E2 Wiring Methods and Materials 2

Question 1

What is the maximum number of 90-degree bends permitted in a single run of EMT between pull points?

Accepted Answer

Four 90-degree bends

Answer

NEC 358.26 limits EMT to a maximum of four quarter bends (360 degrees total) between pull points.

Question 2

Which wiring method is specifically listed for use in concrete encasement?

Accepted Answer

Rigid Metal Conduit (RMC)

Answer

RMC (Rigid Metal Conduit) is permitted for direct burial and encasement in concrete per NEC 344.10.

Question 3

Under NEC Article 330, Metal-Clad (MC) cable installed exposed in a commercial building must be supported at intervals not exceeding:

Accepted Answer

6 feet

Answer

NEC 330.30 requires MC cable to be secured and supported at intervals not exceeding 6 feet.

Question 4

When installing liquidtight flexible metal conduit (LFMC) in lengths exceeding 6 feet, the installer must:

Accepted Answer

Use a separate equipment grounding conductor inside

Answer

Per NEC 350.60, LFMC in lengths over 6 feet is not permitted to serve as the sole equipment grounding path — a separate EGC is required.

Question 5

What is the minimum cover requirement for RMC installed directly in a concrete slab on grade?

Accepted Answer

0 inches — no cover required

Answer

NEC Table 300.5 requires no additional cover for RMC encased in concrete above grade.

(E2) E2 Commercial Electrical Inspector Practice Test