NEIEP 400 Final Review | Complete Practice
Exam Questions with Verified Answers and
Detailed Rationales (100% Correct Answers) |
Latest Update 2026/2027 | Already Graded A+
Question 1
Which would you do to check for an open primary winding?
A. Measure the current through the primary while energized
B. Measure the resistance across the secondary
C. Measure the voltage across the primary while energized
D. Measure the resistance across the primary
Answer: D
Rationale: An open winding has infinite resistance. Measuring resistance across
the primary with an ohmmeter (de-energized) is the correct way to check for an
open circuit.
Question 2
What happens if more turns are added to each armature coil in a DC generator?
A. Increased voltage output
B. Zero current output
C. Decreased current output
D. Alternating current
Answer: A
Rationale: Induced voltage is proportional to the number of turns in the coil.
Adding turns increases the generated voltage.
Question 3
A minus sign in front of a reading on a digital voltmeter indicates which of the
following?
A. The voltage reading is negative
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,B. The positive lead is connected to the negative source
C. The meter is measuring AC voltage
D. The voltmeter is connected in reverse polarity
Answer: D
Rationale: A minus sign indicates the meter leads are reversed relative to the
polarity of the circuit being measured.
Question 4
Which of the following is a motor that can be run on both AC and DC?
A. Universal motor
B. Capacitor start motor
C. Shaded pole motor
D. Split phase motor
Answer: A
Rationale: A universal motor has a series-wound field and armature, allowing it to
operate on either AC or DC.
Question 5
You are installing a 30-horsepower induction motor for a hydraulic elevator. What
rating would you use to determine the wire size?
A. HDG
B. FLC
C. LRC
D. VRC
Answer: B
Rationale: Full-Load Current (FLC) is used to size conductors and overcurrent
protection for motors.
Question 6
How is an armature shaft balanced at the factory or repair facility?
A. Adding or removing epoxy weights to the shaft or windings
B. Polishing the commutator bars to remove carbon buildup
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,C. Replacing the brushes with a softer carbon compound
D. Tightening the bearing locknuts to increase tension
Answer: A
Rationale: Armature balancing is done by adding or removing small weights to
eliminate vibration.
Question 7
What does the Right-hand Rule for motors determine?
A. Direction of the induced voltage in a generator
B. Direction of the magnetic field around a wire
C. Direction of the current carrying conductor movement in a magnetic field
D. Direction of the magnetic flux lines in a coil
Answer: C
Rationale: The Right-hand Rule for motors predicts the direction of force (motion)
on a current-carrying conductor in a magnetic field.
Question 8
Which statement best describes eddy currents?
A. They are circulating currents set up by magnetic induction.
B. They are currents that are induced by the load resistance.
C. They are currents that flow in the primary winding only.
D. They are currents that flow only in DC circuits.
Answer: A
Rationale: Eddy currents are circulating currents induced in core material by
changing magnetic fields, causing heat losses.
Question 9
Which of the following is used to lubricate a ball bearing?
A. Brush
B. Grease
C. Water
D. Dirt
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, Answer: B
Rationale: Ball bearings are typically packed with grease for long-term
lubrication.
Question 10
A light electrical load on a commutator causes which of the following conditions?
A. Heavy Slot-Bar Marking
B. Soldering
C. All Of The Above
D. Threading
Answer: D
Rationale: Light loads can cause threading, a fine-line commutator wear pattern.
Heavy loads cause heavy slot-bar marking.
Question 11
A transformer has 728 turns on the primary winding and 56 turns on the secondary.
With 120 volts applied on the primary, what is the output voltage on the
secondary?
A. 7.25 volts
B. 9.23 volts
C. 15.6 volts
D. 1560 volts
Answer: B
Rationale: Vp/Vs = Np/Ns → 120/Vs = 728/56 = 13 → Vs = 120/13 = 9.23 V.
Question 12
Which of the following would describe a transformer with a primary current of 27
amps and a secondary current of 1 amp?
A. Riser
B. Step-down transformer
C. Step-up transformer
D. Isolation transformer
Page | 4
Exam Questions with Verified Answers and
Detailed Rationales (100% Correct Answers) |
Latest Update 2026/2027 | Already Graded A+
Question 1
Which would you do to check for an open primary winding?
A. Measure the current through the primary while energized
B. Measure the resistance across the secondary
C. Measure the voltage across the primary while energized
D. Measure the resistance across the primary
Answer: D
Rationale: An open winding has infinite resistance. Measuring resistance across
the primary with an ohmmeter (de-energized) is the correct way to check for an
open circuit.
Question 2
What happens if more turns are added to each armature coil in a DC generator?
A. Increased voltage output
B. Zero current output
C. Decreased current output
D. Alternating current
Answer: A
Rationale: Induced voltage is proportional to the number of turns in the coil.
Adding turns increases the generated voltage.
Question 3
A minus sign in front of a reading on a digital voltmeter indicates which of the
following?
A. The voltage reading is negative
Page | 1
,B. The positive lead is connected to the negative source
C. The meter is measuring AC voltage
D. The voltmeter is connected in reverse polarity
Answer: D
Rationale: A minus sign indicates the meter leads are reversed relative to the
polarity of the circuit being measured.
Question 4
Which of the following is a motor that can be run on both AC and DC?
A. Universal motor
B. Capacitor start motor
C. Shaded pole motor
D. Split phase motor
Answer: A
Rationale: A universal motor has a series-wound field and armature, allowing it to
operate on either AC or DC.
Question 5
You are installing a 30-horsepower induction motor for a hydraulic elevator. What
rating would you use to determine the wire size?
A. HDG
B. FLC
C. LRC
D. VRC
Answer: B
Rationale: Full-Load Current (FLC) is used to size conductors and overcurrent
protection for motors.
Question 6
How is an armature shaft balanced at the factory or repair facility?
A. Adding or removing epoxy weights to the shaft or windings
B. Polishing the commutator bars to remove carbon buildup
Page | 2
,C. Replacing the brushes with a softer carbon compound
D. Tightening the bearing locknuts to increase tension
Answer: A
Rationale: Armature balancing is done by adding or removing small weights to
eliminate vibration.
Question 7
What does the Right-hand Rule for motors determine?
A. Direction of the induced voltage in a generator
B. Direction of the magnetic field around a wire
C. Direction of the current carrying conductor movement in a magnetic field
D. Direction of the magnetic flux lines in a coil
Answer: C
Rationale: The Right-hand Rule for motors predicts the direction of force (motion)
on a current-carrying conductor in a magnetic field.
Question 8
Which statement best describes eddy currents?
A. They are circulating currents set up by magnetic induction.
B. They are currents that are induced by the load resistance.
C. They are currents that flow in the primary winding only.
D. They are currents that flow only in DC circuits.
Answer: A
Rationale: Eddy currents are circulating currents induced in core material by
changing magnetic fields, causing heat losses.
Question 9
Which of the following is used to lubricate a ball bearing?
A. Brush
B. Grease
C. Water
D. Dirt
Page | 3
, Answer: B
Rationale: Ball bearings are typically packed with grease for long-term
lubrication.
Question 10
A light electrical load on a commutator causes which of the following conditions?
A. Heavy Slot-Bar Marking
B. Soldering
C. All Of The Above
D. Threading
Answer: D
Rationale: Light loads can cause threading, a fine-line commutator wear pattern.
Heavy loads cause heavy slot-bar marking.
Question 11
A transformer has 728 turns on the primary winding and 56 turns on the secondary.
With 120 volts applied on the primary, what is the output voltage on the
secondary?
A. 7.25 volts
B. 9.23 volts
C. 15.6 volts
D. 1560 volts
Answer: B
Rationale: Vp/Vs = Np/Ns → 120/Vs = 728/56 = 13 → Vs = 120/13 = 9.23 V.
Question 12
Which of the following would describe a transformer with a primary current of 27
amps and a secondary current of 1 amp?
A. Riser
B. Step-down transformer
C. Step-up transformer
D. Isolation transformer
Page | 4
