Journeyman Electrician’s Exam Journeyman Electrician's Boxes and Enclosures 2 — Questions and Answers
Question 1: According to NEC 314.28(A)(1), what is the minimum box length required for a straight pull when the largest raceway entering the box is 3-inch trade size?
- 18 inches
- 24 inches (Correct answer)
- 30 inches
- 36 inches
Correct answer: 24 inches
For straight pulls, the minimum length is 8 times the largest raceway trade size: 8 × 3 = 24 inches.
Question 2: Per NEC 314.28(A)(2), what multiplier is used to calculate the minimum box dimension for angle pulls or U-pulls?
- 4 times the largest raceway plus sum of remaining raceways
- 6 times the largest raceway plus sum of remaining raceways (Correct answer)
- 8 times the largest raceway plus sum of remaining raceways
- 10 times the largest raceway plus sum of remaining raceways
Correct answer: 6 times the largest raceway plus sum of remaining raceways
NEC 314.28(A)(2) requires angle and U-pulls to have a minimum dimension of 6 times the largest raceway plus the sum of any other raceways on the same wall.
Question 3: NEC 314.28 pull box sizing requirements apply when conductors are at least what size?
- 6 AWG or larger
- 4 AWG or larger (Correct answer)
- 2 AWG or larger
- 1/0 AWG or larger
Correct answer: 4 AWG or larger
NEC 314.28 applies to boxes used as junction or pull boxes for conductors 4 AWG or larger; smaller conductors fall under the box fill rules of 314.16.
Question 4: NEC 314.29 requires that junction boxes and pull boxes be:
- Installed only in accessible attics or crawl spaces
- Accessible without removing any part of the building structure or finish (Correct answer)
- Labeled with the voltage and ampacity of contained conductors
- Located within 6 feet of the equipment they serve
Correct answer: Accessible without removing any part of the building structure or finish
NEC 314.29 mandates that boxes be accessible without removing permanent building structures or finishes to allow future maintenance.
Question 5: Per NEC 314.16(C)(2), a conduit body used for splicing must:
- Never contain splices under any circumstances
- Have its volume marked and meet the conductor fill requirements of 314.16(B) (Correct answer)
- Be at least 4 inches in trade size to permit splicing
- Be listed as a junction box rather than a conduit body
Correct answer: Have its volume marked and meet the conductor fill requirements of 314.16(B)
NEC 314.16(C)(2) requires splicing conduit bodies to have their volume marked and to satisfy the conductor fill requirements of 314.16(B).
Question 6: A pull box has a 2-inch conduit and a 3-inch conduit entering the same wall for an angle pull. What is the minimum required dimension of that wall?
- 18 inches (6 × 3)
- 20 inches (6 × 3 + 2) (Correct answer)
- 24 inches (8 × 3)
- 30 inches (8 × 3 + 6)
Correct answer: 20 inches (6 × 3 + 2)
For angle pulls: 6 × largest raceway + sum of others = (6 × 3) + 2 = 18 + 2 = 20 inches minimum.
Question 7: According to NEC 314.28(A)(1), if a straight pull box has a 4-inch trade size conduit entering it, what is the minimum required box length?
- 24 inches
- 32 inches (Correct answer)
- 36 inches
- 48 inches
Correct answer: 32 inches
For straight pulls: 8 × largest raceway trade size = 8 × 4 = 32 inches minimum box length.
