NETA III EXAM 2026 COMPLETE EXAM QUESTIONS AND ACCURATE ANSWERS
|ALREADY PASSED!!
Question 1
Are the alternate sources for emergency systems required to be equipped with ground-fault
protection of equipment?
A) True, per NEC Article 700
B) True, only if the voltage is above 600V
C) False
D) False, except for healthcare facilities
E) True, but only for the primary source
Correct Answer: C) False
Rationale: According to NEC Article 700.26, ground-fault protection of equipment is not
required for the alternate source of emergency systems, although ground-fault indication is
required.
Question 2
Which ANSI/IEEE standard specifically covers the design and rating of SF6 (Sulfur
Hexafluoride) circuit breakers?
A) C37.01
B) C37.04
C) C37.10
D) C57.12
E) C37.20
Correct Answer: B) C37.04
Rationale: IEEE C37.04 is the standard for Rating Structure for AC High-Voltage Circuit
Breakers, which includes the specific requirements for SF6 gas-insulated technology.
Question 3
You measure the winding resistance of a 12.4kV, 1000kVA, Delta-Delta connected transformer.
H1-H2 is 42.0 microhms, H2-H3 is 41.9 microhms, and H3-H1 is 84.0 microhms. What is the
most likely diagnosis?
A) The transformer is in perfect condition
B) There is a short circuit in the H2 winding
C) One phase of the transformer is open
D) The test set leads were reversed
E) The core is saturated
Correct Answer: C) One phase of the transformer is open.
Rationale: In a delta configuration, if one winding is open, the resistance between two
terminals (H3-H1) will be the sum of the other two windings in series (42 + 41.9 ≈ 84), while
the other two measurements only see the single functional winding.
Question 4
When monitoring for entries into potentially stratified atmospheres in a confined space, at what
, 2
distance should the envelope be tested in the direction of travel and to each side?
A) 2 feet
B) 4 feet
C) 6 feet
D) 8 feet
E) 10 feet
Correct Answer: B) 4
Rationale: OSHA guidelines for confined space entry require testing 4 feet in the direction
of travel and to each side to ensure the worker is entering a safe breathing zone.
Question 5
According to NETA acceptance testing standards, the manufacturer should be consulted if
winding-resistance test values vary by more than what percentage from factory values?
A) 1 percent
B) 2 percent
C) 5 percent
D) 10 percent
E) 15 percent
Correct Answer: B) 2
Rationale: NETA-ATS specifies that winding resistance values should be compared to
factory results; a deviation of more than 2% between adjacent phases or factory data
indicates a potential connection or winding issue.
Question 6
Under which of the following conditions should a DC shunt motor NEVER be operated?
A) With a full load
B) At half speed
C) With the field circuit open
D) With the armature circuit open
E) In a high-humidity environment
Correct Answer: C) with the field circuit open
Rationale: In a DC shunt motor, if the field circuit opens, the counter-EMF drops
significantly, causing the motor to accelerate uncontrollably (run away) to a speed that can
result in mechanical destruction.
Question 7
What is the expected torque value for a 3/8" Grade 5 bolt using standard NETA/industry torque
tables?
A) 12 pound-feet
B) 20 pound-feet
C) 35 pound-feet
, 3
D) 45 pound-feet
E) 60 pound-feet
Correct Answer: B) 20
Rationale: Standard industry tables (and NETA ATS/MTS Appendix) list the recommended
torque for a 3/8" Grade 5 zinc-plated bolt as approximately 20 pound-feet.
Question 8
In the United States, what is the generally accepted limit of deviation from the nominal 60Hz
utility power frequency?
A) .01 Hz
B) .10 Hz
C) .50 Hz
D) 1.0 Hz
E) 2.0 Hz
Correct Answer: C) .50Hz
Rationale: Standard utility stability requirements generally maintain frequency within a
±0.5 Hz tolerance to ensure the synchronized operation of grid equipment.
Question 9
Power Factor (Dissipation Factor) testing is considered least effective or useful on which of the
following components?
A) Power Transformers
B) MV Circuit Breakers
C) MV Cable
D) Liquid-filled Bushings
E) Instrument Transformers
Correct Answer: C) MV Cable
Rationale: While Power Factor is critical for apparatus like transformers and breakers, it is
less effective for cables due to their large capacitive charging currents; VLF or partial
discharge testing is generally preferred for cables.
Question 10
When maintenance testing a 1500kVA transformer filled with silicone fluid, which of the
following insulating liquid tests is categorized as optional per NETA standards?
A) Dielectric breakdown
B) Neutralization number
C) Interfacial tension (ASTM D1298)
D) Visual examination
E) Color
Correct Answer: C) ASTM D1298
Rationale: NETA MTS classifies the specific gravity/interfacial tension test (ASTM D1298)
, 4
as an optional test for silicone fluid, whereas dielectric and neutralization tests are
required.
Question 11
Panelboards equipped with snap switches rated at 30 amps or less must be provided with
overcurrent protection not exceeding:
A) 100 amps
B) 150 amps
C) 200 amps
D) 400 amps
E) 600 amps
Correct Answer: C) 200 amps
Rationale: Per the NEC, to protect the smaller internal components and switches of a
panelboard, the overcurrent protection is capped at 200 amps when these switches are
present.
Question 12
Underground service conductors located between the terminals of the service equipment and the
service lateral are officially termed:
A) Branch Circuit Conductors
B) Feeders
C) Service Entrance Conductors
D) Secondary Surge Conductors
E) Grounding Electrode Conductors
Correct Answer: C) Service Entrance Conductors
Rationale: This is the NEC definition for the conductors that bridge the gap between the
utility's lateral and the customer's main disconnecting means.
Question 13
What is the primary purpose of a dual-element (time-delay) fuse?
A) To trip faster than a standard fuse
B) To protect against lightning strikes
C) To permit operation during a temporary overload (such as motor starting)
D) To eliminate the need for a disconnect switch
E) To sense ground faults only
Correct Answer: C) Operate with a temporary overload
Rationale: Dual-element fuses have a thermal cutout for long-term overloads (time delay)
and a fuse link for short circuits, allowing high inrush currents without blowing the fuse.
Question 14
What is the full-load current (FLA) for a 1 horsepower, 115-volt, single-phase AC motor?
|ALREADY PASSED!!
Question 1
Are the alternate sources for emergency systems required to be equipped with ground-fault
protection of equipment?
A) True, per NEC Article 700
B) True, only if the voltage is above 600V
C) False
D) False, except for healthcare facilities
E) True, but only for the primary source
Correct Answer: C) False
Rationale: According to NEC Article 700.26, ground-fault protection of equipment is not
required for the alternate source of emergency systems, although ground-fault indication is
required.
Question 2
Which ANSI/IEEE standard specifically covers the design and rating of SF6 (Sulfur
Hexafluoride) circuit breakers?
A) C37.01
B) C37.04
C) C37.10
D) C57.12
E) C37.20
Correct Answer: B) C37.04
Rationale: IEEE C37.04 is the standard for Rating Structure for AC High-Voltage Circuit
Breakers, which includes the specific requirements for SF6 gas-insulated technology.
Question 3
You measure the winding resistance of a 12.4kV, 1000kVA, Delta-Delta connected transformer.
H1-H2 is 42.0 microhms, H2-H3 is 41.9 microhms, and H3-H1 is 84.0 microhms. What is the
most likely diagnosis?
A) The transformer is in perfect condition
B) There is a short circuit in the H2 winding
C) One phase of the transformer is open
D) The test set leads were reversed
E) The core is saturated
Correct Answer: C) One phase of the transformer is open.
Rationale: In a delta configuration, if one winding is open, the resistance between two
terminals (H3-H1) will be the sum of the other two windings in series (42 + 41.9 ≈ 84), while
the other two measurements only see the single functional winding.
Question 4
When monitoring for entries into potentially stratified atmospheres in a confined space, at what
, 2
distance should the envelope be tested in the direction of travel and to each side?
A) 2 feet
B) 4 feet
C) 6 feet
D) 8 feet
E) 10 feet
Correct Answer: B) 4
Rationale: OSHA guidelines for confined space entry require testing 4 feet in the direction
of travel and to each side to ensure the worker is entering a safe breathing zone.
Question 5
According to NETA acceptance testing standards, the manufacturer should be consulted if
winding-resistance test values vary by more than what percentage from factory values?
A) 1 percent
B) 2 percent
C) 5 percent
D) 10 percent
E) 15 percent
Correct Answer: B) 2
Rationale: NETA-ATS specifies that winding resistance values should be compared to
factory results; a deviation of more than 2% between adjacent phases or factory data
indicates a potential connection or winding issue.
Question 6
Under which of the following conditions should a DC shunt motor NEVER be operated?
A) With a full load
B) At half speed
C) With the field circuit open
D) With the armature circuit open
E) In a high-humidity environment
Correct Answer: C) with the field circuit open
Rationale: In a DC shunt motor, if the field circuit opens, the counter-EMF drops
significantly, causing the motor to accelerate uncontrollably (run away) to a speed that can
result in mechanical destruction.
Question 7
What is the expected torque value for a 3/8" Grade 5 bolt using standard NETA/industry torque
tables?
A) 12 pound-feet
B) 20 pound-feet
C) 35 pound-feet
, 3
D) 45 pound-feet
E) 60 pound-feet
Correct Answer: B) 20
Rationale: Standard industry tables (and NETA ATS/MTS Appendix) list the recommended
torque for a 3/8" Grade 5 zinc-plated bolt as approximately 20 pound-feet.
Question 8
In the United States, what is the generally accepted limit of deviation from the nominal 60Hz
utility power frequency?
A) .01 Hz
B) .10 Hz
C) .50 Hz
D) 1.0 Hz
E) 2.0 Hz
Correct Answer: C) .50Hz
Rationale: Standard utility stability requirements generally maintain frequency within a
±0.5 Hz tolerance to ensure the synchronized operation of grid equipment.
Question 9
Power Factor (Dissipation Factor) testing is considered least effective or useful on which of the
following components?
A) Power Transformers
B) MV Circuit Breakers
C) MV Cable
D) Liquid-filled Bushings
E) Instrument Transformers
Correct Answer: C) MV Cable
Rationale: While Power Factor is critical for apparatus like transformers and breakers, it is
less effective for cables due to their large capacitive charging currents; VLF or partial
discharge testing is generally preferred for cables.
Question 10
When maintenance testing a 1500kVA transformer filled with silicone fluid, which of the
following insulating liquid tests is categorized as optional per NETA standards?
A) Dielectric breakdown
B) Neutralization number
C) Interfacial tension (ASTM D1298)
D) Visual examination
E) Color
Correct Answer: C) ASTM D1298
Rationale: NETA MTS classifies the specific gravity/interfacial tension test (ASTM D1298)
, 4
as an optional test for silicone fluid, whereas dielectric and neutralization tests are
required.
Question 11
Panelboards equipped with snap switches rated at 30 amps or less must be provided with
overcurrent protection not exceeding:
A) 100 amps
B) 150 amps
C) 200 amps
D) 400 amps
E) 600 amps
Correct Answer: C) 200 amps
Rationale: Per the NEC, to protect the smaller internal components and switches of a
panelboard, the overcurrent protection is capped at 200 amps when these switches are
present.
Question 12
Underground service conductors located between the terminals of the service equipment and the
service lateral are officially termed:
A) Branch Circuit Conductors
B) Feeders
C) Service Entrance Conductors
D) Secondary Surge Conductors
E) Grounding Electrode Conductors
Correct Answer: C) Service Entrance Conductors
Rationale: This is the NEC definition for the conductors that bridge the gap between the
utility's lateral and the customer's main disconnecting means.
Question 13
What is the primary purpose of a dual-element (time-delay) fuse?
A) To trip faster than a standard fuse
B) To protect against lightning strikes
C) To permit operation during a temporary overload (such as motor starting)
D) To eliminate the need for a disconnect switch
E) To sense ground faults only
Correct Answer: C) Operate with a temporary overload
Rationale: Dual-element fuses have a thermal cutout for long-term overloads (time delay)
and a fuse link for short circuits, allowing high inrush currents without blowing the fuse.
Question 14
What is the full-load current (FLA) for a 1 horsepower, 115-volt, single-phase AC motor?
