UNEC 310

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The ________ rating of a conductor is the maximum temperature, at any location along its length, which the conductor can withstand over a prolonged period of time without serious degradation. a. ambient b. temperature c. maximum withstand d. short-circuit

Temperature

Conductors shall be permitted for use in any of the wiring methods recognized in Chapter 3 and as permitted in the NEC. True or False

True

Each current-carrying conductor of a paralleled set of conductors shall be counted as a current-carrying conductor for the purpose of applying the adjustment factors of 310.15(B) (3) (a). True or False

True

No conductor shall be used where its operating temperature exceeds that designated for the type of insulated conductor involved. True or False

True

On a three-phase, 4-wire, wye circuit, where the major portion of he load consists of nonlinear loads, the neutral conductor shall be counted when applying 310.15(B)(3)(a) adjustment factors. True or False

True

The service or feeder ratings addressed by 310.15(B)(7) are based on the standard ampacity ratings from 240.6(A) True or False

True

When determining the number of current-carrying conductors, a grounding or bonding conductor shall not be counted when applying the provision of 310.15(B)(3)(a). True or False

True

Where conductors in parallel are run in separate raceways, the raceways shall have the same electrical characteristics. True or False

True

The minimum size copper conductor permitted for branch circuits under 600V is__________ AWG. a. 14 b. 12 c. 10 d. 8

a. 14

A(n)_______conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to be counted when applying the provisions of 310.15(B)(3)(a). a. neutral b. ungrounded c. grounding d. none of these

a. neutral

For one-family dwellings and the individual dwelling units of two-family and multifamily dwellings, single-phase feeder conductors consisting of ________ ungrounded conductor(s) and the neutral conductor from a 208Y/120 volt system shall be permitted to be sized in accordance with 310.15(B)(7)(1) through (3). a. 1 b. 2 c. 3 d. 4

b. 2

Conductor adjustment factors shall not apply to conductors in raceways having a length not exceeding _____ in. a. 12 b. 24 c. 36 d. 48

b. 24

Where installed in raceways, conductors __________ AWG and larger shall be stranded, unless specifically permitted or required elsewhere in the NEC. a. 10 b. 8 c. 6 d. 4

b. 8

Type_______insulated conductors shall not be subject to the ampacity adjustment provisions of 310.15(B)(3)(c). a. THW-2 b. XHHW-2 c. THWN-2 d. RHW-2

b. XHHW-2

The ampacities listed in 310.15 do not take ________ into consideration. a. continuous loads b. voltage drop c. insulation d. wet locations

b. voltage drop

Where six current-carrying conductors are run in the same conduit or cable, the ampacity of each conductor shall be lowered to _______ percent of its ampacity. a. 40 b. 60 c. 80 d. 90

c. 80 ??? look for the answer

There are four principal determinants of conductor operating temperature, one of which is __________generated internally in the conductor as the result of load current flow, including fundamental and harmonic currents. a. friction b. magnetism c. heat d. none of these

c. heat

In general, the minimum size conductor permitted for use in parallel installations is _______AWG. a. 10 b. 4 c. 1 d. 1/0

d. 1/0

Sectioned equipment grounding conductors smaller than ________ AWG shall be permitted in multiconductor cables, if the combines circular mil area of the sectioned equipment grounding conductors in each cable complies with 250.122. a. 3 b. 2 c. 1 d. 1/0

d. 1/0

If cables meeting the requirements in 310.15(B)(3)(4)a through c with more than 20 current-carrying conductors are installed longer than 24 in. without maintaining spacing, are stacked, or are supported on bridle rings, a _______ percent adjustment factor shall be applied. a. 30 b. 40 c. 50 d. 60

d. 60

Where conductors are installed in raceways or cables exposed to direct sunlight on or above rooftops, a temperature adder of _____ Fahrenheit shall be added to the outdoor temperature where the conduits are less than 7/8 in. from the rooftop. a. 30 b. 40 c. 50 d. 60

d. 60

Where raceways or cables are exposed to direct sunlight on or above rooftops, raceways or cables shall be installed a minimum distance of ______in. above the roof to the bottom of the raceway or cable. a. 1/4 b. 1/3 c. 1/2 d. 7/8

d. 7/8

Conductors smaller than 1/0 AWG can be connected in parallel to supply control power, provided_________. a. they are all contain within the same raceway or cable b. each parallel conductor has an ampacity sufficient to carry the entire load c. the circuit overcurrent device rating does not exceed the ampacity of any individual parallel conductor d. all of these

d. all of these

Parallel conductors shall have the same___________. a. length b. material c. size in circular mil area d. all of these

d. all of these

The ampacity adjustment factors of Table 310.15(B)(3)(a) do not apply to Type AC or Type MC cable without an overall outer jacket, if which of the following condition(s) is (are) met? a. each cable has not more than three current-carrying conductors. b. the conductors are 12 AWG copper. c. no more than 20 current-carrying conductors are installed without maintaining spacing. d. all of these

d. all of these

Where correction or adjustment factors are required by 310.15(B)(2) or (3), for single-phase feeder conductors installed for _______ dwellings, they shall be permitted to be applied to the ampacity associated with the temperature rating of the conductor. a. one-family b. the individual dwelling units of two-family c. the individual dwelling units of multifamily d. all of these

d. all of these

Insulated conductors used in wet locations shall be _________. a. moisture-impervious metal-sheathed b. MTW, RHW, RHW-2, TW, THW, THW-2, THHW, THWN, THWN-2, or ZW c. listed for wet locations d. any of these

d. any of these

When bare conductors are installed with insulated conductors, their ampacities shall be limited to _________. a. 60 degrees in Celsius b. 75 degrees in Celsius c. 90 degrees in Celsius d. the lowest temperature rating for any of the insulated conductors

d. the lowest temperature rating for any of the insulated conductors.


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