NCBEEC – Grounding & Special Systems
Electrical Contractor Examination Questions
and Correct Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant Download Pdf
1. What is the primary purpose of an equipment grounding
conductor (EGC)?
A. To carry the normal current of the circuit
B. To increase circuit voltage
C. To provide a low-impedance path for fault current
D. To replace the grounded conductor
Rationale: The equipment grounding conductor provides a low-
impedance path for fault current so that overcurrent protective
devices can operate promptly and disconnect the faulted circuit. It
normally does not carry circuit load current.
2. Which conductor is normally identified by a continuous white or
gray finish?
,A. Equipment grounding conductor
B. Ungrounded conductor
C. Grounded circuit conductor
D. Bonding jumper
Rationale: The grounded conductor is generally identified by white or
gray insulation or an appropriate marking method. Green is reserved
for equipment grounding conductors and bonding conductors.
3. Which color is most commonly used to identify an equipment
grounding conductor?
A. White
B. Gray
C. Red
D. Green or bare
Rationale: Equipment grounding conductors are commonly bare,
covered with green insulation, or identified by permitted green
markings. White and gray are associated with grounded conductors.
4. What is the primary purpose of bonding?
A. To increase resistance between metal parts
B. To provide a normal return path for all load current
,C. To establish electrical continuity between conductive parts
D. To eliminate the need for overcurrent protection
Rationale: Bonding connects normally non-current-carrying
conductive parts together so they remain at substantially the same
electrical potential and provide an effective fault-current path.
5. A metal equipment enclosure contains a circuit supplied by a
grounding-type wiring method. What should normally be
connected to the enclosure?
A. Only the neutral conductor
B. Only the ungrounded conductor
C. The equipment grounding conductor
D. The service neutral only
Rationale: The equipment grounding conductor is connected to non-
current-carrying metal equipment enclosures to establish an effective
grounding-fault current path.
6. At a separately derived system, where is the system bonding
jumper generally connected?
A. Only at the first branch-circuit receptacle
B. Between two ungrounded conductors
C. At the source or first disconnecting means as permitted by the
, installation
D. Only at the grounding electrode
Rationale: A separately derived system requires a system bonding
jumper to establish the relationship between the derived system's
grounded conductor and the grounding/bonding system at the
permitted location.
7. Which of the following is a grounding electrode?
A. Plastic junction box
B. PVC conduit
C. Metal underground water pipe meeting applicable requirements
D. Nonmetallic cable clamp
Rationale: A qualifying metal underground water pipe is recognized as
a grounding electrode. Other recognized electrodes can include
concrete-encased electrodes, ground rings, and certain building steel.
8. What is the purpose of a grounding electrode conductor (GEC)?
A. To carry normal branch-circuit load current
B. To replace an equipment grounding conductor
C. To connect the grounded system or equipment to the grounding
electrode system
D. To increase the circuit's operating voltage
Electrical Contractor Examination Questions
and Correct Answers (Verified Answers) Plus
Rationale 2027 Q&A| Instant Download Pdf
1. What is the primary purpose of an equipment grounding
conductor (EGC)?
A. To carry the normal current of the circuit
B. To increase circuit voltage
C. To provide a low-impedance path for fault current
D. To replace the grounded conductor
Rationale: The equipment grounding conductor provides a low-
impedance path for fault current so that overcurrent protective
devices can operate promptly and disconnect the faulted circuit. It
normally does not carry circuit load current.
2. Which conductor is normally identified by a continuous white or
gray finish?
,A. Equipment grounding conductor
B. Ungrounded conductor
C. Grounded circuit conductor
D. Bonding jumper
Rationale: The grounded conductor is generally identified by white or
gray insulation or an appropriate marking method. Green is reserved
for equipment grounding conductors and bonding conductors.
3. Which color is most commonly used to identify an equipment
grounding conductor?
A. White
B. Gray
C. Red
D. Green or bare
Rationale: Equipment grounding conductors are commonly bare,
covered with green insulation, or identified by permitted green
markings. White and gray are associated with grounded conductors.
4. What is the primary purpose of bonding?
A. To increase resistance between metal parts
B. To provide a normal return path for all load current
,C. To establish electrical continuity between conductive parts
D. To eliminate the need for overcurrent protection
Rationale: Bonding connects normally non-current-carrying
conductive parts together so they remain at substantially the same
electrical potential and provide an effective fault-current path.
5. A metal equipment enclosure contains a circuit supplied by a
grounding-type wiring method. What should normally be
connected to the enclosure?
A. Only the neutral conductor
B. Only the ungrounded conductor
C. The equipment grounding conductor
D. The service neutral only
Rationale: The equipment grounding conductor is connected to non-
current-carrying metal equipment enclosures to establish an effective
grounding-fault current path.
6. At a separately derived system, where is the system bonding
jumper generally connected?
A. Only at the first branch-circuit receptacle
B. Between two ungrounded conductors
C. At the source or first disconnecting means as permitted by the
, installation
D. Only at the grounding electrode
Rationale: A separately derived system requires a system bonding
jumper to establish the relationship between the derived system's
grounded conductor and the grounding/bonding system at the
permitted location.
7. Which of the following is a grounding electrode?
A. Plastic junction box
B. PVC conduit
C. Metal underground water pipe meeting applicable requirements
D. Nonmetallic cable clamp
Rationale: A qualifying metal underground water pipe is recognized as
a grounding electrode. Other recognized electrodes can include
concrete-encased electrodes, ground rings, and certain building steel.
8. What is the purpose of a grounding electrode conductor (GEC)?
A. To carry normal branch-circuit load current
B. To replace an equipment grounding conductor
C. To connect the grounded system or equipment to the grounding
electrode system
D. To increase the circuit's operating voltage
