NEC Wiring Methods & Materials 2

Question 1

What is the minimum burial depth for Type UF cable supplying a 120V outdoor receptacle not exceeding 20A?

Accepted Answer

12 inches

Answer

NEC Table 300.5 requires Type UF cable to be buried at least 12 inches deep for 120V circuits rated 20A or less.

Question 2

Which wiring method is permitted in a Class I, Division 1 hazardous location?

Accepted Answer

Threaded rigid metal conduit (RMC)

Answer

NEC 501.10(A) requires threaded rigid metal conduit (RMC) or threaded steel intermediate metal conduit (IMC) in Class I, Division 1 locations.

Question 3

When installing EMT, what is the maximum distance from a box or fitting that a support must be placed?

Accepted Answer

3 feet

Answer

NEC 358.30(A) requires EMT to be secured within 3 feet of every outlet box, junction box, cabinet, or fitting.

Question 4

What color is the equipment grounding conductor insulation typically required to be?

Accepted Answer

Green or bare

Answer

NEC 250.119 requires equipment grounding conductors to be identified by green insulation, green with one or more yellow stripes, or bare copper.

Question 5

What is the maximum number of quarter bends (360 degrees total) permitted in a single run of conduit between pull points?

Accepted Answer

360 degrees total

Answer

NEC 358.26 (for EMT) and similar sections for other conduit types limit bends to 360 degrees total between pull points.

NEC Practice Test