G17 Journeyman Electrician Exam
- Which color is typically used to identify the grounded (neutral) conductor in residential
wiring according to the NEC?
- Red
- White
- Green
- Black
Answer: B) White
Explanation: The National Electrical Code (NEC) designates the white (or gray) conductor as the grounded (neutral) conductor to distinguish it from ungrounded (hot) and grounding conductors.
- When working on an energized circuit, what is the most critical first step to ensure safety?
- Wear non-conductive footwear
- Turn off and lockout/tagout the power source if possible
- Use a wooden ladder
- Check circuit voltage after completing the work
Answer: B) Turn off and lockout/tagout the power source if possible 1 / 4
G17 Journeyman Electrician Exam
Explanation: Lockout/tagout procedures are crucial for ensuring no unexpected energization, preventing electrical shocks and accidents.
- According to OSHA and NFPA 70E standards, which class of Personal Protective Equipment
(PPE) is primarily used for arc flash protection?
- Class G gloves
- Arc-rated clothing
- Leather work boots
- Safety glasses only
Answer: B) Arc-rated clothing
Explanation: NFPA 70E mandates arc-rated clothing in environments where arc flash hazards exist to protect workers from intense heat and blasts.
- In a lockout/tagout (LOTO) procedure, the tag primarily serves what purpose?
- To lock the breaker in the off position
- To provide a written warning that the circuit is under lockout
- To supply an alternative way to turn on the circuit
- To identify the load side of the circuit 2 / 4
G17 Journeyman Electrician Exam
Answer: B) To provide a written warning that the circuit is under lockout
Explanation: While the lock physically prevents re-energizing equipment, the tag communicates who locked it out and why, warning others not to remove it.
- Which of the following best describes a ground fault?
- A short circuit between two hot conductors
- A connection between an ungrounded conductor and a grounded surface
- A breaker that trips due to overload
- A conductor that is too large for its circuit
Answer: B) A connection between an ungrounded conductor and a grounded surface
Explanation: Ground faults occur when current unintentionally flows from a hot conductor to ground, causing excessive current and potentially tripping protective devices.
- What is the primary purpose of grounding a circuit or electrical system?
- To reduce voltage drop
- To provide a reference voltage for instrumentation
- To ensure a low-resistance path for fault current 3 / 4
G17 Journeyman Electrician Exam
- To increase conductor insulation
Answer: C) To ensure a low-resistance path for fault current
Explanation: Grounding limits the voltage to ground on electrical systems and provides a path for fault current to facilitate overcurrent device operation.
- When a circuit breaker is rated for 20A, what is the maximum continuous load typically
permitted on that circuit under the NEC?
A) 10A
B) 16A
C) 20A
D) 25A
Answer: B) 16A
Explanation: For continuous loads (three hours or more), the NEC generally requires derating to 80% of a circuit breaker’s rating. Thus, 80% of 20A is 16A.
- Which test instrument is best suited for measuring high levels of current in a conductor
without disconnecting it?
- Multimeter with test leads
- / 4