NERC System Operator Exam Preparation Latest 2025 Update.
Power equation - Correct Answer P=IV; power (watts)=current (amps) x voltage (volts)
Power equation three phase - Correct Answer Power=Voltage (v) x Current (I) x 1.73 x
Power Factor (PF)
If operating reserve gradually decreases throughout the hour, it's because ___. -
Correct Answer Incorrect load forecast
Operating reserves are made up of ___ and ___. - Correct Answer Regulating Reserves
and Contingency Reserve
What type of reserves are used for AGC? - Correct Answer Regulating
A BA's MSSC is usually its ___. - Correct Answer Largest Generator
Equation to determine speed in RPM of a Generator? - Correct Answer 7200/# of poles
At what frequency will a generator trip on underfrequency? - Correct Answer 57.5 Hz
Why do we have underfrequency tripping? - Correct Answer Protect turbines from
damage
Why does frequency drop faster/is harder to correct, when we have a disturbance when
we have increased wind generation? - Correct Answer Less inertia/governor response
to correct frequency
Frequency above 60 Hz means ___. - Correct Answer Overgenerating
Frequency below 60 Hz means ___. - Correct Answer Undergenerating
Frequency decrease is usually caused by ___. - Correct Answer Loss of generation
A 1% drop in frequency results in ___. - Correct Answer 2% drop in total load; 3% drop
in motor load
,Formula for ACE? - Correct Answer NIa-NIs -10B(Fa-Fs)
Governor response is based on its ___ characteristic. - Correct Answer Droop
5% of 60 Hz= - Correct Answer 3 Hz; most Governor's have 5% droop characteristic
Droop setting is the % required for a generator to run at ___ capacity. - Correct Answer
Full
What is the purpose of a governor deadband? - Correct Answer Minimize wear on
equipment
What % for governor deadband? - Correct Answer +/- .036 Hz
An isochrynous generator setting has ___ droop. - Correct Answer 0%
When are isochryonous generators used? - Correct Answer one unit, during islanding
Is 10% droop or 5% droop more responsive? - Correct Answer 5%
On a classic disturbance chart, what brings frequency from point c to d? - Correct
Answer Contingency Reserve
On a classic disturbance chart, what causes a 'step' change? - Correct Answer Fast-
start generator
What's the primary response to frequency drop? - Correct Answer Governor response
Examples of asynchronous generation? - Correct Answer Solar, wind
What happens to load with increased behind-the-meter generation? - Correct Answer
Peaks later in the day; duck curve
MWs flowing into a BA are - or +? - Correct Answer Negative
, If you lose a 500 MW generator in your BA, your ACE ___. - Correct Answer Decreases
by 500 MW
What part of the ACE equation is always negative? - Correct Answer Frequency Bias
CPS1 says BA has to be ___ for 12 month period, which is evaluated ___. - Correct
Answer ≥100%, monthly
BAAL is a long-term measurement of ___. - Correct Answer ACE
BAAL says Reporting ACE can't exceed the BA's BAAL for more than ___ consecutive
minutes. - Correct Answer 30
BAL-002 deals with ___ and reportable events. - Correct Answer Disturbance Control
Performance
How much Contingency Reserve does a BA have to have? - Correct Answer 100% of
MSSC
A disturbance ≥___% is reportable. - Correct Answer 80% of MSSC
How long does BA have to recover ACE? - Correct Answer 15 minutes
How long does BA have to restore its Contingency Reserves? - Correct Answer 90
minutes
A Reserve Sharing Group is made up of ___. - Correct Answer at least 2 BAs
BA has to recover its ACE back to ___ if it was positive or zero before a disturbance. -
Correct Answer 0
BA has to recover its ACE back to ___ if it was negative before a disturbance. - Correct
Answer pre-disturbance value
BAL-003 says each BA shall implement ___ settings. - Correct Answer Frequency Bias
If B=frequency response, ACE is ___. - Correct Answer unchanged
Power equation - Correct Answer P=IV; power (watts)=current (amps) x voltage (volts)
Power equation three phase - Correct Answer Power=Voltage (v) x Current (I) x 1.73 x
Power Factor (PF)
If operating reserve gradually decreases throughout the hour, it's because ___. -
Correct Answer Incorrect load forecast
Operating reserves are made up of ___ and ___. - Correct Answer Regulating Reserves
and Contingency Reserve
What type of reserves are used for AGC? - Correct Answer Regulating
A BA's MSSC is usually its ___. - Correct Answer Largest Generator
Equation to determine speed in RPM of a Generator? - Correct Answer 7200/# of poles
At what frequency will a generator trip on underfrequency? - Correct Answer 57.5 Hz
Why do we have underfrequency tripping? - Correct Answer Protect turbines from
damage
Why does frequency drop faster/is harder to correct, when we have a disturbance when
we have increased wind generation? - Correct Answer Less inertia/governor response
to correct frequency
Frequency above 60 Hz means ___. - Correct Answer Overgenerating
Frequency below 60 Hz means ___. - Correct Answer Undergenerating
Frequency decrease is usually caused by ___. - Correct Answer Loss of generation
A 1% drop in frequency results in ___. - Correct Answer 2% drop in total load; 3% drop
in motor load
,Formula for ACE? - Correct Answer NIa-NIs -10B(Fa-Fs)
Governor response is based on its ___ characteristic. - Correct Answer Droop
5% of 60 Hz= - Correct Answer 3 Hz; most Governor's have 5% droop characteristic
Droop setting is the % required for a generator to run at ___ capacity. - Correct Answer
Full
What is the purpose of a governor deadband? - Correct Answer Minimize wear on
equipment
What % for governor deadband? - Correct Answer +/- .036 Hz
An isochrynous generator setting has ___ droop. - Correct Answer 0%
When are isochryonous generators used? - Correct Answer one unit, during islanding
Is 10% droop or 5% droop more responsive? - Correct Answer 5%
On a classic disturbance chart, what brings frequency from point c to d? - Correct
Answer Contingency Reserve
On a classic disturbance chart, what causes a 'step' change? - Correct Answer Fast-
start generator
What's the primary response to frequency drop? - Correct Answer Governor response
Examples of asynchronous generation? - Correct Answer Solar, wind
What happens to load with increased behind-the-meter generation? - Correct Answer
Peaks later in the day; duck curve
MWs flowing into a BA are - or +? - Correct Answer Negative
, If you lose a 500 MW generator in your BA, your ACE ___. - Correct Answer Decreases
by 500 MW
What part of the ACE equation is always negative? - Correct Answer Frequency Bias
CPS1 says BA has to be ___ for 12 month period, which is evaluated ___. - Correct
Answer ≥100%, monthly
BAAL is a long-term measurement of ___. - Correct Answer ACE
BAAL says Reporting ACE can't exceed the BA's BAAL for more than ___ consecutive
minutes. - Correct Answer 30
BAL-002 deals with ___ and reportable events. - Correct Answer Disturbance Control
Performance
How much Contingency Reserve does a BA have to have? - Correct Answer 100% of
MSSC
A disturbance ≥___% is reportable. - Correct Answer 80% of MSSC
How long does BA have to recover ACE? - Correct Answer 15 minutes
How long does BA have to restore its Contingency Reserves? - Correct Answer 90
minutes
A Reserve Sharing Group is made up of ___. - Correct Answer at least 2 BAs
BA has to recover its ACE back to ___ if it was positive or zero before a disturbance. -
Correct Answer 0
BA has to recover its ACE back to ___ if it was negative before a disturbance. - Correct
Answer pre-disturbance value
BAL-003 says each BA shall implement ___ settings. - Correct Answer Frequency Bias
If B=frequency response, ACE is ___. - Correct Answer unchanged
