Journeyman Electrician Practice Test
Journeyman Electrician Wiring Methods & Materials Practice Questions
Wiring Methods & Materials makes up 8 of every 50 questions on a Tigertest Journeyman Electrician practice test. Here are 10 of the 32 questions on it, each with the answer and the reason.
Updated by the Tigertest team. Based on the 2023 National Electrical Code (NFPA 70) and standard electrical theory. Original questions; 50 per test, 70% to pass. State licensing law not included.
1. A cable run through a bored hole in a wood stud must be at least how far from the nearest edge, unless protected?
- A.3/4 in.
- B.1 1/4 in.
- C.1 in.
- D.1 1/2 in.
Answer: B. Holes bored for cables or raceways must be at least 1 1/4 in. from the nearest edge of the wood member. Otherwise a steel plate or sleeve protects the cable.
2. For an angle pull, the distance to the opposite wall must be at least six times the largest raceway plus:
- A.The conductor bending radius
- B.Six inches per conductor
- C.Twice the largest raceway
- D.The sum of the others in the row
Answer: D. For angle or U pulls, the distance is six times the trade size of the largest raceway in a row plus the sum of the trade sizes of the other raceways in that row on the same wall.
3. Cables installed under metal-corrugated sheet roof decking must be kept at least how far below the bottom of the decking?
- A.1 1/2 in.
- B.2 in.
- C.1 1/4 in.
- D.1 in.
Answer: A. Cables and raceways under metal roof decking must be at least 1 1/2 in. from the lowest surface of the decking to protect them from roofing screws.
4. What is the minimum cover for direct-burial cable in general locations, not under a building or slab?
- A.12 in.
- B.30 in.
- C.24 in.
- D.18 in.
Answer: C. The burial depth table requires 24 in. of cover for direct-burial cables or conductors in general locations. Smaller depths apply to raceways and to some residential circuits.
5. The final ampacity of NM cable conductors may not exceed the value in the:
- A.90°C column
- B.Termination rating
- C.60°C column
- D.75°C column
Answer: C. NM cable conductors have 90°C insulation, which may be used for adjustment and correction, but the final ampacity may not exceed the 60°C rating.
6. Maximum fill for three or more conductors in a conduit (not a short nipple) is:
- A.40 percent
- B.53 percent
- C.60 percent
- D.31 percent
Answer: A. Chapter 9, Table 1 allows 53 percent fill for one conductor, 31 percent for two, and 40 percent for more than two.
7. In Table 310.16, 6 AWG copper THWN at 75°C has an ampacity of:
- A.50 A
- B.55 A
- C.75 A
- D.65 A
Answer: D. 6 AWG copper is 55 A at 60°C, 65 A at 75°C and 75 A at 90°C. THWN is a 75°C insulation in wet and dry locations.
8. Where service conductors are buried 18 in. or more, a warning ribbon must be placed at least how far above them?
- A.24 in.
- B.12 in.
- C.6 in.
- D.18 in.
Answer: B. Underground service conductors not encased in concrete and buried 18 in. or more must have a warning ribbon in the trench at least 12 in. above the installation.
9. At each box, at least how much free conductor must be left for splices or device connections?
- A.12 in.
- B.6 in.
- C.3 in.
- D.8 in.
Answer: B. At least 6 in. of free conductor, measured from where it emerges from the raceway or cable, must be left at each outlet, junction and switch point.
10. In box fill, each yoke holding a device such as a switch or receptacle counts as:
- A.Three volumes
- B.No volume
- C.One volume
- D.Two volumes
Answer: D. Each device yoke counts as two conductor volumes based on the largest conductor connected to that device. A device wider than a single 2 in. box counts double for each gang.
Practice all 32 wiring methods & materials questions, and the rest of the 200-question bank, in the free Journeyman Electrician training sets. Questions you miss come back until you have mastered them.
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