Wiring Methods and Materials Flashcards
7 cards from real Licensed Electrical Contractor practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Wiring Methods and Materials flashcards as text
What is the maximum number of 90-degree bends permitted in a single run of rigid metal conduit (RMC) between pull points?
Answer: Four 90-degree bends
NEC 358.26 and 344.26 limit conduit runs to the equivalent of four quarter bends (360 total degrees) between pull points, outlets, or junction boxes.
Which wiring method is permitted for use in a Class I, Division 1 hazardous location?
Answer: Rigid metal conduit (RMC)
NEC Article 501 requires threaded rigid metal conduit or Type MI cable in Class I, Division 1 hazardous locations.
When installing Type UF cable underground, what is the minimum burial depth required for a residential branch circuit rated at 120 volts?
Answer: 18 inches
NEC Table 300.5 requires Type UF cable to be buried a minimum of 24 inches, but under a dwelling unit the depth is 18 inches.
Electrical metallic tubing (EMT) is NOT permitted to be used in which of the following locations?
Answer: Concrete encasement in wet locations
NEC 358.10 prohibits EMT where subject to severe physical damage or where embedded in concrete in wet locations; RMC or IMC is required instead.
What is the minimum size of equipment grounding conductor required for a circuit protected by a 60-ampere overcurrent device using copper conductors?
Answer: 10 AWG
Per NEC Table 250.122, a 60-ampere overcurrent device requires a minimum 10 AWG copper equipment grounding conductor.
Type MC cable installed in a cable tray must be secured at intervals not exceeding how many feet?
Answer: 6 feet
NEC 330.30 requires Type MC cable to be secured at intervals not exceeding 6 feet when run horizontally in a cable tray.
Which of the following conductors is approved for direct burial without conduit?
Answer: Type UF
Type UF (Underground Feeder) cable is specifically listed for direct burial per NEC 340.10.