COMMERCIAL ELECTRICAL PLANS
EXAMINER EXAMINATION WITH ACTUAL
QUESTIONS AND VERIFIED ANSWERS,
PLUS EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. A commercial electrical plan indicates a 480Y/277 V, 3-phase, 4-
wire service supplying a large office building. The electrical load
schedule lists 900 A of connected load, but the calculated demand
load is only 620 A. The proposed service disconnect is rated 600 A.
What is the most appropriate plan-review conclusion?
A. Approve because the connected load exceeds the service rating only
slightly
B. Approve because demand load always replaces connected load for
service sizing
C. Reject or require correction because the calculated service load
exceeds the proposed 600 A service rating
D. Require the service to be sized at exactly 900 A
Answer: C.
Rationale: The service must be adequately sized for the calculated load
in accordance with the applicable NEC requirements. A calculated
demand load of 620 A cannot be supplied by a 600 A service simply
because the connected load is higher or because demand factors have
already been applied. The examiner should verify the load calculation
methodology, conductor ampacity, service equipment rating, and
overcurrent protection as a coordinated system.
1
,2. During review of a commercial tenant improvement, the plans
show a 120/208 V, 3-phase, 4-wire panelboard. Several single-phase
receptacle circuits are connected exclusively to phases A and B,
while phase C carries substantially less load. What is the primary
plan-review concern?
A. The panelboard must be converted to single-phase
B. The imbalance may cause excessive neutral current and uneven phase
loading
C. The neutral must always carry zero current
D. The panelboard voltage is incorrect for commercial receptacles
Answer: B.
Rationale: Proper phase distribution is important in a three-phase
commercial system. Excessive imbalance can increase voltage
imbalance, reduce system efficiency, and create unnecessary loading
on the neutral and phase conductors. The examiner should evaluate
the panel schedule and load calculation and require redistribution
where appropriate.
3. A commercial building contains a 208 V, 3-phase motor with a
nameplate current of 68 A. The designer proposes conductors based
solely on 68 A without applying any motor-specific requirements.
What should the plans examiner identify?
A. Motors are always sized from the service demand load only
B. Motor branch-circuit conductors may always equal the nameplate
current
C. Motor conductors, overcurrent protection, and disconnecting means
must be evaluated using the applicable motor provisions
D. Motors do not require overcurrent protection
Answer: C.
2
,Rationale: Motor circuits have specialized requirements that differ
from ordinary utilization loads. The examiner should verify conductor
sizing, branch-circuit short-circuit and ground-fault protection,
overload protection, disconnecting means, and other applicable motor
provisions. The motor nameplate information is an essential part of
this review.
4. A commercial electrical plan shows a 120 V, 20 A general-purpose
receptacle circuit serving several office receptacles. The plans do not
identify whether required receptacles in the space are AFCI
protected. What should the examiner do first?
A. Automatically reject the entire electrical design
B. Determine whether the occupancy and locations fall within the
applicable AFCI requirements of the adopted code
C. Require AFCI protection for every receptacle in every commercial
building
D. Remove all receptacles from the plan
Answer: B.
Rationale: AFCI requirements depend on the applicable NEC edition,
occupancy, circuit type, and location. A plans examiner should not
automatically apply residential requirements to every commercial
installation. The reviewer should identify whether the specific
commercial space is within the scope of the adopted AFCI provisions.
5. A commercial building service is supplied at 480Y/277 V. The
grounding electrode conductor is shown connecting the service
equipment to a building structural steel member. What should the
examiner verify?
3
, A. That structural steel is painted
B. That the steel qualifies as an available grounding electrode and is
properly bonded and connected as required
C. That the grounding electrode conductor is connected only to the
neutral bar in downstream panels
D. That grounding electrodes are optional for commercial buildings
Answer: B.
Rationale: Building structural metal may qualify as a grounding
electrode under the applicable NEC provisions when it meets the
required conditions. The examiner should verify the electrode
characteristics, accessibility, bonding, conductor sizing, connection
method, and relationship to other grounding electrodes.
6. A commercial service drawing shows the grounded conductor
bonded to the equipment grounding conductor in a downstream
distribution panel located 200 feet from the service disconnect.
What is the principal concern?
A. The panel is too far from the service
B. A downstream neutral-to-ground bond can create objectionable
current on equipment grounding paths
C. The grounded conductor must never be connected to anything
D. Every panel must have multiple neutral-to-ground bonds
Answer: B.
Rationale: The grounded conductor-to-equipment grounding
conductor connection is generally established at the service
disconnecting means or other specifically permitted location. Bonding
the neutral to ground downstream can place normal neutral current
on equipment grounding conductors and bonded metal parts, creating
objectionable current and potential shock hazards.
4
EXAMINER EXAMINATION WITH ACTUAL
QUESTIONS AND VERIFIED ANSWERS,
PLUS EXPLAINED RATIONALES/EXPERT
VERIFIED FOR GUARANTEED 100% PASS
2026/LATEST UPDATE/INSTANT
DOWNLOAD PDF
1. A commercial electrical plan indicates a 480Y/277 V, 3-phase, 4-
wire service supplying a large office building. The electrical load
schedule lists 900 A of connected load, but the calculated demand
load is only 620 A. The proposed service disconnect is rated 600 A.
What is the most appropriate plan-review conclusion?
A. Approve because the connected load exceeds the service rating only
slightly
B. Approve because demand load always replaces connected load for
service sizing
C. Reject or require correction because the calculated service load
exceeds the proposed 600 A service rating
D. Require the service to be sized at exactly 900 A
Answer: C.
Rationale: The service must be adequately sized for the calculated load
in accordance with the applicable NEC requirements. A calculated
demand load of 620 A cannot be supplied by a 600 A service simply
because the connected load is higher or because demand factors have
already been applied. The examiner should verify the load calculation
methodology, conductor ampacity, service equipment rating, and
overcurrent protection as a coordinated system.
1
,2. During review of a commercial tenant improvement, the plans
show a 120/208 V, 3-phase, 4-wire panelboard. Several single-phase
receptacle circuits are connected exclusively to phases A and B,
while phase C carries substantially less load. What is the primary
plan-review concern?
A. The panelboard must be converted to single-phase
B. The imbalance may cause excessive neutral current and uneven phase
loading
C. The neutral must always carry zero current
D. The panelboard voltage is incorrect for commercial receptacles
Answer: B.
Rationale: Proper phase distribution is important in a three-phase
commercial system. Excessive imbalance can increase voltage
imbalance, reduce system efficiency, and create unnecessary loading
on the neutral and phase conductors. The examiner should evaluate
the panel schedule and load calculation and require redistribution
where appropriate.
3. A commercial building contains a 208 V, 3-phase motor with a
nameplate current of 68 A. The designer proposes conductors based
solely on 68 A without applying any motor-specific requirements.
What should the plans examiner identify?
A. Motors are always sized from the service demand load only
B. Motor branch-circuit conductors may always equal the nameplate
current
C. Motor conductors, overcurrent protection, and disconnecting means
must be evaluated using the applicable motor provisions
D. Motors do not require overcurrent protection
Answer: C.
2
,Rationale: Motor circuits have specialized requirements that differ
from ordinary utilization loads. The examiner should verify conductor
sizing, branch-circuit short-circuit and ground-fault protection,
overload protection, disconnecting means, and other applicable motor
provisions. The motor nameplate information is an essential part of
this review.
4. A commercial electrical plan shows a 120 V, 20 A general-purpose
receptacle circuit serving several office receptacles. The plans do not
identify whether required receptacles in the space are AFCI
protected. What should the examiner do first?
A. Automatically reject the entire electrical design
B. Determine whether the occupancy and locations fall within the
applicable AFCI requirements of the adopted code
C. Require AFCI protection for every receptacle in every commercial
building
D. Remove all receptacles from the plan
Answer: B.
Rationale: AFCI requirements depend on the applicable NEC edition,
occupancy, circuit type, and location. A plans examiner should not
automatically apply residential requirements to every commercial
installation. The reviewer should identify whether the specific
commercial space is within the scope of the adopted AFCI provisions.
5. A commercial building service is supplied at 480Y/277 V. The
grounding electrode conductor is shown connecting the service
equipment to a building structural steel member. What should the
examiner verify?
3
, A. That structural steel is painted
B. That the steel qualifies as an available grounding electrode and is
properly bonded and connected as required
C. That the grounding electrode conductor is connected only to the
neutral bar in downstream panels
D. That grounding electrodes are optional for commercial buildings
Answer: B.
Rationale: Building structural metal may qualify as a grounding
electrode under the applicable NEC provisions when it meets the
required conditions. The examiner should verify the electrode
characteristics, accessibility, bonding, conductor sizing, connection
method, and relationship to other grounding electrodes.
6. A commercial service drawing shows the grounded conductor
bonded to the equipment grounding conductor in a downstream
distribution panel located 200 feet from the service disconnect.
What is the principal concern?
A. The panel is too far from the service
B. A downstream neutral-to-ground bond can create objectionable
current on equipment grounding paths
C. The grounded conductor must never be connected to anything
D. Every panel must have multiple neutral-to-ground bonds
Answer: B.
Rationale: The grounded conductor-to-equipment grounding
conductor connection is generally established at the service
disconnecting means or other specifically permitted location. Bonding
the neutral to ground downstream can place normal neutral current
on equipment grounding conductors and bonded metal parts, creating
objectionable current and potential shock hazards.
4
