts in ambient temperatures other than those shown in the ampacity tables shall be corrected in accordance with which of the following?

d. Either a. or b.

Which of the following applies to conductors in each phase, polarity, neutral, grounded circuit conductor, equipment grounding conductor, or equipment bonding jumper where conductors are run in parallel?

f. Must be all of the above 310.10(G)(2)