1|Page
NETA LEVEL 2 EXAMS WITH ACTUAL
CORRECT QUESTIONS AND VERIFIED
DETAILED RATIONALES ANSWERS
LATEST UPDATE ALREADY GRADED
A+
What is the description of the first letter designator for the cooling class of transformers listed here: O
Liquid with a flash point less than or equal to 300*C
What is the description of the first letter designator for the cooling class of transformers listed here: K
Liquid with flash point greater than 300*C
What is the description of the first letter designator for the cooling class of transformers listed here: L
liquid with no measurable flash point
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: N
Natural convection through cooling equipment and windings.
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: F
Forced circulation through cooling equipment, natural convection in windings
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: D
Forced circulation through cooling equipment, directed flow in man windings
What is the description of the THIRD letter designator for the cooling class of transformers listed here:
A
Air
What is the description of the THIRD letterdesignator for the cooling class of transformers listed here:
W
Water
,2|Page
What is the description of the FOURTH letter designator for the cooling class of transformers listed here:
N
Natural convection
What is the description of the FOURTH letter designator for the cooling class of transformers listed
here: F
Forced Circulation
NEC defines CONTINUOUS LOAD as
A load where the maximum current is expected to continue for 3 hours or more.
A downstream 30A fuse will always blow before an upstream 100A fuse.
False
A primary cell is one in which the chemical action is irreversible:
TRUE
A cell or battery designed to deliver its rated capacity once and then be discarded; it is not designed to
be recharged. Primary batteries include alkaline, heavy-duty and general-purpose batteries.
What is the minimum oxygen level before entering a transformer?
23.5% by volume
"Oxygen deficient atmosphere" means
an atmosphere containing less than 19.5 percent oxygen by volume.
"Oxygen enriched atmosphere" means
an atmosphere containing more than 23.5 percent oxygen by volume.
What does an Inverter do?
Changes direct current (DC) to Alternating Current (AC).
What does a Rectifier do?
Converts an Alternating Current (AC) to a Direct Current (DC).
Cells are connected in parallel to give strong current when the external resistance is very low in
comparison to the internal resistance of the cells.
True
Storage batteries for emergency lighting must maintain 85% of charge for 90 minutes.
False
What is the purpose of a line trap?
,3|Page
Substation Communication
-Line Traps prevent transmission of these high frequency signals to unwanted directions without loss of
energy at power frequency.
Contactor coils are present in manual motor starters: True or False
FAlse
What two conditions must be met for a protective relay device 67 to cause tripping?
A-C Directional Overcurrent Relay
Functions on a desired value of a-c over-current flowing in a predetermined direction.
A ________ is used when cables fed from the bottom of a switchboard need to be routed to the top of
the switchboard.
Pull Section
When using a hydrometer, where is the specific gravity of a cell taken?
When using a hydrometer, the specific gravity of a cell should be taken a third of the way down the side
of the cell.
PCB spills of any quantity must be reported to the EPA. True or false
False. spill exceeds 10 pounds of PCBs by weight
The field of a three-phase, squirrel-cage induction motor is located in the rotor.
False
Winding resistance measurements can be made by using a:
Transformer winding resistance measurements are obtained by passing a known DC current through the
winding under test and measuring the voltage drop across each terminal (Ohm's Law). Modern test
equipment for this purposes utilizes a Kelvin bridge to achieve results; you might think of a winding
resistance test set as a very large low-resistance ohmmeter (DLRO).
The minimum operating time of a Buchholz relay is:
The minimum operating time of the relay is 0.1 seconds.
Buchholz relays are ____ actuated.
Gas or Oil actuated
A given 1500kVA transformer has a 4.16kV delta primary winding, a 480Y/277V secondary winding,
and an impedance of 5.75%; what is the maximum secondary fault current of this transformer?
answer=31,377 Amps
Fault Current = Full Load Amps (FLA) / % Impedance (Z)
FLA = (KVA x 1000)/(line to line voltage x 1.732)
, 4|Page
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
Which of the following tests would you perform to verify the integrity of a fiber optic cable?
Optical Time domain reflectomer (OTDR) ?
Overhead service conductors are not permitted to be readily accessible for services not over 600V
nominal. True or False
True
The breaking capacity of a circuit breaker is usually expressed in:
MVA
Which of the following protective functions requires the most energy to trip a circuit breaker? L S I or
G
L long time function
If you have your ground conductor running through your zero-sequence CT with your current carrying
conductors, what will happen?
Ground fault protection won't function
The most accurate method for a ground test is?
3-point (fall - of - potential) method
All approved voltage detectors:
alarms in the proximity of electric fields, it is not necessary to make physical contact with the equipment
being checked. Because it is made of non-conductive materials, it will not conduct electricity and not
cause an arc flash even if contact with energized equipment is made.
What is used to measure resistance?
Wheatstone bridge,
Kelvin double Bridge is used to measure very low resistances (typically less than 1/10 of an ohm).
Surge arresters are _____ devices used to protect electrical insulation in a power system.
voltage limiting
SAE 5, 105K
What is the minimum tensile strength (lbf/in2) of the bolt pictured above?
NETA LEVEL 2 EXAMS WITH ACTUAL
CORRECT QUESTIONS AND VERIFIED
DETAILED RATIONALES ANSWERS
LATEST UPDATE ALREADY GRADED
A+
What is the description of the first letter designator for the cooling class of transformers listed here: O
Liquid with a flash point less than or equal to 300*C
What is the description of the first letter designator for the cooling class of transformers listed here: K
Liquid with flash point greater than 300*C
What is the description of the first letter designator for the cooling class of transformers listed here: L
liquid with no measurable flash point
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: N
Natural convection through cooling equipment and windings.
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: F
Forced circulation through cooling equipment, natural convection in windings
What is the description of the SECOND letter designator for the cooling class of transformers listed
here: D
Forced circulation through cooling equipment, directed flow in man windings
What is the description of the THIRD letter designator for the cooling class of transformers listed here:
A
Air
What is the description of the THIRD letterdesignator for the cooling class of transformers listed here:
W
Water
,2|Page
What is the description of the FOURTH letter designator for the cooling class of transformers listed here:
N
Natural convection
What is the description of the FOURTH letter designator for the cooling class of transformers listed
here: F
Forced Circulation
NEC defines CONTINUOUS LOAD as
A load where the maximum current is expected to continue for 3 hours or more.
A downstream 30A fuse will always blow before an upstream 100A fuse.
False
A primary cell is one in which the chemical action is irreversible:
TRUE
A cell or battery designed to deliver its rated capacity once and then be discarded; it is not designed to
be recharged. Primary batteries include alkaline, heavy-duty and general-purpose batteries.
What is the minimum oxygen level before entering a transformer?
23.5% by volume
"Oxygen deficient atmosphere" means
an atmosphere containing less than 19.5 percent oxygen by volume.
"Oxygen enriched atmosphere" means
an atmosphere containing more than 23.5 percent oxygen by volume.
What does an Inverter do?
Changes direct current (DC) to Alternating Current (AC).
What does a Rectifier do?
Converts an Alternating Current (AC) to a Direct Current (DC).
Cells are connected in parallel to give strong current when the external resistance is very low in
comparison to the internal resistance of the cells.
True
Storage batteries for emergency lighting must maintain 85% of charge for 90 minutes.
False
What is the purpose of a line trap?
,3|Page
Substation Communication
-Line Traps prevent transmission of these high frequency signals to unwanted directions without loss of
energy at power frequency.
Contactor coils are present in manual motor starters: True or False
FAlse
What two conditions must be met for a protective relay device 67 to cause tripping?
A-C Directional Overcurrent Relay
Functions on a desired value of a-c over-current flowing in a predetermined direction.
A ________ is used when cables fed from the bottom of a switchboard need to be routed to the top of
the switchboard.
Pull Section
When using a hydrometer, where is the specific gravity of a cell taken?
When using a hydrometer, the specific gravity of a cell should be taken a third of the way down the side
of the cell.
PCB spills of any quantity must be reported to the EPA. True or false
False. spill exceeds 10 pounds of PCBs by weight
The field of a three-phase, squirrel-cage induction motor is located in the rotor.
False
Winding resistance measurements can be made by using a:
Transformer winding resistance measurements are obtained by passing a known DC current through the
winding under test and measuring the voltage drop across each terminal (Ohm's Law). Modern test
equipment for this purposes utilizes a Kelvin bridge to achieve results; you might think of a winding
resistance test set as a very large low-resistance ohmmeter (DLRO).
The minimum operating time of a Buchholz relay is:
The minimum operating time of the relay is 0.1 seconds.
Buchholz relays are ____ actuated.
Gas or Oil actuated
A given 1500kVA transformer has a 4.16kV delta primary winding, a 480Y/277V secondary winding,
and an impedance of 5.75%; what is the maximum secondary fault current of this transformer?
answer=31,377 Amps
Fault Current = Full Load Amps (FLA) / % Impedance (Z)
FLA = (KVA x 1000)/(line to line voltage x 1.732)
, 4|Page
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
Which of the following tests would you perform to verify the integrity of a fiber optic cable?
Optical Time domain reflectomer (OTDR) ?
Overhead service conductors are not permitted to be readily accessible for services not over 600V
nominal. True or False
True
The breaking capacity of a circuit breaker is usually expressed in:
MVA
Which of the following protective functions requires the most energy to trip a circuit breaker? L S I or
G
L long time function
If you have your ground conductor running through your zero-sequence CT with your current carrying
conductors, what will happen?
Ground fault protection won't function
The most accurate method for a ground test is?
3-point (fall - of - potential) method
All approved voltage detectors:
alarms in the proximity of electric fields, it is not necessary to make physical contact with the equipment
being checked. Because it is made of non-conductive materials, it will not conduct electricity and not
cause an arc flash even if contact with energized equipment is made.
What is used to measure resistance?
Wheatstone bridge,
Kelvin double Bridge is used to measure very low resistances (typically less than 1/10 of an ohm).
Surge arresters are _____ devices used to protect electrical insulation in a power system.
voltage limiting
SAE 5, 105K
What is the minimum tensile strength (lbf/in2) of the bolt pictured above?
