NETA III FINAL PAPER 2025/2026 QUESTIONS WITH
ANSWERS RATED A+
✔✔Building A is supplied with 120/240 volt single-phase power from Building B on the
same property. Building B is supplied from a three-wire with two ungrounded conductors
and one neutral without any metallic water pipe or other metal equipment connections to
the building or equipment ground fault protection installed. The neutral conductor must:
- ✔✔Not be connected to a grounding electrode in the second building
✔✔The reactance of a synchronous machine depends upon: - ✔✔Degree of saturation
of magnetic core
✔✔Hydrogen clings to the positive plate in primary cell and thus effectively reduces the
effective surface of this plate resulting in reduction in the EMF of the cell. This
phenomenon is known as: - ✔✔Polarization
✔✔Optional standby systems are typically installed to provide an alternate source of
power for which of the following? - ✔✔data processing and communication systems
✔✔A three-phase bolted fault would primarily produce which type of current? -
✔✔Positive sequence current.
✔✔Cables that are not approved for mounting in contact with a building or other
structure shall be mounted on insulating supports installed at intervals not exceeding
_____. - ✔✔15 feet
✔✔Power transformer cooling classes went through major changes in the United States
when IEEE Standard C57.12.00-2000 adopted the modern four-letter designation.
Which of the following old designations does not match the new? - ✔✔OA/FOA =
ONAN/ONAF
✔✔ASTM test method D924 measures which of the following? - ✔✔percent
✔✔Which of the following electrical tests would you not perform on a new capacitor? -
✔✔Dielectric withstand voltage
✔✔When conducting an ASTM D1816 dielectric breakdown test, the fluid is
continuously stirred. - ✔✔True
✔✔Capacitance is directly proportional to the length of the conducting plates, not width.
- ✔✔False
,✔✔Which is the correct definition of TDD as put forth in IEEE 1159? - ✔✔TDD is the
total rms harmonic current distortion, in percent of the maximum demand load current
(15 or 30 min demand).
✔✔Which of the following maintenance tests is optional for a 13200-480Y/277V
2500kVA dry-type transformer? - ✔✔resistance of each winding at designated tap
✔✔Which of the following is is one optional test given for microprocessor protective
relays in Section 7.9.2 of ANSI/NETA MTS? - ✔✔Functional operation of each element
✔✔When arcing occurs in SF6 , what is one hazardous byproduct? - ✔✔metal fluorides
✔✔In case of multiple grounding connections, in order to reduce the objectionable
current all grounding connections shall be disconnected. - ✔✔False
✔✔What does a kilowatt-hour meter read? - ✔✔Energy Use
✔✔A switch or circuit breaker enclosure may be used as a raceway if the conductor fill
does not exceed _____ . - ✔✔40%
✔✔What is the minimum acceptable test limit for an ASTM D877 test on mineral oil
used in new 69kV equipment? - ✔✔30kV
✔✔What is the NETA Minimum DC Test Voltage for an Insulation-Resistance test on a
5kV liquid-filled transformer winding? - ✔✔2500
✔✔One advantage DC type motors have over AC types is that: - ✔✔their speed can be
easily varied
✔✔Grounding conductors and bonding jumpers shall not be installed in the same
raceway containing service conductors per NEC. - ✔✔False
✔✔Which test is required for insulating liquid taken from an in-service HV OCB per
NETA standards? - ✔✔ASTM D877
✔✔In which protection scheme does the magnitude and phase angle of the current
flowing at each end of the line determine whether an internal fault exists. - ✔✔Pilot-Wire
✔✔Which of the following ASTM test methods would best measure the neutralization
(acid) number of insulating liquid? - ✔✔D974
✔✔Dielectric Breakdown - ✔✔D877
, ✔✔Dielectric Breakdown kV minimum @ 1mm & 2mm - ✔✔D1816
✔✔Interfacial Tension (mN/m min.) - ✔✔D971
✔✔Neutralization Number (mg KOH/g max.)
Neutralization Number of Less Flammable - ✔✔D974
D664
✔✔Water content - ✔✔D1533
✔✔Power Factor @ 25 C and 100 C - ✔✔D924
✔✔Color Test of insulating liquid - ✔✔D1500
✔✔Visual Condition of insulating liquid - ✔✔D1524
✔✔Specific Gravity - ✔✔D1298
✔✔Fire Point of insulating liquid - ✔✔D92
✔✔What is the expected Maximum Trip Time (in Seconds) for a 480V, 100A molded-
case circuit breaker inverse time test at 300% of Rated Continuous Current? - ✔✔160
✔✔The minimum allowable work space around electrical equipment is _____ inches
wide. - ✔✔30
✔✔Where raceways contain insulated circuit conductors _____ and larger, the
conductors shall be protected from abrasion during and after installation by an identified
fitting providing a smoothly rounded insulating surface. - ✔✔4 AWG
✔✔The power factor of new mineral oil at 100C for equipment rated 69kV and below
should be _____ % or less. - ✔✔0.40
✔✔Power fuse resistance readings on a MV Switch deviate by than 30%. What is the
NETA recommendation? - ✔✔Inspect
✔✔The Angle of Zone of protection of a lightning protection system is approximately: -
✔✔45 degrees
✔✔Concrete-Encased Grounding Electrodes are often referred to as: - ✔✔Ufer Ground
✔✔You are asked to analyze a thermographic image of a single insulated electrical
connection under 60% load, the ambient temperature recorded was 72°F and
ANSWERS RATED A+
✔✔Building A is supplied with 120/240 volt single-phase power from Building B on the
same property. Building B is supplied from a three-wire with two ungrounded conductors
and one neutral without any metallic water pipe or other metal equipment connections to
the building or equipment ground fault protection installed. The neutral conductor must:
- ✔✔Not be connected to a grounding electrode in the second building
✔✔The reactance of a synchronous machine depends upon: - ✔✔Degree of saturation
of magnetic core
✔✔Hydrogen clings to the positive plate in primary cell and thus effectively reduces the
effective surface of this plate resulting in reduction in the EMF of the cell. This
phenomenon is known as: - ✔✔Polarization
✔✔Optional standby systems are typically installed to provide an alternate source of
power for which of the following? - ✔✔data processing and communication systems
✔✔A three-phase bolted fault would primarily produce which type of current? -
✔✔Positive sequence current.
✔✔Cables that are not approved for mounting in contact with a building or other
structure shall be mounted on insulating supports installed at intervals not exceeding
_____. - ✔✔15 feet
✔✔Power transformer cooling classes went through major changes in the United States
when IEEE Standard C57.12.00-2000 adopted the modern four-letter designation.
Which of the following old designations does not match the new? - ✔✔OA/FOA =
ONAN/ONAF
✔✔ASTM test method D924 measures which of the following? - ✔✔percent
✔✔Which of the following electrical tests would you not perform on a new capacitor? -
✔✔Dielectric withstand voltage
✔✔When conducting an ASTM D1816 dielectric breakdown test, the fluid is
continuously stirred. - ✔✔True
✔✔Capacitance is directly proportional to the length of the conducting plates, not width.
- ✔✔False
,✔✔Which is the correct definition of TDD as put forth in IEEE 1159? - ✔✔TDD is the
total rms harmonic current distortion, in percent of the maximum demand load current
(15 or 30 min demand).
✔✔Which of the following maintenance tests is optional for a 13200-480Y/277V
2500kVA dry-type transformer? - ✔✔resistance of each winding at designated tap
✔✔Which of the following is is one optional test given for microprocessor protective
relays in Section 7.9.2 of ANSI/NETA MTS? - ✔✔Functional operation of each element
✔✔When arcing occurs in SF6 , what is one hazardous byproduct? - ✔✔metal fluorides
✔✔In case of multiple grounding connections, in order to reduce the objectionable
current all grounding connections shall be disconnected. - ✔✔False
✔✔What does a kilowatt-hour meter read? - ✔✔Energy Use
✔✔A switch or circuit breaker enclosure may be used as a raceway if the conductor fill
does not exceed _____ . - ✔✔40%
✔✔What is the minimum acceptable test limit for an ASTM D877 test on mineral oil
used in new 69kV equipment? - ✔✔30kV
✔✔What is the NETA Minimum DC Test Voltage for an Insulation-Resistance test on a
5kV liquid-filled transformer winding? - ✔✔2500
✔✔One advantage DC type motors have over AC types is that: - ✔✔their speed can be
easily varied
✔✔Grounding conductors and bonding jumpers shall not be installed in the same
raceway containing service conductors per NEC. - ✔✔False
✔✔Which test is required for insulating liquid taken from an in-service HV OCB per
NETA standards? - ✔✔ASTM D877
✔✔In which protection scheme does the magnitude and phase angle of the current
flowing at each end of the line determine whether an internal fault exists. - ✔✔Pilot-Wire
✔✔Which of the following ASTM test methods would best measure the neutralization
(acid) number of insulating liquid? - ✔✔D974
✔✔Dielectric Breakdown - ✔✔D877
, ✔✔Dielectric Breakdown kV minimum @ 1mm & 2mm - ✔✔D1816
✔✔Interfacial Tension (mN/m min.) - ✔✔D971
✔✔Neutralization Number (mg KOH/g max.)
Neutralization Number of Less Flammable - ✔✔D974
D664
✔✔Water content - ✔✔D1533
✔✔Power Factor @ 25 C and 100 C - ✔✔D924
✔✔Color Test of insulating liquid - ✔✔D1500
✔✔Visual Condition of insulating liquid - ✔✔D1524
✔✔Specific Gravity - ✔✔D1298
✔✔Fire Point of insulating liquid - ✔✔D92
✔✔What is the expected Maximum Trip Time (in Seconds) for a 480V, 100A molded-
case circuit breaker inverse time test at 300% of Rated Continuous Current? - ✔✔160
✔✔The minimum allowable work space around electrical equipment is _____ inches
wide. - ✔✔30
✔✔Where raceways contain insulated circuit conductors _____ and larger, the
conductors shall be protected from abrasion during and after installation by an identified
fitting providing a smoothly rounded insulating surface. - ✔✔4 AWG
✔✔The power factor of new mineral oil at 100C for equipment rated 69kV and below
should be _____ % or less. - ✔✔0.40
✔✔Power fuse resistance readings on a MV Switch deviate by than 30%. What is the
NETA recommendation? - ✔✔Inspect
✔✔The Angle of Zone of protection of a lightning protection system is approximately: -
✔✔45 degrees
✔✔Concrete-Encased Grounding Electrodes are often referred to as: - ✔✔Ufer Ground
✔✔You are asked to analyze a thermographic image of a single insulated electrical
connection under 60% load, the ambient temperature recorded was 72°F and
