Wiring Methods and Protection Flashcards

When conductors of different systems share a raceway, what is the primary NEC requirement per 300.3(C)?

Answer: All conductors must be insulated for the highest voltage present

NEC 300.3(C)(1) requires that all conductors share insulation rated for the highest voltage present when they occupy the same raceway.

What is the minimum radius of the inner edge of a bend in ¾-inch EMT per NEC Table 344.24?

Answer: 10 inches

NEC Table 344.24 specifies a 10-inch minimum bend radius for ¾-inch EMT to prevent conductor insulation damage.

Which of the following wiring methods is approved for use in a Class I, Division 1 hazardous location?

Answer: Type MC-HL cable

Type MC-HL (Hazardous Location) cable is specifically listed for Class I, Division 1 locations per NEC 501.10.

Per NEC 358.30, EMT must be securely fastened within how many inches of each outlet box, junction box, or cabinet?

Answer: 24 inches

NEC 358.30(A) requires EMT to be secured within 24 inches of each outlet box, junction box, cabinet, or fitting.

What protection is required for NM cable passing through a 2×4 stud less than 1¼ inches from the edge of the stud?

Answer: A listed steel plate at least 1/16 inch thick

NEC 300.4(A)(1) requires a steel plate at least 1/16 inch thick when NM cable is within 1¼ inches of the edge of framing members.

Liquidtight flexible metallic conduit (LFMC) is permitted for outdoor use in which scenario?

Answer: Only when listed for outdoor use and protected from sunlight

LFMC is permitted outdoors when listed for that use, but must be protected from direct sunlight unless listed as sunlight-resistant per NEC 350.12.

What is the NEC requirement for sealing conduits entering a service entrance panel from underground?

Answer: The conduit must be sealed to prevent entry of gases or moisture

NEC 230.8 requires raceways entering buildings from underground to be sealed or plugged to prevent gas or moisture from entering the service equipment.