NFPA 70 NATIONAL ELECTRICAL CODE (NEC)
PRACTICE EXAMINATION | COMPREHENSIVE TEST
BANK WITH VERIFIED ANSWERS & DETAILED
RATIONALES | IDEAL FOR ELECTRICAL
ENGINEERING, ELECTRICAL TECHNOLOGY,
CONSTRUCTION MANAGEMENT & ELECTRICIAN
LICENSING CANDIDATES (2026–2027 EDITION)
1. According to the NEC, the primary purpose of the Code is the practical
safeguarding of:
a) Property and equipment only
b) Persons and property from electrical hazards
c) Utility company infrastructure
d) Electrical efficiency
b) Persons and property from electrical hazards
Rationale: NEC 90.1(A) states that the purpose of the Code is the practical
safeguarding of persons and property from hazards arising from the use of
electricity.
2. An appliance rated at 1,200 watts and 120 volts draws a current of:
a) 0.1 amperes
b) 10 amperes
c) 12 amperes
d) 1.2 amperes
b) 10 amperes
Rationale: Using Ohm's Law, Current = Power / Voltage = 1,200W / 120V =
10 amperes.
3. The minimum depth for a direct-burial cable without GFCI protection for a
20-ampere, 120-volt branch circuit supplying a dwelling unit is:
a) 6 inches
, b) 12 inches
c) 18 inches
d) 24 inches
d) 24 inches
Rationale: Table 300.5 requires a minimum cover of 24 inches for direct-
burial cables for residential branch circuits rated 120 volts or less with GFCI
protection and maximum overcurrent protection of 20 amperes; without
GFCI, other requirements may apply but 24 inches is standard. Actually, for
dwelling unit outdoor branch circuits 120V, 20A or less with GFCI, direct
burial is 12 inches per Column 4. Without GFCI, it's 24 inches? The question
says "without GFCI protection", so it's 24 inches. Good.
4. A "qualified person" as defined by the NEC is one who:
a) Has a college degree in electrical engineering
b) Has skills and knowledge related to the construction and operation of
electrical equipment and installations and has received safety training to
identify and avoid hazards
c) Is licensed as a professional engineer
d) Has at least 10 years of experience
b) Has skills and knowledge related to the construction and operation of
electrical equipment and installations and has received safety training to
identify and avoid hazards
Rationale: NEC Article 100 defines a qualified person as one who has been
trained to recognize and avoid electrical hazards.
5. The rating of a branch circuit overcurrent protective device shall not exceed
the ampacity of the conductors after applying any applicable:
a) Adjustment and correction factors
b) Voltage drop calculations
c) Conductor insulation type
d) Ambient temperature only
a) Adjustment and correction factors
Rationale: NEC 210.19(A)(1) requires conductors to have an ampacity not
, less than the maximum load to be served after applying adjustment and
correction factors.
6. The minimum size grounding electrode conductor for a service with 2/0
AWG copper service-entrance conductors is:
a) 8 AWG copper
b) 6 AWG copper
c) 4 AWG copper
d) 2 AWG copper
c) 4 AWG copper
Rationale: Table 250.66 specifies that for copper service-entrance
conductors size 2/0 or 3/0, the grounding electrode conductor (copper) must
be 4 AWG.
7. A receptacle installed in a dwelling unit bathroom must be:
a) GFCI protected
b) AFCI protected
c) On a dedicated circuit
d) 20-ampere rated only
a) GFCI protected
Rationale: NEC 210.8(A)(1) requires all 125-volt through 250-volt
receptacles in bathrooms to have ground-fault circuit-interrupter protection
for personnel.
8. The maximum number of disconnects allowed for a service entrance is:
a) One
b) Up to six
c) Up to eight
d) Unlimited
b) Up to six
Rationale: NEC 230.71(A) permits up to six switches or circuit breakers
grouped together to serve as the service disconnecting means.
9. A wet location is defined as:
a) An area subject to occasional dampness
, b) An interior location subject to saturation with water or other liquids
c) An area unprotected from weather
d) An underground location or one in concrete slabs or masonry in direct
contact with the earth
d) An underground location or one in concrete slabs or masonry in direct
contact with the earth
Rationale: NEC Article 100 defines a wet location as installations
underground or in concrete slabs or masonry in direct contact with the
earth; in locations subject to saturation with water or other liquids, such as
vehicle washing areas; and in unprotected locations exposed to weather.
10.The ampacity of a 12 AWG THHN copper conductor (75°C column) is:
a) 15 amperes
b) 20 amperes
c) 25 amperes
d) 30 amperes
c) 25 amperes
Rationale: Table 310.16 shows 12 AWG copper THHN in the 75°C column as
25 amperes. However, the typical overcurrent protection limit for 12 AWG is
20A for branch circuits per 240.4(D), but the ampacity is 25A.
11.All 125-volt, single-phase, 15- and 20-ampere receptacles in a dwelling unit
garage must be:
a) Tamper-resistant
b) Weather-resistant
c) GFCI protected
d) Both GFCI protected and tamper-resistant
c) GFCI protected
Rationale: NEC 210.8(A)(2) requires GFCI protection for receptacles in
garages. Tamper-resistant is required in certain areas per 406.12, but not all
garage receptacles must be tamper-resistant unless they are readily
accessible and meet the specific location requirements. So GFCI is the
primary requirement.
PRACTICE EXAMINATION | COMPREHENSIVE TEST
BANK WITH VERIFIED ANSWERS & DETAILED
RATIONALES | IDEAL FOR ELECTRICAL
ENGINEERING, ELECTRICAL TECHNOLOGY,
CONSTRUCTION MANAGEMENT & ELECTRICIAN
LICENSING CANDIDATES (2026–2027 EDITION)
1. According to the NEC, the primary purpose of the Code is the practical
safeguarding of:
a) Property and equipment only
b) Persons and property from electrical hazards
c) Utility company infrastructure
d) Electrical efficiency
b) Persons and property from electrical hazards
Rationale: NEC 90.1(A) states that the purpose of the Code is the practical
safeguarding of persons and property from hazards arising from the use of
electricity.
2. An appliance rated at 1,200 watts and 120 volts draws a current of:
a) 0.1 amperes
b) 10 amperes
c) 12 amperes
d) 1.2 amperes
b) 10 amperes
Rationale: Using Ohm's Law, Current = Power / Voltage = 1,200W / 120V =
10 amperes.
3. The minimum depth for a direct-burial cable without GFCI protection for a
20-ampere, 120-volt branch circuit supplying a dwelling unit is:
a) 6 inches
, b) 12 inches
c) 18 inches
d) 24 inches
d) 24 inches
Rationale: Table 300.5 requires a minimum cover of 24 inches for direct-
burial cables for residential branch circuits rated 120 volts or less with GFCI
protection and maximum overcurrent protection of 20 amperes; without
GFCI, other requirements may apply but 24 inches is standard. Actually, for
dwelling unit outdoor branch circuits 120V, 20A or less with GFCI, direct
burial is 12 inches per Column 4. Without GFCI, it's 24 inches? The question
says "without GFCI protection", so it's 24 inches. Good.
4. A "qualified person" as defined by the NEC is one who:
a) Has a college degree in electrical engineering
b) Has skills and knowledge related to the construction and operation of
electrical equipment and installations and has received safety training to
identify and avoid hazards
c) Is licensed as a professional engineer
d) Has at least 10 years of experience
b) Has skills and knowledge related to the construction and operation of
electrical equipment and installations and has received safety training to
identify and avoid hazards
Rationale: NEC Article 100 defines a qualified person as one who has been
trained to recognize and avoid electrical hazards.
5. The rating of a branch circuit overcurrent protective device shall not exceed
the ampacity of the conductors after applying any applicable:
a) Adjustment and correction factors
b) Voltage drop calculations
c) Conductor insulation type
d) Ambient temperature only
a) Adjustment and correction factors
Rationale: NEC 210.19(A)(1) requires conductors to have an ampacity not
, less than the maximum load to be served after applying adjustment and
correction factors.
6. The minimum size grounding electrode conductor for a service with 2/0
AWG copper service-entrance conductors is:
a) 8 AWG copper
b) 6 AWG copper
c) 4 AWG copper
d) 2 AWG copper
c) 4 AWG copper
Rationale: Table 250.66 specifies that for copper service-entrance
conductors size 2/0 or 3/0, the grounding electrode conductor (copper) must
be 4 AWG.
7. A receptacle installed in a dwelling unit bathroom must be:
a) GFCI protected
b) AFCI protected
c) On a dedicated circuit
d) 20-ampere rated only
a) GFCI protected
Rationale: NEC 210.8(A)(1) requires all 125-volt through 250-volt
receptacles in bathrooms to have ground-fault circuit-interrupter protection
for personnel.
8. The maximum number of disconnects allowed for a service entrance is:
a) One
b) Up to six
c) Up to eight
d) Unlimited
b) Up to six
Rationale: NEC 230.71(A) permits up to six switches or circuit breakers
grouped together to serve as the service disconnecting means.
9. A wet location is defined as:
a) An area subject to occasional dampness
, b) An interior location subject to saturation with water or other liquids
c) An area unprotected from weather
d) An underground location or one in concrete slabs or masonry in direct
contact with the earth
d) An underground location or one in concrete slabs or masonry in direct
contact with the earth
Rationale: NEC Article 100 defines a wet location as installations
underground or in concrete slabs or masonry in direct contact with the
earth; in locations subject to saturation with water or other liquids, such as
vehicle washing areas; and in unprotected locations exposed to weather.
10.The ampacity of a 12 AWG THHN copper conductor (75°C column) is:
a) 15 amperes
b) 20 amperes
c) 25 amperes
d) 30 amperes
c) 25 amperes
Rationale: Table 310.16 shows 12 AWG copper THHN in the 75°C column as
25 amperes. However, the typical overcurrent protection limit for 12 AWG is
20A for branch circuits per 240.4(D), but the ampacity is 25A.
11.All 125-volt, single-phase, 15- and 20-ampere receptacles in a dwelling unit
garage must be:
a) Tamper-resistant
b) Weather-resistant
c) GFCI protected
d) Both GFCI protected and tamper-resistant
c) GFCI protected
Rationale: NEC 210.8(A)(2) requires GFCI protection for receptacles in
garages. Tamper-resistant is required in certain areas per 406.12, but not all
garage receptacles must be tamper-resistant unless they are readily
accessible and meet the specific location requirements. So GFCI is the
primary requirement.
