Wiring Methods Flashcards

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 limits the total bends to 360 degrees (equivalent to four 90-degree bends) between pull points in EMT and RMC runs.

Which wiring method is specifically listed for use in hazardous (classified) locations Class I, Division 1?

Answer: Rigid metal conduit (RMC)

Rigid metal conduit (RMC) is one of the approved wiring methods for Class I, Division 1 hazardous locations per NEC Article 501.

When installing PVC conduit underground, what is the minimum cover required for a branch circuit rated 120V or less under a residential driveway?

Answer: 18 inches

NEC Table 300.5 requires 18 inches of cover for PVC conduit under residential driveways for circuits 120V or less.

What is the minimum radius for a field bend in 2-inch RMC?

Answer: 9.5 inches

NEC Table 344.24 specifies a minimum bend radius of 9.5 inches for 2-inch RMC to prevent conductor damage.

Type UF cable differs from Type NM cable primarily because UF cable is:

Answer: Suitable for direct burial in the earth

Type UF (Underground Feeder) cable has a moisture-resistant, sunlight-resistant jacket approved for direct burial per NEC 340.10.

Which of the following conduit types is NOT permitted to be used as an equipment grounding conductor?

Answer: Rigid polyvinyl chloride conduit (PVC)

PVC conduit is a non-metallic raceway and cannot serve as an equipment grounding conductor; a separate EGC must be installed.

When using flexible metal conduit (FMC) for a motor connection, what is the maximum length permitted without an additional equipment grounding conductor?

Answer: 6 feet

NEC 350.60 allows FMC up to 6 feet to serve as the EGC provided it meets the listed conditions, including a minimum trade size of ½ inch.