NERC RC Exam Prep Questions With
Well Elaborated Solutions
A Balancing Authority has a normal load of around 8500 MW. Its most severe
single contingency is a 700 MW coal-fired steam unit. At 0810, the ACE value
was at -55 MW when a 600 MW generator in the Balancing Authority's northern
area tripped off line due to a generator differential. This event resulted in a large
negative ACE for the Balancing Authority. What value must ACE return to and in
what time frame to avoid a DCS violation?
A. -55 MW ACE in 15 minutes
B. Zero ACE in 10 minutes
C. -55 MW ACE in 10 minutes
D. Zero ACE in 15 minutes - ANSWER -A. -55 MW ACE in 15 minutes
If a Reserve Sharing Group member has experienced a Reportable Disturbance
condition but does not call for reserve activation from other members, the entire
group is considered to be in a disturbance condition.
A. True
B. False - ANSWER -B. False
Turbine governors arrest Frequency deviations. Of the following, which control
system compares and brings Net Actual Interchange back in line or as close to Net
Scheduled Interchange as possible?
A. Load Response
B. Flat Frequency Control
C. Automatic Generation Control
D. Automatic Voltage Regulation - ANSWER -C. Automatic Generation Control
Automatic Generation Control uses the ACE equation to ________.
A. Minimize Inadvertent Interchange among Balancing Authority areas
,B. Provide frequency support for the Interconnection
C. Both ANSWERs are correct
D. Neither ANSWER is correct - ANSWER -C. Both ANSWERs are correct
Which part of the ACE equation reflects Pseudo-Ties values?
A. Scheduled Net Interchange component, NIS
B. Actual Net Interchange component, NIA
C. Frequency component, FA - FS
D. Pseudo-Ties are not included in the ACE equation. - ANSWER -B. Actual Net
Interchange component, NIA
A Balancing Authority's frequency indication has become erratic and unreliable.
Which AGC mode should the Balancing Authority operate in?
A. Manual Control
B. Flat Frequency Control
C. Tie Line Bias Control
D. Flat Tie Line Control - ANSWER -D. Flat Tie Line Control
Which of the following is required to ensure Balancing Authority operators are
aware of errors associated with data used for calculating Reporting ACE, and how
to mitigate those errors?
A. An Operating Process for identifying and mitigating errors
B. A separate, independent alarm system for ACE data errors
C. A backup Reporting ACE calculation using data from an independent source
D. Monthly training on identifying and mitigating errors - ANSWER -A. An
Operating Process for identifying and mitigating errors
What is the availability requirement per calendar year for frequency metering used
for calculating Reportable ACE?
A. 99.50%
B. 99.00%
,C. 99.95%
D. .995% - ANSWER -C. 99.95%
A Balancing Authority has discovered one tie line meter reading is off by 30 MW,
causing the ACE values to be incorrect. What should be done to temporarily adjust
for the error until the meter can be calibrated or repaired?
A. Take the numbers from the incorrect tie line and insert them into the NIS
portion of the ACE equation
B. Use the IME portion of the equation to adjust for the meter error
C. Change the AGC mode to Flat Frequency Control
D. Change the Frequency Bias part of the ACE equation to reflect the error -
ANSWER -B. Use the IME portion of the equation to adjust for the meter error
Which of the following terms of the ACE equation is not affected by frequency?
A. NIA
B. FA
C. B
D. All terms are affected - ANSWER -C. B
Interchange Schedules are only between adjacent Balancing Authorities, with the
exception of Dynamic Schedules. True or False?
A. True
B. False - ANSWER -A. True
What condition must be met prior to an Arranged Interchange transitioning to an
Implemented status?
A. Energy delivered must be paid for
B. Transaction that are denied have a reason.
C. The Reliability Coordinator provides its approval
, D. Sink Balancing Authority must confirm the transaction status is Confirmed. -
ANSWER -D. Sink Balancing Authority must confirm the transaction status is
Confirmed.
What is the purpose of conducting a reliability assessment for an Arranged
Interchange?
A. Ensure contingency reserves are met
B. Determine the economic benefit
C. Ensure Tag is submitted
D. Determine the capability of supporting the magnitude of the Interchange -
ANSWER -D. Determine the capability of supporting the magnitude of the
Interchange
When an Interchange Transaction is approved, the full amount will travel on the
reserved path per the E-tag.
A. True
B. False - ANSWER -B. False
The communication and coordination of the Interchange process is carried out by
the Interchange Authority. The Interchange Authority is best described as which of
the following?
A. Generation Control of Actual Interchange
B. Energy Management System
C. A computer software program of Electronic Tagging
D. Interconnection Distribution Calculator - ANSWER -C. A computer software
program of Electronic Tagging
When a transaction is approved and becomes Confirmed Interchange, which
entities must be notified?
A. Only the Source and Sink Balancing Authorities and the Reliability Coordinator
Well Elaborated Solutions
A Balancing Authority has a normal load of around 8500 MW. Its most severe
single contingency is a 700 MW coal-fired steam unit. At 0810, the ACE value
was at -55 MW when a 600 MW generator in the Balancing Authority's northern
area tripped off line due to a generator differential. This event resulted in a large
negative ACE for the Balancing Authority. What value must ACE return to and in
what time frame to avoid a DCS violation?
A. -55 MW ACE in 15 minutes
B. Zero ACE in 10 minutes
C. -55 MW ACE in 10 minutes
D. Zero ACE in 15 minutes - ANSWER -A. -55 MW ACE in 15 minutes
If a Reserve Sharing Group member has experienced a Reportable Disturbance
condition but does not call for reserve activation from other members, the entire
group is considered to be in a disturbance condition.
A. True
B. False - ANSWER -B. False
Turbine governors arrest Frequency deviations. Of the following, which control
system compares and brings Net Actual Interchange back in line or as close to Net
Scheduled Interchange as possible?
A. Load Response
B. Flat Frequency Control
C. Automatic Generation Control
D. Automatic Voltage Regulation - ANSWER -C. Automatic Generation Control
Automatic Generation Control uses the ACE equation to ________.
A. Minimize Inadvertent Interchange among Balancing Authority areas
,B. Provide frequency support for the Interconnection
C. Both ANSWERs are correct
D. Neither ANSWER is correct - ANSWER -C. Both ANSWERs are correct
Which part of the ACE equation reflects Pseudo-Ties values?
A. Scheduled Net Interchange component, NIS
B. Actual Net Interchange component, NIA
C. Frequency component, FA - FS
D. Pseudo-Ties are not included in the ACE equation. - ANSWER -B. Actual Net
Interchange component, NIA
A Balancing Authority's frequency indication has become erratic and unreliable.
Which AGC mode should the Balancing Authority operate in?
A. Manual Control
B. Flat Frequency Control
C. Tie Line Bias Control
D. Flat Tie Line Control - ANSWER -D. Flat Tie Line Control
Which of the following is required to ensure Balancing Authority operators are
aware of errors associated with data used for calculating Reporting ACE, and how
to mitigate those errors?
A. An Operating Process for identifying and mitigating errors
B. A separate, independent alarm system for ACE data errors
C. A backup Reporting ACE calculation using data from an independent source
D. Monthly training on identifying and mitigating errors - ANSWER -A. An
Operating Process for identifying and mitigating errors
What is the availability requirement per calendar year for frequency metering used
for calculating Reportable ACE?
A. 99.50%
B. 99.00%
,C. 99.95%
D. .995% - ANSWER -C. 99.95%
A Balancing Authority has discovered one tie line meter reading is off by 30 MW,
causing the ACE values to be incorrect. What should be done to temporarily adjust
for the error until the meter can be calibrated or repaired?
A. Take the numbers from the incorrect tie line and insert them into the NIS
portion of the ACE equation
B. Use the IME portion of the equation to adjust for the meter error
C. Change the AGC mode to Flat Frequency Control
D. Change the Frequency Bias part of the ACE equation to reflect the error -
ANSWER -B. Use the IME portion of the equation to adjust for the meter error
Which of the following terms of the ACE equation is not affected by frequency?
A. NIA
B. FA
C. B
D. All terms are affected - ANSWER -C. B
Interchange Schedules are only between adjacent Balancing Authorities, with the
exception of Dynamic Schedules. True or False?
A. True
B. False - ANSWER -A. True
What condition must be met prior to an Arranged Interchange transitioning to an
Implemented status?
A. Energy delivered must be paid for
B. Transaction that are denied have a reason.
C. The Reliability Coordinator provides its approval
, D. Sink Balancing Authority must confirm the transaction status is Confirmed. -
ANSWER -D. Sink Balancing Authority must confirm the transaction status is
Confirmed.
What is the purpose of conducting a reliability assessment for an Arranged
Interchange?
A. Ensure contingency reserves are met
B. Determine the economic benefit
C. Ensure Tag is submitted
D. Determine the capability of supporting the magnitude of the Interchange -
ANSWER -D. Determine the capability of supporting the magnitude of the
Interchange
When an Interchange Transaction is approved, the full amount will travel on the
reserved path per the E-tag.
A. True
B. False - ANSWER -B. False
The communication and coordination of the Interchange process is carried out by
the Interchange Authority. The Interchange Authority is best described as which of
the following?
A. Generation Control of Actual Interchange
B. Energy Management System
C. A computer software program of Electronic Tagging
D. Interconnection Distribution Calculator - ANSWER -C. A computer software
program of Electronic Tagging
When a transaction is approved and becomes Confirmed Interchange, which
entities must be notified?
A. Only the Source and Sink Balancing Authorities and the Reliability Coordinator
