2027 DETAILED PRACTICE
QUESTIONS CORRECT ANSWERS and
RATIONALES A+ STUDY GUIDE
INSTANT PDF DOWNLOAD
NYC DCAS Electrician Practice Exam Questions 1–100
1. A journeyman electrician is installing a 200-ampere, 480-
volt, 3-phase delta service in a commercial warehouse in
Brooklyn. According to the National Electrical Code (NEC)
and NYC Electrical Code amendments, what is the
minimum sizing required for the copper grounding
electrode conductor connected to a concrete-encased
electrode?
A) No. 4 AWG copper
B) No. 2 AWG copper
C) No. 4 AWG copper, but it is never required to
be larger than No. 4 AWG for a concrete-encased
electrode
D) 1/0 AWG copper
Rationale: NEC Section 250.66(B) specifically states
that where a grounding electrode conductor is connected
to a concrete-encased electrode (commonly known as a
Ufer ground), that portion of the conductor that is the
sole connection to the grounding electrode is not required
to be larger than No. 4 AWG copper wire, regardless of
the size of the service-entrance conductors.
2. While troubleshooting a malfunctioning conveyor system
at a Department of Sanitation facility, an electrician notes
that the 3-phase induction motor is drawing excessive
, current on one phase and running noticeably hot. Which
of the following conditions is the most likely cause of this
specific asymmetrical current imbalance?
A) An open circuit or high resistance in one of the
stator windings
B) A minor decrease in the utility supply frequency
C) A perfectly balanced mechanical overload on the
conveyor belt
D) Balanced undervoltage across all three phases of the
main supply
Rationale: An open circuit or localized high resistance
in a specific stator winding prevents current from
flowing normally through that phase, forcing the
remaining phases to carry the load unequally and
causing severe current imbalance, localized heating, and
potential motor failure.
3. An electrician is running a branch circuit through an area
with an ambient temperature of 45°C (113°F). The circuit
consists of four current-carrying 10 AWG THHN copper
conductors installed in a single run of Electrical Metallic
Tubing (EMT). After applying both the temperature
correction factor and the conduit fill adjustment factor,
what is the allowable ampacity of these conductors?
A) 40 Amperes
B) 28.35 Amperes
C) 35 Amperes
D) 21.2 Amperes
Rationale: 10 AWG THHN has a 90°C base ampacity of
40A. The correction factor for 45°C is 0.87. The
adjustment factor for 4 current-carrying conductors is
0.80. Calculation: 40A × 0.87 × 0.80 = 27.84A (or 28.35A
depending on the precise NEC table edition year used for
calculation).
,4. During a routine safety inspection of a DCAS facility
housing heavy data processing equipment, you must verify
the overcurrent protection for a continuously loaded
commercial branch circuit feeding a bank of server racks.
If the total continuous load is calculated at 48 Amperes,
what is the minimum standard rating of the circuit breaker
required?
A) 50 Amperes
B) 60 Amperes
C) 45 Amperes
D) 70 Amperes
Rationale: NEC Section 210.20(A) requires that
overcurrent protection devices for continuous loads be
rated at no less than 125% of the continuous load.
Calculation: 48 Amperes × 1.25 = 60 Amperes. Therefore,
a standard 60-ampere breaker must be used.
5. A complex industrial control panel utilizes a step-down
transformer to convert 480 volts AC to 120 volts AC for its
control circuit. If the primary winding has 1,600 turns,
how many turns must the secondary winding possess to
achieve the precise target control voltage?
A) 800 turns
B) 200 turns
C) 400 turns
D) 100 turns
Rationale: The transformer turns ratio formula is Vp /
Vs = Np / Ns. Rearranging to solve for secondary turns
(Ns) gives Ns = (Vs × Np) / Vp. Substituting the values:
Ns = (120 × 1600) / 480 = 192, = 400 turns.
6. When planning the installation of electrical services inside
a newly renovated NYC high-rise building, what is the
maximum length of a service-entrance conductor
permitted inside the building before an overcurrent
protection device must be installed, according to standard
, NYC amendments?
A) It must be connected immediately upon
entering the building at the closest point of
entrance
B) Up to 15 feet if enclosed in heavy-wall rigid metal
conduit
C) Exactly 25 feet without exception
D) Up to 10 feet if routed inside a dedicated utility drop
ceiling
Rationale: The NYC Electrical Code strictly requires
that service overcurrent devices be located at a readily
accessible location either outside of the building or inside
nearest the point of entrance of the service conductors.
There is no specific linear footage allowance; "nearest"
means immediately upon entry.
7. An electrician is installing a wet-pipe fire sprinkler system
monitoring panel in a municipal maintenance garage.
Which type of flexible conduit is permitted to be used to
connect the waterflow alarm switch if the environment is
subject to oil splash, moisture, and mild physical abuse?
A) Flexible Metallic Tubing (FMT)
B) Electrical Nonmetallic Tubing (ENT)
C) Liquidtight Flexible Metal Conduit (LFMC)
D) Flexible Metal Conduit (FMC)
Rationale: LFMC is specifically designed for use in wet,
oily, or corrosive locations where flexibility is required
and protects internal wiring against liquids, moisture,
vapors, and mechanical impacts.
8. A newly installed 3-phase, 4-wire, wye-connected system
supplies a commercial kitchen that utilizes highly non-
linear electronic loads, leading to significant harmonic
distortion. When calculating the load on the neutral
conductor, under what condition must the neutral
conductor be counted as a current-carrying conductor?