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NEC 2017 Code Changes in Wiring Methods and Materials


Quiz Questions

1.Electrical metallic tubing (EMT)
was added as an acceptable wiring method to afford protection from physical damage for conductors installed underground and subject to physical damage.
Was denied as an acceptable method for underground wiring.
2. Raceways or cables installed on rooftops are now required to be installed
23 mm (7/8 in.) above the rooftop to avoid a temperature adder of 33°C (60°F).
48 mm ( 1 5/8) above the rooftop to avoid a temperature adder of 33°C (60°F).
3. 312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures. Conductors entering enclosures within the scope of this article shall be protected from abrasion and shall comply with 312.5(A) through (C).
NEC 2017 Code Changes in Wiring Methods and Materials 1
True
False
4. Power monitoring equipment is
NEC 2017 Code Changes in Wiring Methods and Materials 2
not required to be listed for the application when installed in free spaces of cabinets and cutout boxes
now required to be listed for the application when installed in free spaces of cabinets and cutout boxes
5. New text was added to accommodate boxes with internal barriers for box volume and box fill calculations.
NEC 2017 Code Changes in Wiring Methods and Materials 3
True
False
6. The outside sheath of Type NM or Type UF cable used with a metal box must now extend not less than
6 mm (1/4 in.) inside the box as currently required for nonmetallic boxes.
12 mm (1/2 in.) inside the box as currently required for nonmetallic boxes.
3 mm (1/8 in.) inside the box as currently required for nonmetallic boxes.
7.Armored Cable-type wiring methods and associated fittings
are not required to be listed.
are required to be listed.
8. Type FCC cable
NEC 2017 Code Changes in Wiring Methods and Materials 4
will now be permitted in administrative office areas of hospitals and school buildings.
will not be permitted in administrative office areas of hospitals and school buildings.
9. Type TC-ER cable with a designation of "JP"
NEC 2017 Code Changes in Wiring Methods and Materials 5
will now be allowed to be installed without a raceway at dwelling units.
will not be allowed to be installed without a raceway at dwelling units.
10. Stainless steel RMC must be used only with stainless steel fittings, approved accessories, outlet boxes, and enclosures.
NEC 2017 Code Changes in Wiring Methods and Materials 6
True
False
11. Conductors Connected in Parallel. Where single conductor cables comprising each phase, neutral, or grounded conductor of an alternating-current circuit are connected in parallel as permitted in 310.10(H), the conductors shall be installed in groups consisting of not more than one conductor per phase, neutral, or grounded conductor to prevent current imbalance in the paralleled conductors due to inductive reactance
NEC 2017 Code Changes in Wiring Methods and Materials 7
True
False
12.Ampacity of Cables Rated 2000 Volts or Less. In cablebus that terminates at equipment with conductor temperature limitations, the allowable ampacity of single-conductor cables shall be as permitted by 310.15(A)(2). The adjustment factors of 310.15(B)(3) (a) shall not apply to the ampacity of cables in cablebus. The ampacity of single-conductor cables, nominally rated 2000 volts or less, shall comply with the following:

  1. The ampacities for 600 kcmil and larger single conductor cables in ventilated cablebus shall not exceed 75 percent of the allowable ampacities in Table 310.15(B)(17) and Table 310.15(B)(19).
  2. Where cablebus are continuously covered for more than 1.8 m (6 ft) with solid unventilated covers, the ampacities for 600 kcmil and larger cables shall not exceed 70 percent of the allowable ampacities in Table 310.15(B)(17) and Table 310.15(B)(19).
  3. The ampacities for 1/0 AWG through 500 kcmil single conductor cables in ventilated cablebus shall not exceed 65 percent of the allowable ampacities in Table 310.15(B)(17) and Table 310.15(B)(19).
  4. Where cablebus are continuously covered for more than 1.8 m (6 ft) with solid unventilated covers, the ampacities for 1/0 AWG through 500 kcmil cables shall not exceed 60 percent of the allowable ampacities in Table 310.15(B)(17) and Table 310.15(B)(19).
    NEC 2017 Code Changes in Wiring Methods and Materials 8
True
False