Wyoming Master Electrician Examination | Latest
Verified Questions and Detailed Answers
OVERVIEW DESCRIPTION:
This Comprehensive set of questions is designed for the Wyoming Master Electrician
Examination, which assesses advanced proficiency in the National Electrical Code (NEC),
electrical theory, and standard industry practices. The assessment covers critical topics
including advanced wiring methods, complex load calculations, motor and transformer
installations, grounding and bonding requirements, and electrical service design. The
exam is administered by the International Code Council (ICC) and targets experienced
examinees seeking to demonstrate mastery in electrical system design, installation, and
safety protocols.
QUESTION 1
A continuous-duty motor has a nameplate full-load current rating of 20A, a service factor
of 1.15, and a marked temperature rise of 40°C. What is the maximum initial setting for a
separate overload device according to NEC 430.32(A)(1)?
A. 23 A
B. 25 A
C. 26 A
D. 28 A
CORRECT ANSWER: B
EXPERT RATIONALE: NEC 430.32(A)(1) requires overload devices to be sized at 125% of
nameplate for motors with a service factor of 1.15 or greater, or a temperature rise of
40°C or less. Otherwise, 115% is used. Given the specs, the calculation is 20A x 1.25 =
25A.
QUESTION 2
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A new mobile home is being connected to a site supply. According to NEC 550.10(A), the
power-supply cord must be a single, listed mobile home power-supply cord. What is the
minimum required rating for this cord?
A. 30 amperes
B. 40 amperes
C. 50 amperes
D. 60 amperes
CORRECT ANSWER: C
EXPERT RATIONALE: NEC 550.10(A) requires the mobile home power-supply cord to
have a minimum rating of 50 amperes. Modern mobile homes have electrical loads that
make the 50A rating a strict minimum standard for safety.
QUESTION 3
Electrical equipment operating at 120/240V to ground requires dedicated working space.
The installation fits Condition 1 (exposed live parts on one side, no live or grounded
parts on the other). According to NEC 110.26(A)(1), what is the minimum required clear
depth of working space in front of this equipment?
A. 3.5 ft
B. 4 ft
C. 5 ft
D. 3 ft
CORRECT ANSWER: D
EXPERT RATIONALE: NEC 110.26(A)(1) establishes working space depths based on
voltage to ground and conditions. For 120/240V equipment under Condition 1, the
required depth is 3 ft. This provides safe access for maintenance personnel.
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QUESTION 4
A restaurant service is being supplied by copper service-entrance conductors sized at 2/0
or 3/0. According to NEC Table 250.66, what is the minimum required size for the copper
grounding electrode conductor (GEC) connecting to a metal water pipe?
A. 6 AWG
B. 2 AWG
C. 1/0 AWG
D. 4 AWG
CORRECT ANSWER: D
EXPERT RATIONALE: NEC Table 250.66 dictates the sizing of the grounding electrode
conductor based on the size of the largest ungrounded service-entrance conductor. For
a copper service conductor sized 2/0 or 3/0, a minimum 4 AWG copper GEC is required
to safely dissipate fault currents.
QUESTION 5
A single-phase branch circuit supplies a 12A load located 100 feet from the distribution
panel. The circuit uses No. 10 AWG uncoated copper conductors, which have a resistance
of 1.2 ohms per 1000 feet. What is the approximate voltage drop for this circuit?
A. 1.4 V
B. 4.3 V
C. 2.9 V
D. 5.8 V
CORRECT ANSWER: C
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EXPERT RATIONALE: The single-phase voltage drop formula is VD = (2 x R x I x D) /
1000. Substituting the values: (2 x 1.2 x 12 x 100) / 1000 = 2.9 Volts. This calculation
helps ensure equipment receives adequate voltage.
QUESTION 6
An electrician is wiring an automotive fuel storage room, which is classified as a Class I,
Division 1 hazardous location. According to NEC 501.10(A), which of the following wiring
methods is permitted as the general rule for this location?
A. Electrical Metallic Tubing (EMT)
B. Rigid PVC Conduit
C. Liquidtight Flexible Nonmetallic Conduit (LFNC)
D. Threaded Rigid Metal Conduit (RMC) or Threaded Steel Intermediate Metal Conduit
(IMC)
CORRECT ANSWER: D
EXPERT RATIONALE: NEC 501.10(A) requires robust wiring methods like threaded Rigid
Metal Conduit (RMC) or threaded steel Intermediate Metal Conduit (IMC) in Class I,
Division 1 locations. These methods contain potential internal explosions.
QUESTION 7
A facility is installing a 20 HP dedicated fire pump motor. To ensure reliability during an
emergency, the overcurrent protection for the fire pump circuit must be sized differently
than standard motors. According to NEC 695.4(B)(2), the overcurrent protective device
must be sized to carry what current indefinitely?
A. 125% of the motor full-load current
B. 150% of the motor full-load current
C. The locked-rotor current of the fire pump motor
D. 250% of the motor full-load current