Page 1 of 125
NERC PREP TEST QUESTION BANK 500 QUESTIONS
AND CORRECT DETAILED SOLUTIONS JUST
RELEASED THIS YEAR
QUESTION: Early in the afternoon, a system operator notices that frequency has dropped to
59.95Hz and his balancing area's ACE is 0. In order to correct the underfrequency condition, the
operator pulses his generators to increase generation. Which statement best describes his
actions?
a. He followed NERC guidelines
b. He violated NERC standards
c. He helped the system
d. He has not impacted the system - ANSWER✔✔b. He violated NERC standards
QUESTION: Voltage of a 345kV transmission line is at 90% of normal. If you energize a capacitor
rated at 100MVar, what will the actual MVars gained?
a. 60 MVars
b. 30 MVars
c. 50 MVars
d. 81 MVars - ANSWER✔✔d. 81 MVars
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QUESTION: A Balancing Area's pre-contingency ACE is -40 MW (below the zero balance point).
At 1525, event time ZERO, the BA looses 800 MW of generation; initial governor action arrests
frequency decay and shows the BA's ACE is now -825 MW. At 1542 the BA's ACE has returned to
-42 MW and the system frequency is 60.001Hz. Assuming that this event is within the DCS
reporting criteria, what other action is the BA required to take?
a.BA must notify the RC that Energy Emergency Alert is required to return ACE to ZERO.
b. No further system operating action is required.
c. The BA recovered more than 80% of its most severe single largest contingency within 15
minutes. No EEA is required.
d. The BA must notify the RC that a unit has been lost and EEA Level 1 is required. -
ANSWER✔✔b. No further system operating action is required.
QUESTION: A tree has been growing under a 230kV transmission line getting closer every year.
As a result of the heavy transfer of megawatts on this particular day, the line sags too close and
flashes over to the tree causing the transmission line to relay out. What type of fault would this
fault be classified as?
a. Overvoltage Fault
b. Ground Fault
c. Differential Fault
d. Positive Sequence Fault - ANSWER✔✔b. Ground Fault
QUESTION: To conform to the CPS requirements, a Balancing Authority must have a
__________________.
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a. CPS1 greater than or equal to 90% or CPS2 greater than or equal to 110%
b. CPS1 greater than or equal to 100% and CPS2 greater than or equal to 90%
c. CPS1 greater than or equal to 200% and CPS2 greater than or equal to 100%
d. CPS1 greater than or equal to 90% and CPS2 greater than or equal to 100% - ANSWER✔✔b.
CPS1 greater than or equal to 100% and CPS2 greater than or equal to 90%
QUESTION: In order to predict the system's near term load pattern, a system operator must
have information including weather forecasts and _____________.
a. Past load patterns
b. Generator overhaul schedules
c. Sufficient metering
d. Generator efficiency ratings - ANSWER✔✔a. Past load patterns
QUESTION: A Balancing Authority has unexpectedly lost 300 MW of generation and has
arranged to receive emergency energy from a neighboring Balancing Authority for 40 minutes,
after which the emergency energy will be replaced by an energy purchase from a PSE. Which of
the following is a correct statement for the operating reserve transaction?
a. No tag is needed because the emergency transaction has duration less than 60 minutes.
b. The PSE must provide a tag for the emergency energy within 60 minutes
c. The Sink Balancing Authority must provide a tag for the emergency energy within 60 minutes
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d. The Source Balancing Authority for the emergency energy must provide a tag within 60
minutes - ANSWER✔✔a. No tag is needed because the emergency transaction has duration less
than 60 minutes.
QUESTION: What group can approve a change in the Disturbance Recovery Period for an
Interconnection?
a. NERC Interconnection Working Group
b. NERC Operating Committee
c. NERC Regional Council
d. NERC Disturbance Analysis Working Group - ANSWER✔✔b. NERC Operating Committee
QUESTION: What is the first thing an operator should do after a relay operation?
a. Check power system stabilizers
b. Notify adjacent Transmission and Balancing areas
c. Check targets and equipment
d. Notify their PSE that the transmission path is out of service - ANSWER✔✔c. Check targets
and equipment
QUESTION: For the ACE equation to work properly, dynamic schedules, pseudo ties, frequency
calculations, and all ________ must be metered.
a. Communications
NERC PREP TEST QUESTION BANK 500 QUESTIONS
AND CORRECT DETAILED SOLUTIONS JUST
RELEASED THIS YEAR
QUESTION: Early in the afternoon, a system operator notices that frequency has dropped to
59.95Hz and his balancing area's ACE is 0. In order to correct the underfrequency condition, the
operator pulses his generators to increase generation. Which statement best describes his
actions?
a. He followed NERC guidelines
b. He violated NERC standards
c. He helped the system
d. He has not impacted the system - ANSWER✔✔b. He violated NERC standards
QUESTION: Voltage of a 345kV transmission line is at 90% of normal. If you energize a capacitor
rated at 100MVar, what will the actual MVars gained?
a. 60 MVars
b. 30 MVars
c. 50 MVars
d. 81 MVars - ANSWER✔✔d. 81 MVars
, Page 2 of 125
QUESTION: A Balancing Area's pre-contingency ACE is -40 MW (below the zero balance point).
At 1525, event time ZERO, the BA looses 800 MW of generation; initial governor action arrests
frequency decay and shows the BA's ACE is now -825 MW. At 1542 the BA's ACE has returned to
-42 MW and the system frequency is 60.001Hz. Assuming that this event is within the DCS
reporting criteria, what other action is the BA required to take?
a.BA must notify the RC that Energy Emergency Alert is required to return ACE to ZERO.
b. No further system operating action is required.
c. The BA recovered more than 80% of its most severe single largest contingency within 15
minutes. No EEA is required.
d. The BA must notify the RC that a unit has been lost and EEA Level 1 is required. -
ANSWER✔✔b. No further system operating action is required.
QUESTION: A tree has been growing under a 230kV transmission line getting closer every year.
As a result of the heavy transfer of megawatts on this particular day, the line sags too close and
flashes over to the tree causing the transmission line to relay out. What type of fault would this
fault be classified as?
a. Overvoltage Fault
b. Ground Fault
c. Differential Fault
d. Positive Sequence Fault - ANSWER✔✔b. Ground Fault
QUESTION: To conform to the CPS requirements, a Balancing Authority must have a
__________________.
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a. CPS1 greater than or equal to 90% or CPS2 greater than or equal to 110%
b. CPS1 greater than or equal to 100% and CPS2 greater than or equal to 90%
c. CPS1 greater than or equal to 200% and CPS2 greater than or equal to 100%
d. CPS1 greater than or equal to 90% and CPS2 greater than or equal to 100% - ANSWER✔✔b.
CPS1 greater than or equal to 100% and CPS2 greater than or equal to 90%
QUESTION: In order to predict the system's near term load pattern, a system operator must
have information including weather forecasts and _____________.
a. Past load patterns
b. Generator overhaul schedules
c. Sufficient metering
d. Generator efficiency ratings - ANSWER✔✔a. Past load patterns
QUESTION: A Balancing Authority has unexpectedly lost 300 MW of generation and has
arranged to receive emergency energy from a neighboring Balancing Authority for 40 minutes,
after which the emergency energy will be replaced by an energy purchase from a PSE. Which of
the following is a correct statement for the operating reserve transaction?
a. No tag is needed because the emergency transaction has duration less than 60 minutes.
b. The PSE must provide a tag for the emergency energy within 60 minutes
c. The Sink Balancing Authority must provide a tag for the emergency energy within 60 minutes
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d. The Source Balancing Authority for the emergency energy must provide a tag within 60
minutes - ANSWER✔✔a. No tag is needed because the emergency transaction has duration less
than 60 minutes.
QUESTION: What group can approve a change in the Disturbance Recovery Period for an
Interconnection?
a. NERC Interconnection Working Group
b. NERC Operating Committee
c. NERC Regional Council
d. NERC Disturbance Analysis Working Group - ANSWER✔✔b. NERC Operating Committee
QUESTION: What is the first thing an operator should do after a relay operation?
a. Check power system stabilizers
b. Notify adjacent Transmission and Balancing areas
c. Check targets and equipment
d. Notify their PSE that the transmission path is out of service - ANSWER✔✔c. Check targets
and equipment
QUESTION: For the ACE equation to work properly, dynamic schedules, pseudo ties, frequency
calculations, and all ________ must be metered.
a. Communications
