NEC GROUNDING AND BONDING
EXAMINATION WITH ACTUAL QUESTIONS
AND VERIFIED ANSWERS, PLUS
EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. What is the primary purpose of the equipment grounding
conductor (EGC) in an electrical installation?
A. To carry the normal operating current of the circuit
B. To provide a low-impedance path for fault current back to the source
so the overcurrent protective device can operate
C. To stabilize the voltage between ungrounded conductors
D. To replace the grounded circuit conductor in a multiwire branch
circuit
Answer: B. To provide a low-impedance path for fault current back
to the source so the overcurrent protective device can operate
Rationale: The equipment grounding conductor is intended to provide
an effective ground-fault current path from the point of a ground fault
back to the source. The path must have sufficiently low impedance to
permit enough fault current to cause the circuit overcurrent protective
device to open promptly. The EGC normally carries no current and is
not intended to substitute for the grounded conductor.
2. Which NEC article is primarily devoted to grounding and
bonding requirements?
1
,A. Article 210
B. Article 225
C. Article 250
D. Article 310
Answer: C. Article 250
Rationale: NEC Article 250 contains the principal requirements for
grounding and bonding. It addresses grounded systems, grounding
electrode systems and conductors, equipment grounding conductors,
bonding, enclosures, separately derived systems, grounding electrode
conductors, and related subjects.
3. A 120/240-volt single-phase service has a grounded neutral
conductor and two ungrounded conductors. Where is the grounded
conductor normally connected to the equipment grounding system
at the service?
A. At every branch-circuit panelboard
B. Only at the farthest outlet
C. At the service disconnecting means/service equipment as permitted
by the NEC
D. At every receptacle
Answer: C. At the service disconnecting means/service equipment as
permitted by the NEC
Rationale: The service is the point where the grounded conductor is
connected to the grounding electrode system and where the grounded
conductor-to-equipment grounding connection is established as
permitted by Article 250. Downstream of the service disconnect, the
grounded conductor and equipment grounding conductors are
generally kept separated in accordance with the applicable NEC
provisions.
2
,4. Why is objectionable current on metal raceways and equipment
grounding conductors considered a serious problem?
A. It increases the frequency of the electrical system
B. It can place normal return current on metal paths that are intended to
remain non-current-carrying
C. It prevents transformers from operating
D. It automatically causes every circuit breaker to trip
Answer: B. It can place normal return current on metal paths that
are intended to remain non-current-carrying
Rationale: Bonding and grounding paths are normally intended to
carry fault current, not normal load current. Improper neutral-to-
ground connections downstream of the service can place neutral
current on raceways, equipment grounding conductors, building steel,
piping, and other conductive paths. This can create shock hazards,
electromagnetic interference, corrosion, and other problems.
5. Which conductor is normally intended to carry current under
normal operating conditions?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Grounded circuit conductor
D. Bonding jumper
Answer: C. Grounded circuit conductor
Rationale: The grounded circuit conductor, commonly called the
neutral in many systems, is a current-carrying conductor that
completes the normal circuit for loads connected between an
ungrounded conductor and the grounded conductor. Equipment
3
, grounding and bonding conductors are generally not intended to carry
normal operating current.
6. What is the fundamental distinction between grounding and
bonding?
A. Grounding connects conductive bodies together, while bonding
connects only to earth
B. Grounding establishes a connection to earth, while bonding
establishes electrical continuity between conductive parts
C. Grounding and bonding are exactly identical concepts
D. Bonding is required only for high-voltage systems
Answer: B. Grounding establishes a connection to earth, while
bonding establishes electrical continuity between conductive parts
Rationale: Grounding involves connecting a system or equipment to
earth through a grounding electrode system or other permitted means.
Bonding connects normally non-current-carrying conductive parts
together so that they remain at substantially equal potential and
provide an effective fault-current path. The two functions work
together but are not interchangeable.
7. A metal junction box contains several equipment grounding
conductors. What is the proper method of bonding the metal box?
A. Leave the box unbonded because the conductors are insulated
B. Connect the equipment grounding conductor(s) to the box using an
approved means
C. Connect the box only to the neutral conductor
D. Connect the box to a water pipe without an equipment grounding
conductor
4
EXAMINATION WITH ACTUAL QUESTIONS
AND VERIFIED ANSWERS, PLUS
EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. What is the primary purpose of the equipment grounding
conductor (EGC) in an electrical installation?
A. To carry the normal operating current of the circuit
B. To provide a low-impedance path for fault current back to the source
so the overcurrent protective device can operate
C. To stabilize the voltage between ungrounded conductors
D. To replace the grounded circuit conductor in a multiwire branch
circuit
Answer: B. To provide a low-impedance path for fault current back
to the source so the overcurrent protective device can operate
Rationale: The equipment grounding conductor is intended to provide
an effective ground-fault current path from the point of a ground fault
back to the source. The path must have sufficiently low impedance to
permit enough fault current to cause the circuit overcurrent protective
device to open promptly. The EGC normally carries no current and is
not intended to substitute for the grounded conductor.
2. Which NEC article is primarily devoted to grounding and
bonding requirements?
1
,A. Article 210
B. Article 225
C. Article 250
D. Article 310
Answer: C. Article 250
Rationale: NEC Article 250 contains the principal requirements for
grounding and bonding. It addresses grounded systems, grounding
electrode systems and conductors, equipment grounding conductors,
bonding, enclosures, separately derived systems, grounding electrode
conductors, and related subjects.
3. A 120/240-volt single-phase service has a grounded neutral
conductor and two ungrounded conductors. Where is the grounded
conductor normally connected to the equipment grounding system
at the service?
A. At every branch-circuit panelboard
B. Only at the farthest outlet
C. At the service disconnecting means/service equipment as permitted
by the NEC
D. At every receptacle
Answer: C. At the service disconnecting means/service equipment as
permitted by the NEC
Rationale: The service is the point where the grounded conductor is
connected to the grounding electrode system and where the grounded
conductor-to-equipment grounding connection is established as
permitted by Article 250. Downstream of the service disconnect, the
grounded conductor and equipment grounding conductors are
generally kept separated in accordance with the applicable NEC
provisions.
2
,4. Why is objectionable current on metal raceways and equipment
grounding conductors considered a serious problem?
A. It increases the frequency of the electrical system
B. It can place normal return current on metal paths that are intended to
remain non-current-carrying
C. It prevents transformers from operating
D. It automatically causes every circuit breaker to trip
Answer: B. It can place normal return current on metal paths that
are intended to remain non-current-carrying
Rationale: Bonding and grounding paths are normally intended to
carry fault current, not normal load current. Improper neutral-to-
ground connections downstream of the service can place neutral
current on raceways, equipment grounding conductors, building steel,
piping, and other conductive paths. This can create shock hazards,
electromagnetic interference, corrosion, and other problems.
5. Which conductor is normally intended to carry current under
normal operating conditions?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Grounded circuit conductor
D. Bonding jumper
Answer: C. Grounded circuit conductor
Rationale: The grounded circuit conductor, commonly called the
neutral in many systems, is a current-carrying conductor that
completes the normal circuit for loads connected between an
ungrounded conductor and the grounded conductor. Equipment
3
, grounding and bonding conductors are generally not intended to carry
normal operating current.
6. What is the fundamental distinction between grounding and
bonding?
A. Grounding connects conductive bodies together, while bonding
connects only to earth
B. Grounding establishes a connection to earth, while bonding
establishes electrical continuity between conductive parts
C. Grounding and bonding are exactly identical concepts
D. Bonding is required only for high-voltage systems
Answer: B. Grounding establishes a connection to earth, while
bonding establishes electrical continuity between conductive parts
Rationale: Grounding involves connecting a system or equipment to
earth through a grounding electrode system or other permitted means.
Bonding connects normally non-current-carrying conductive parts
together so that they remain at substantially equal potential and
provide an effective fault-current path. The two functions work
together but are not interchangeable.
7. A metal junction box contains several equipment grounding
conductors. What is the proper method of bonding the metal box?
A. Leave the box unbonded because the conductors are insulated
B. Connect the equipment grounding conductor(s) to the box using an
approved means
C. Connect the box only to the neutral conductor
D. Connect the box to a water pipe without an equipment grounding
conductor
4