G18 Residential Electrician Exam
Question 1 Which section of the National Electrical Code primarily addresses residential wiring standards?
a) NEC Article 250
b) NEC Article 200
c) NEC Article 210
d) NEC Article 90
Answer: c) NEC Article 210
Explanation: NEC Article 210 covers branch circuits in residential installations, detailing required outlet spacing and other critical wiring standards.
Question 2 What is the main purpose of a ground fault circuit interrupter (GFCI)?
a) To regulate voltage drop in long circuits
b) To prevent fires caused by overheated wires
c) To protect against electrical shock from ground faults
d) To provide surge protection for sensitive devices
Answer: c) To protect against electrical shock from ground faults
Explanation: GFCIs monitor current imbalances between the hot and neutral conductors, rapidly disconnecting power if a ground fault is detected.
Question 3 1 / 4
G18 Residential Electrician Exam
According to the NEC, a dedicated 20A branch circuit for a kitchen countertop receptacle must not serve which of the following?
a) Refrigerator
b) Garbage disposal
c) Range hood
d) Dishwasher
Answer: d) Dishwasher
Explanation: Kitchen countertop small-appliance branch circuits cannot serve fixed appliances like dishwashers. These appliances typically require their own dedicated circuits.
Question 4 Which of the following best describes “bonding” in electrical systems?
a) Interconnecting all grounding electrodes
b) Ensuring a low-resistance path to the panel
c) Establishing a reliable conductive path to reduce shock risks
d) Installing a supplementary ground rod
Answer: c) Establishing a reliable conductive path to reduce shock risks
Explanation: Bonding is connecting metal parts together and to the grounding system to reduce potential differences and minimize electrical shock hazards.
Question 5 2 / 4
G18 Residential Electrician Exam
Which component is designed to protect against fires caused by arcing faults in residential circuits?
a) GFCI breaker
b) AFCI breaker
c) Dual-pole breaker
d) High-amperage breaker
Answer: b) AFCI breaker
Explanation: Arc-Fault Circuit Interrupter (AFCI) breakers detect and interrupt arcing faults that could lead to electrical fires.
Question 6 When working on a live circuit, which type of personal protective equipment is most crucial?
a) A dust mask
b) Thermal gloves
c) Insulated gloves
d) Earplugs
Answer: c) Insulated gloves
Explanation: Insulated gloves protect electricians from electric shock when working on or near live circuits.
Question 7 3 / 4
G18 Residential Electrician Exam
A key objective of lockout/tagout procedures is to
a) Label all branch circuits clearly
b) Prevent unauthorized use of electrical tools
c) Ensure circuit breakers do not trip accidentally
d) Prevent the accidental re-energization of equipment
Answer: d) Prevent the accidental re-energization of equipment
Explanation: Lockout/tagout procedures secure equipment in a de-energized state and warn others not to restore power prematurely.
Question 8 Which is the standard U.S. residential voltage for most branch circuits?
- 120/240 V single-phase
- 277/480 V three-phase
- 208/120 V three-phase
- 600 V single-phase
Answer: a) 120/240 V single-phase
Explanation: Typical U.S. residential electrical service is supplied as 120/240 V single-phase, providing both 120 V and 240 V for household loads.
Question 9 The minimum depth for a residential grounding electrode (ground rod) is typically
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