NERC Reliability Test Bank EXAM LATEST 2026-2027 100
QUESTIONS AND 100% Verified ANSWERS
A System Operator identifies a transmission line that is operating at 100% of its SOL. What should be done?
De-energize the line.
Monitor for necessary action.
Reduce line voltage.
Immediately reduce the loading. - answer>>Monitor for necessary action.
Transmission Operations application: In this case, the transmission line is at its SOL. As long as the System
Operator closely monitors the line and is prepared to take action then no corrective action is needed as long the
limit is not exceeded. The question does not offer information related to how the line is trending or the N-1
impacts.
Balancing Authorities must provide information regarding operating reserves to their Reliability Coordinators.
What type of information must be provided?
Regulating and Contingency Reserves
Spinning and synchronized reserve only
Forecast Peak
Generator Output commitments - answer>>Regulating and Contingency Reserves.
Operating Reserves are that capability above firm system demand required to provide for regulation, load
forecasting error, equipment forced and scheduled outages and local area protection. It consists of
spinning and non-spinning reserve. NERC Standard TOP-003, titled Operational Reliability Data requires the
Balancing Authority to maintain a documented specification for the data necessary for it to perform its analysis
function and Real-time monitoring.
Insulator maintenance must be performed on a 230 kV line. Maintenance personnel inform you that the line must
be de-energized tomorrow to perform the maintenance. In the past, outages of this line on high load days have
resulted in SOL violations on your system. This outage must be coordinated with?
,Only Transmission Operators or Balancing Authorities that participate in the outage.
Only Transmission Operators or Balancing Authorities that are adjacent to your system.
Your Reliability Coordinator and any Transmission Operator or Balancing Authority that may be impacted by the
outage.
Only Reliability Coordinators, Transmission Operators, and Balancing Authorities that request information about
the outage. - answer>>Your Reliability Coordinator and any Transmission Operator or Balancing Authority that
may be impacted by the outage.
NERC Standard TOP-001: Each Transmission Operator shall inform its Reliability Coordinator, known impacted
Balancing Authorities, and known impacted Transmission Operators of its actual or expected operations that result
in, or could result in, an Emergency.
The transmission system must be operated so that instability, uncontrolled separation, or cascading outages will
not occur as a result of the most severe single contingency AND
Specified multiple contingencies
All multiple contingencies
External disturbances
System operating violations - answer>>Specified multiple contingencies.
An 80 mile transmission line from Substation A to Substation B trips. The field crew reports a Zone 2 target at
Substation A and a Zone 1 target at Substation B. Where is the fault anticipated to be?
Outside of the line segment
Within 8 miles of Station B
Midway between A and B
Within 8 miles of Station A - answer>>Within 8 miles of Station B.
Distance relays application: A Zone 1 relay will typically monitor 90% of a line while a Zone 2 relay will typically
monitor 120% of the line. In this problem, a Zone 2 was reported at Station A indicating the fault is up to 120%
away from Station A looking toward Station B. A Zone 1 was reported at Station B indicates the fault is within 90%
,of Station B. Since Station A did not trip on Zone 1 then the fault is past 90% range and closer to Station B and
likely within 10% range of Station B. Therefore, the fault is anticipated to be within 8 miles of Substation B.
Which information should be available to the Reliability Coordinators to have adequate analylsis tools to perform
their responsibilities?
Pre-and post-contingency analysis capabilities (thermal, stability and voltage).
State Estimation.
Wide-area overview displays.
All the above - answer>>All the above.
NERC Standard IRO-002: Each Reliability Coordinator shall have data exchange capabilities with its Balancing
Authorities and Transmission Operators, and with other entities it deems necessary, for it to perform its
Operational Planning Analyses.
A Transmission Operator must monitor critical reliability parameters in real-time such as;
1) Transmission line status
2) Available resources for use
3) Real and Reactive power flows
4) Weather forecast
1 and 3
3 and 4
2 and 3
1 and 2 - answer>>1 and 3.
NERC Standard TOP-001 application of the requirement that each Transmission Operator shall have the necessary
data to perform Real-time Assessments and Real-time Monitoring. Each Transmission Operator shall perform the
following as necessary for determining System Operating Limit (SOL) exceedances within its Transmission
Operator Area...monitor Facilities and the status of Special Protection Systems, and Outside its Transmission
Operator Area, obtain and utilize status, voltages, and flow data for Facilities and the status of Special Protection
Systems.
, Which of the conditions must have an Operating Plan developed by the Transmission Operator?
Switching transmission elements
All the Above
Controlling voltage levels
Responding to IROL - answer>>All the Above.
Each Transmission Operator shall initiate its Operating Plan to mitigate an SOL exceedance identified as part of its
Real-time monitoring or Real-time Assessment. The Operating Plans are a document that identifies a group of
activities that may be used to achieve some goal. Transmission Operators function is more transmission switching,
monitoring and controlling voltage, and real and reactive power flow, and responding to SOL/IROL violations.
Two lines of the same construction are both connected to Bus A and are both open at the other end. Line #2 is
twice as long as Line #1. The voltage at the open end of Line #1 is 3% higher than the voltage at Bus A. What can
you conclude about the voltage at the open end of Line #2?
3% higher than Bus A.
More than 3% lower than Bus A.
More than 3% higher than Bus A.
3% lower than Bus A. - answer>>More than 3% higher than Bus A.
Voltage at the open end of a transmission line will increase due to an effect called Ferranti Rise. If two lines have
the same construction but different lengths, the longer line will produce a higher voltage at the open end
compared to the shorter line. The Ferranti rise effect is a long term overvoltage condition that is associated with
high voltage lines that have their receiving ends open. Overvoltages greater than 10% above nominal can easily
occur. The magnitude of the overvoltage depends on the length of the open-ended line and the strength of the
system tied to the closed-end of the line. EPRI 5.3.2.
The Transmission Operator Area is
All equipment in the Balancing Authority area
QUESTIONS AND 100% Verified ANSWERS
A System Operator identifies a transmission line that is operating at 100% of its SOL. What should be done?
De-energize the line.
Monitor for necessary action.
Reduce line voltage.
Immediately reduce the loading. - answer>>Monitor for necessary action.
Transmission Operations application: In this case, the transmission line is at its SOL. As long as the System
Operator closely monitors the line and is prepared to take action then no corrective action is needed as long the
limit is not exceeded. The question does not offer information related to how the line is trending or the N-1
impacts.
Balancing Authorities must provide information regarding operating reserves to their Reliability Coordinators.
What type of information must be provided?
Regulating and Contingency Reserves
Spinning and synchronized reserve only
Forecast Peak
Generator Output commitments - answer>>Regulating and Contingency Reserves.
Operating Reserves are that capability above firm system demand required to provide for regulation, load
forecasting error, equipment forced and scheduled outages and local area protection. It consists of
spinning and non-spinning reserve. NERC Standard TOP-003, titled Operational Reliability Data requires the
Balancing Authority to maintain a documented specification for the data necessary for it to perform its analysis
function and Real-time monitoring.
Insulator maintenance must be performed on a 230 kV line. Maintenance personnel inform you that the line must
be de-energized tomorrow to perform the maintenance. In the past, outages of this line on high load days have
resulted in SOL violations on your system. This outage must be coordinated with?
,Only Transmission Operators or Balancing Authorities that participate in the outage.
Only Transmission Operators or Balancing Authorities that are adjacent to your system.
Your Reliability Coordinator and any Transmission Operator or Balancing Authority that may be impacted by the
outage.
Only Reliability Coordinators, Transmission Operators, and Balancing Authorities that request information about
the outage. - answer>>Your Reliability Coordinator and any Transmission Operator or Balancing Authority that
may be impacted by the outage.
NERC Standard TOP-001: Each Transmission Operator shall inform its Reliability Coordinator, known impacted
Balancing Authorities, and known impacted Transmission Operators of its actual or expected operations that result
in, or could result in, an Emergency.
The transmission system must be operated so that instability, uncontrolled separation, or cascading outages will
not occur as a result of the most severe single contingency AND
Specified multiple contingencies
All multiple contingencies
External disturbances
System operating violations - answer>>Specified multiple contingencies.
An 80 mile transmission line from Substation A to Substation B trips. The field crew reports a Zone 2 target at
Substation A and a Zone 1 target at Substation B. Where is the fault anticipated to be?
Outside of the line segment
Within 8 miles of Station B
Midway between A and B
Within 8 miles of Station A - answer>>Within 8 miles of Station B.
Distance relays application: A Zone 1 relay will typically monitor 90% of a line while a Zone 2 relay will typically
monitor 120% of the line. In this problem, a Zone 2 was reported at Station A indicating the fault is up to 120%
away from Station A looking toward Station B. A Zone 1 was reported at Station B indicates the fault is within 90%
,of Station B. Since Station A did not trip on Zone 1 then the fault is past 90% range and closer to Station B and
likely within 10% range of Station B. Therefore, the fault is anticipated to be within 8 miles of Substation B.
Which information should be available to the Reliability Coordinators to have adequate analylsis tools to perform
their responsibilities?
Pre-and post-contingency analysis capabilities (thermal, stability and voltage).
State Estimation.
Wide-area overview displays.
All the above - answer>>All the above.
NERC Standard IRO-002: Each Reliability Coordinator shall have data exchange capabilities with its Balancing
Authorities and Transmission Operators, and with other entities it deems necessary, for it to perform its
Operational Planning Analyses.
A Transmission Operator must monitor critical reliability parameters in real-time such as;
1) Transmission line status
2) Available resources for use
3) Real and Reactive power flows
4) Weather forecast
1 and 3
3 and 4
2 and 3
1 and 2 - answer>>1 and 3.
NERC Standard TOP-001 application of the requirement that each Transmission Operator shall have the necessary
data to perform Real-time Assessments and Real-time Monitoring. Each Transmission Operator shall perform the
following as necessary for determining System Operating Limit (SOL) exceedances within its Transmission
Operator Area...monitor Facilities and the status of Special Protection Systems, and Outside its Transmission
Operator Area, obtain and utilize status, voltages, and flow data for Facilities and the status of Special Protection
Systems.
, Which of the conditions must have an Operating Plan developed by the Transmission Operator?
Switching transmission elements
All the Above
Controlling voltage levels
Responding to IROL - answer>>All the Above.
Each Transmission Operator shall initiate its Operating Plan to mitigate an SOL exceedance identified as part of its
Real-time monitoring or Real-time Assessment. The Operating Plans are a document that identifies a group of
activities that may be used to achieve some goal. Transmission Operators function is more transmission switching,
monitoring and controlling voltage, and real and reactive power flow, and responding to SOL/IROL violations.
Two lines of the same construction are both connected to Bus A and are both open at the other end. Line #2 is
twice as long as Line #1. The voltage at the open end of Line #1 is 3% higher than the voltage at Bus A. What can
you conclude about the voltage at the open end of Line #2?
3% higher than Bus A.
More than 3% lower than Bus A.
More than 3% higher than Bus A.
3% lower than Bus A. - answer>>More than 3% higher than Bus A.
Voltage at the open end of a transmission line will increase due to an effect called Ferranti Rise. If two lines have
the same construction but different lengths, the longer line will produce a higher voltage at the open end
compared to the shorter line. The Ferranti rise effect is a long term overvoltage condition that is associated with
high voltage lines that have their receiving ends open. Overvoltages greater than 10% above nominal can easily
occur. The magnitude of the overvoltage depends on the length of the open-ended line and the strength of the
system tied to the closed-end of the line. EPRI 5.3.2.
The Transmission Operator Area is
All equipment in the Balancing Authority area
