NERC mix question | Actual Questions and Answers Latest
Updated 2026/2027 (Graded A+)
•
The Disturbance Control Standard measures a Balancing Authority's response to a rapid loss of
_____________.
•
demand for energy.
interchange.
ACE.
supply of energy.
- ✔✔supply of energy
•
A Balancing Authority's largest single contingency is a unit rated at 1,000 MW. Which of the following
disturbances would constitute a reportable disturbance for Disturbance Control Performance
evaluation based on the NERC DCS criteria?
•
The loss of a 950 MW generating unit at 100% output.
The loss of 3 generating units totaling 1,300 MW over a period of 3 hours.
The loss of a 750 MW generating unit at 100% output.
The loss of 715 MW of firm load.
- ✔✔The loss of a 950 MW generating unit at 100% output.
•
Balancing Authority informs the Reliability Coordinator that the projected load in a Balancing Area for
the next four hours (over the morning peak) is trending above the available generation that had been
committed for the day. Operating Reserves will be required to be converted into energy to cover the
shortfall. Which Energy Emergency Alert (EEA) level should the RC declare?
•
No EEA should be declared until load shed is expected.
EEA 1
EEA 2
EEA 3
- ✔✔EEA 1
•
A Balancing Authority anticipating an operating capacity or energy emergency shall perform all actions
necessary which includes:
•
Bringing on all available generation
All answers are correct
Preparing to reduce firm load
Postponing equipment maintenance
,- ✔✔All answers are correct
•
As a Transmission Operator, you realize that the voltage level is starting to decline in the North West
part of the system. Which of the following devices should you, as a Transmission Operator, be able to
operate, and/or have another entity operate to raise the voltage level back to normal in the North West
part of the system?
•
Generator Reactive Output
Transformer Underload Tap Changers
All answers are correct
Shunt Capacitor Banks
- ✔✔All answers are correct
•
If a Balancing Authority, Reserve Sharing Group is experiencing conditions where all available
resources are committed to meet firm load, firm transactions, and reserve commitments, what does the
deficient entity need to request their Reliability Coordinator to issue?
•
Energy Emergency Warning
Energy Emergency Alert Level 2
Energy Emergency Alert Level 3
Energy Emergency Alert Level 1
- ✔✔Energy Emergency Alert Level 1
•
One of the functions of underfrequency load shedding is to ______________ within an electrical island
that may have been created by a system disturbance.
•
establish balance between load and interchange balance generation and load
stabilize balance between generators
stabilize the Interconnection
- ✔✔balance generation and load
•
A Balancing Authority that is operating asynchronously (separated from the Interconnection) should
switch its AGC to which mode __________.
•
flat frequency control
tie line bias control
manual control
flat tie-line control
- ✔✔flat frequency control
, •
During a system restoration, what is the system operators priority?
•
Interconnection frequency
Restoration of customer load
Restoration of interchange
Restoration of off-site startup power to generating facilities
- ✔✔Restoration of off-site startup power to generating facilities
•
If multiple lines trip resulting in parallel lines overloading and voltage decreasing, the system operator
should first consider which mitigating actions?
•
Re-dispatch or bring on additional generation
Shed load to reduce the powerflow on the overloaded lines
Open the line breakers to the overloaded lines.
Curtail Interchange Scheduled to the low voltage area
- ✔✔Re-dispatch or bring on additional generation
•
A Balancing Authority foresees or is experiencing conditions where all available resources are
committed to meet firm load, firm transactions. The BA should request which level of the Energy
Emergency Alerts?
•
Energy Emergency Alert Level 1
Energy Emergency Alert Level 4
Energy Emergency Alert Level 2
Energy Emergency Alert Level 3
- ✔✔Energy Emergency Alert Level 1
•
The System Operator experiences a major transmission system disturbance which results in a large
loss of load. Which of the following results is most likely to occur?
•
an increase in system frequency
an increase in system voltage in a wide-area
a decrease in system voltage
a decrease in system frequency
- ✔✔an increase in system frequency
•
A Balancing Authority is assessing its system by reviewing the frequency at locations in its area and
notices a frequency reading at one location varies significantly from the other locations. What might the
Balancing Authority conclude?
Updated 2026/2027 (Graded A+)
•
The Disturbance Control Standard measures a Balancing Authority's response to a rapid loss of
_____________.
•
demand for energy.
interchange.
ACE.
supply of energy.
- ✔✔supply of energy
•
A Balancing Authority's largest single contingency is a unit rated at 1,000 MW. Which of the following
disturbances would constitute a reportable disturbance for Disturbance Control Performance
evaluation based on the NERC DCS criteria?
•
The loss of a 950 MW generating unit at 100% output.
The loss of 3 generating units totaling 1,300 MW over a period of 3 hours.
The loss of a 750 MW generating unit at 100% output.
The loss of 715 MW of firm load.
- ✔✔The loss of a 950 MW generating unit at 100% output.
•
Balancing Authority informs the Reliability Coordinator that the projected load in a Balancing Area for
the next four hours (over the morning peak) is trending above the available generation that had been
committed for the day. Operating Reserves will be required to be converted into energy to cover the
shortfall. Which Energy Emergency Alert (EEA) level should the RC declare?
•
No EEA should be declared until load shed is expected.
EEA 1
EEA 2
EEA 3
- ✔✔EEA 1
•
A Balancing Authority anticipating an operating capacity or energy emergency shall perform all actions
necessary which includes:
•
Bringing on all available generation
All answers are correct
Preparing to reduce firm load
Postponing equipment maintenance
,- ✔✔All answers are correct
•
As a Transmission Operator, you realize that the voltage level is starting to decline in the North West
part of the system. Which of the following devices should you, as a Transmission Operator, be able to
operate, and/or have another entity operate to raise the voltage level back to normal in the North West
part of the system?
•
Generator Reactive Output
Transformer Underload Tap Changers
All answers are correct
Shunt Capacitor Banks
- ✔✔All answers are correct
•
If a Balancing Authority, Reserve Sharing Group is experiencing conditions where all available
resources are committed to meet firm load, firm transactions, and reserve commitments, what does the
deficient entity need to request their Reliability Coordinator to issue?
•
Energy Emergency Warning
Energy Emergency Alert Level 2
Energy Emergency Alert Level 3
Energy Emergency Alert Level 1
- ✔✔Energy Emergency Alert Level 1
•
One of the functions of underfrequency load shedding is to ______________ within an electrical island
that may have been created by a system disturbance.
•
establish balance between load and interchange balance generation and load
stabilize balance between generators
stabilize the Interconnection
- ✔✔balance generation and load
•
A Balancing Authority that is operating asynchronously (separated from the Interconnection) should
switch its AGC to which mode __________.
•
flat frequency control
tie line bias control
manual control
flat tie-line control
- ✔✔flat frequency control
, •
During a system restoration, what is the system operators priority?
•
Interconnection frequency
Restoration of customer load
Restoration of interchange
Restoration of off-site startup power to generating facilities
- ✔✔Restoration of off-site startup power to generating facilities
•
If multiple lines trip resulting in parallel lines overloading and voltage decreasing, the system operator
should first consider which mitigating actions?
•
Re-dispatch or bring on additional generation
Shed load to reduce the powerflow on the overloaded lines
Open the line breakers to the overloaded lines.
Curtail Interchange Scheduled to the low voltage area
- ✔✔Re-dispatch or bring on additional generation
•
A Balancing Authority foresees or is experiencing conditions where all available resources are
committed to meet firm load, firm transactions. The BA should request which level of the Energy
Emergency Alerts?
•
Energy Emergency Alert Level 1
Energy Emergency Alert Level 4
Energy Emergency Alert Level 2
Energy Emergency Alert Level 3
- ✔✔Energy Emergency Alert Level 1
•
The System Operator experiences a major transmission system disturbance which results in a large
loss of load. Which of the following results is most likely to occur?
•
an increase in system frequency
an increase in system voltage in a wide-area
a decrease in system voltage
a decrease in system frequency
- ✔✔an increase in system frequency
•
A Balancing Authority is assessing its system by reviewing the frequency at locations in its area and
notices a frequency reading at one location varies significantly from the other locations. What might the
Balancing Authority conclude?