CEP CEP National Electrical Code (NEC) & Code Compliance 2 — Questions and Answers
Question 1: NEC Article 406 regulates receptacles, cord connectors, and attachment plugs. What is required when replacing a non-grounding-type receptacle in an older installation where no grounding means exists?
- Install a new grounding receptacle with a pigtail to the box
- Replace with another non-grounding receptacle or a GFCI receptacle (Correct answer)
- Install a new circuit from the panel
- Use an adapter plug
Correct answer: Replace with another non-grounding receptacle or a GFCI receptacle
NEC 406.4(D)(2) permits replacing a non-grounding receptacle with a GFCI-type and labeling it 'No Equipment Ground'.
Question 2: Under NEC 300.3(B), all conductors of the same circuit must be contained in the same raceway, cable, or trench primarily to:
- Reduce voltage drop
- Minimize inductive heating of ferrous metal enclosures (Correct answer)
- Comply with color-coding requirements
- Simplify circuit identification
Correct answer: Minimize inductive heating of ferrous metal enclosures
Grouping all circuit conductors together cancels the magnetic fields and prevents inductive heating in metal conduit or enclosures.
Question 3: NEC 110.26 specifies working space in front of electrical equipment. For a 480V panelboard with exposed live parts on one side, what is the minimum depth of working space (Condition 2)?
- 3 feet
- 3.5 feet
- 4 feet (Correct answer)
- 5 feet
Correct answer: 4 feet
NEC Table 110.26(A)(1) requires 4 feet of working clearance for 151–600V equipment under Condition 2 (grounded surfaces opposite live parts).
Question 4: Which NEC article specifically addresses wiring for health care facilities, including patient care areas?
- Article 500
- Article 517 (Correct answer)
- Article 520
- Article 530
Correct answer: Article 517
NEC Article 517 covers electrical installations in health care facilities, including essential electrical systems and patient care areas.
Question 5: Per NEC 314.28, what is the minimum inside dimension of a pull box installed on a straight pull of 3-inch conduit?
- 18 inches
- 24 inches (Correct answer)
- 27 inches
- 36 inches
Correct answer: 24 inches
NEC 314.28(A)(1) requires that for straight pulls the box length be at least eight times the trade size of the largest conduit, so 8 × 3 = 24 inches.
Question 6: According to NEC 240.4(D), small conductors of 14 AWG copper must be protected at a maximum overcurrent device rating of:
- 15 amperes (Correct answer)
- 20 amperes
- 25 amperes
- 30 amperes
Correct answer: 15 amperes
NEC 240.4(D)(3) limits the overcurrent protection for 14 AWG copper conductors to a maximum of 15 amperes.
CEP CEP National Electrical Code (NEC) & Code Compliance 2
NEC Article 406 regulates receptacles, cord connectors, and attachment plugs.
What is required when replacing a non-grounding-type receptacle in an older installation where no grounding means exists?