NYC DCAS ELECTRICIAN EXAM – COMPLETE PRACTICE TEST
BANK QUESTIONS WITH 100% CORRECT ANSWERS,
DETAILED NEC CODE RATIONALES (2017/2020), NYC
AMENDMENTS, ELECTRICAL THEORY, MOTOR CONTROLS,
GROUNDING, HAZARDOUS LOCATIONS, AND SAFETY (NFPA
70E/OSHA) – UPDATED FOR NYC ADMINISTRATIVE CODE
1. What is the maximum permitted distance between support straps
for a vertical run of 1-inch rigid metal conduit (RMC) in a commercial
installation per NYC amendments?
A) 10 feet
B) 12 feet
C) 16 feet
D) 20 feet
Explanation: NYC amendments align with NEC 344.30(B)(2), which
allows vertical RMC supports at 20-foot intervals for 1-inch and larger
sizes when properly fastened.
2. When sizing a transformer for a 3-phase, 480V primary to
208Y/120V secondary, if the secondary load is 75 kVA, what is the
minimum primary overcurrent protection rating permitted with
primary-only protection?
A) 100A
B) 125A
C) 150A
D) 175A
Explanation: Primary current = 75,000/(480×√3) = 90.2A. NEC 450.3(B)
,allows 125% for primary-only protection: 90.2×1.25 = 112.8A → next
standard size per 240.6 is 125A.
3. In a patient care area of a healthcare facility, what is the minimum
insulation voltage rating required for the equipment grounding
conductor serving receptacles?
A) 300V
B) 600V
C) 1000V
D) No insulation required
Explanation: NEC 517.13(A) requires an insulated grounding conductor
in patient care areas, rated at least 600V, with green insulation (solid
green or green with yellow stripe).
4. What is the maximum allowable conduit fill percentage for a
raceway containing three or more conductors of the same size per NEC
Chapter 9, Table 1?
A) 31%
B) 40%
C) 53%
D) 60%
Explanation: For three or more conductors, the cross-sectional fill is
limited to 40% of the conduit’s interior area.
5. Which of the following locations in a dwelling unit requires AFCI
protection for branch circuits per NEC 210.12?
A) Kitchen refrigerator receptacle
B) Bathroom receptacle
C) Laundry room receptacle
D) Garage door opener receptacle
,Explanation: AFCI protection is required in all dwelling unit areas except
bathrooms, garages, and outdoor outlets; laundry rooms are explicitly
included.
6. What is the minimum size copper bonding jumper for a metal water
pipe used as a grounding electrode where the service-entrance
conductors are 250 kcmil copper?
A) #6 AWG
B) #4 AWG
C) #2 AWG
D) #1/0 AWG
Explanation: Per NEC Table 250.66, for 250 kcmil copper service
conductors, the bonding jumper must be at least 1/0 AWG copper.
7. What is the minimum copper conductor size (THHN, 75°C terminals)
required for a branch circuit supplying a 15 HP, 230V, 3-phase motor
with a full-load current of 42A?
A) #8 AWG
B) #6 AWG
C) #4 AWG
D) #3 AWG
Explanation: NEC 430.22 requires conductor ampacity ≥ 125% × FLC =
42×1.25 = 52.5A. #6 THHN at 75°C is rated 65A (#8 is only 50A).
8. According to NYC Electrical Code, which wiring method is generally
prohibited in buildings over 75 feet in height unless enclosed in a shaft
or protected by automatic sprinklers?
A) Electrical metallic tubing (EMT)
B) Rigid metal conduit (RMC)
C) Nonmetallic-sheathed cable (NM)
, D) Intermediate metal conduit (IMC)
Explanation: NYC amendments strictly restrict NM cable (Romex) in
high-rise buildings over 75 feet without additional fire protection; EMT,
RMC, and IMC are permitted.
9. What is the minimum clearance required for service-drop
conductors above a residential flat roof that is not accessible to
pedestrians, per NEC 230.24?
A) 8 feet
B) 10 feet
C) 12 feet
D) 15 feet
Explanation: NEC 230.24(A) requires a minimum of 8 feet clearance
over flat roofs not subject to pedestrian traffic.
10. When installing a subpanel in a separate building fed by a 100A
feeder, what is the minimum size copper equipment grounding
conductor required?
A) #10 AWG
B) #8 AWG
C) #6 AWG
D) #4 AWG
Explanation: NEC Table 250.122 requires a #8 AWG copper equipment
grounding conductor for a 100A overcurrent protective device.
11. What is the maximum number of 14 AWG THHN conductors
permitted in a 1-inch EMT conduit using the 40% fill rule?
A) 10
B) 15
C) 20
BANK QUESTIONS WITH 100% CORRECT ANSWERS,
DETAILED NEC CODE RATIONALES (2017/2020), NYC
AMENDMENTS, ELECTRICAL THEORY, MOTOR CONTROLS,
GROUNDING, HAZARDOUS LOCATIONS, AND SAFETY (NFPA
70E/OSHA) – UPDATED FOR NYC ADMINISTRATIVE CODE
1. What is the maximum permitted distance between support straps
for a vertical run of 1-inch rigid metal conduit (RMC) in a commercial
installation per NYC amendments?
A) 10 feet
B) 12 feet
C) 16 feet
D) 20 feet
Explanation: NYC amendments align with NEC 344.30(B)(2), which
allows vertical RMC supports at 20-foot intervals for 1-inch and larger
sizes when properly fastened.
2. When sizing a transformer for a 3-phase, 480V primary to
208Y/120V secondary, if the secondary load is 75 kVA, what is the
minimum primary overcurrent protection rating permitted with
primary-only protection?
A) 100A
B) 125A
C) 150A
D) 175A
Explanation: Primary current = 75,000/(480×√3) = 90.2A. NEC 450.3(B)
,allows 125% for primary-only protection: 90.2×1.25 = 112.8A → next
standard size per 240.6 is 125A.
3. In a patient care area of a healthcare facility, what is the minimum
insulation voltage rating required for the equipment grounding
conductor serving receptacles?
A) 300V
B) 600V
C) 1000V
D) No insulation required
Explanation: NEC 517.13(A) requires an insulated grounding conductor
in patient care areas, rated at least 600V, with green insulation (solid
green or green with yellow stripe).
4. What is the maximum allowable conduit fill percentage for a
raceway containing three or more conductors of the same size per NEC
Chapter 9, Table 1?
A) 31%
B) 40%
C) 53%
D) 60%
Explanation: For three or more conductors, the cross-sectional fill is
limited to 40% of the conduit’s interior area.
5. Which of the following locations in a dwelling unit requires AFCI
protection for branch circuits per NEC 210.12?
A) Kitchen refrigerator receptacle
B) Bathroom receptacle
C) Laundry room receptacle
D) Garage door opener receptacle
,Explanation: AFCI protection is required in all dwelling unit areas except
bathrooms, garages, and outdoor outlets; laundry rooms are explicitly
included.
6. What is the minimum size copper bonding jumper for a metal water
pipe used as a grounding electrode where the service-entrance
conductors are 250 kcmil copper?
A) #6 AWG
B) #4 AWG
C) #2 AWG
D) #1/0 AWG
Explanation: Per NEC Table 250.66, for 250 kcmil copper service
conductors, the bonding jumper must be at least 1/0 AWG copper.
7. What is the minimum copper conductor size (THHN, 75°C terminals)
required for a branch circuit supplying a 15 HP, 230V, 3-phase motor
with a full-load current of 42A?
A) #8 AWG
B) #6 AWG
C) #4 AWG
D) #3 AWG
Explanation: NEC 430.22 requires conductor ampacity ≥ 125% × FLC =
42×1.25 = 52.5A. #6 THHN at 75°C is rated 65A (#8 is only 50A).
8. According to NYC Electrical Code, which wiring method is generally
prohibited in buildings over 75 feet in height unless enclosed in a shaft
or protected by automatic sprinklers?
A) Electrical metallic tubing (EMT)
B) Rigid metal conduit (RMC)
C) Nonmetallic-sheathed cable (NM)
, D) Intermediate metal conduit (IMC)
Explanation: NYC amendments strictly restrict NM cable (Romex) in
high-rise buildings over 75 feet without additional fire protection; EMT,
RMC, and IMC are permitted.
9. What is the minimum clearance required for service-drop
conductors above a residential flat roof that is not accessible to
pedestrians, per NEC 230.24?
A) 8 feet
B) 10 feet
C) 12 feet
D) 15 feet
Explanation: NEC 230.24(A) requires a minimum of 8 feet clearance
over flat roofs not subject to pedestrian traffic.
10. When installing a subpanel in a separate building fed by a 100A
feeder, what is the minimum size copper equipment grounding
conductor required?
A) #10 AWG
B) #8 AWG
C) #6 AWG
D) #4 AWG
Explanation: NEC Table 250.122 requires a #8 AWG copper equipment
grounding conductor for a 100A overcurrent protective device.
11. What is the maximum number of 14 AWG THHN conductors
permitted in a 1-inch EMT conduit using the 40% fill rule?
A) 10
B) 15
C) 20
