Electrician Wiring Methods and Materials 2 — Questions and Answers
Question 1: What is EMT commonly called in the field?
- Rigid conduit
- Thin-wall conduit (Correct answer)
- Flex conduit
- Liquid-tight conduit
Correct answer: Thin-wall conduit
EMT (Electrical Metallic Tubing) is commonly called thin-wall conduit due to its lighter wall thickness compared to RMC.
Question 2: What is the purpose of a conduit body (LB, LL, LR)?
- To splice conductors
- To change direction and provide access to conductors (Correct answer)
- To protect conductors from water
- To ground the conduit system
Correct answer: To change direction and provide access to conductors
Conduit bodies are used to change the direction of a conduit run and provide access to conductors for pulling and maintenance.
Question 3: How is armored cable (Type AC) different from metal-clad cable (Type MC)?
- AC has an aluminum bonding strip; MC does not
- AC uses aluminum wire; MC uses copper
- MC has an aluminum bonding strip; AC uses an internal bare wire that provides fault return (Correct answer)
- They are identical
Correct answer: MC has an aluminum bonding strip; AC uses an internal bare wire that provides fault return
Type MC cable contains an insulated equipment grounding conductor, while Type AC relies on an aluminum bonding strip inside the armor for fault current return.
Question 4: What is the minimum bending radius for 1-inch EMT?
- 4 inches
- 5 inches
- 6 inches (Correct answer)
- 8 inches
Correct answer: 6 inches
The NEC requires a minimum bending radius of 6 times the internal diameter for EMT to prevent conductor damage.
Question 5: Which wiring method is specifically designed for use in wet or damp locations exposed to weather?
- NM cable
- UF cable (Correct answer)
- AC cable
- FMC
Correct answer: UF cable
Underground feeder (UF) cable is designed for direct burial and wet or damp locations, unlike standard NM cable.
Question 6: What is the maximum number of 90-degree bends allowed in a single conduit run between pull points?
- 2
- 3
- 4 (Correct answer)
- 6
Correct answer: 4
The NEC limits conduit runs to a maximum of 360 degrees of total bends (equivalent to four 90-degree bends) between pull points.
Electrician Wiring Methods and Materials 2
What is EMT commonly called in the field?