SOS NERC Prep - RELIABILITY EXAM QUESTIONS & ANSWERS
The Reliability Coordinator just informed you of a slow time error correction
L L L L L L L L L L L
which will begin at the top of the next hour. Your EMS system will not let you
L L L L L L L L L L L L L L L L L
change your scheduled frequency. Your Frequency Bias Setting is -100
L L L L L L L L L L
MW/.1Hz. What action should you take?
L L L L L L
A) Increase Net Interchange Schedule by 20 MWs. L L L L L L
B) Inform the Reliability Coordinator that you cannot participate in the time error
L L L L L L L L L L L
correction.
L
C) Decrease Net Interchange Schedule by 20 MWs. L L L L L L
D) Increase Net Interchange Schedule by 10 MWs. - A) Increase Net Interchange
L L L L L L L L L L L
Schedule by 20 MWs.
L L L L
A Balancing Authority has a sudden loss of a large block of load in its area. This loss will
L L L L L L L L L L L L L L L L L L
be seen instantaneously in the change of which of the following values?
L L L L L L L L L L L L
1. Actual Net Interchange L L
2. Scheduled Frequency L
3. Scheduled Net Interchange L L
4. Area Control Error L L
A) 4 only L
B) 1 & 3 L L
C) 1 & 4 L L
D) 3 & 4 - C) 1 & 4
L L L L L L L
Metered Data included in the calculation of ACE are: dynamic schedules, pseudo
L L L L L L L L L L L
ties, actual frequency, and all
L L . L L L L
A) Tie lines readings
L L
B) Generators output L
C) Scheduled frequency indications L L
,D) Transformer load - A) Tie lines readings L L L L L L
Balancing Authority A is currently reading a system frequency of 60.00 Hz. Its Net
L L L L L L L L L L L L L
Actual Interchange is +100 MW and its Net Scheduled Interchange is +200 MW. If
L L L L L L L L L L L L L L
Balancing Authority A's frequency bias setting is 100 MW/0.1 Hz, what is ACE?
L L L L L L L L L L L L L
A) -100
B) 0
C) 10
D) 100 - A) -100 L L L
A Balancing Authority has a Net Interchange Schedule of -250 MWs from 1200 to
L L L L L L L L L L L L L
1600 on a summer day. The Net Interchange Actual for those same hours respectively
L L L L L L L L L L L L L L
were -230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing
L L L L L L L L L L L L L L
Authority's Inadvertent Interchange for the 4-hour period?
L L L L L L L
A) 6 MWs out L L
B) 25 MWs in L L
C) 25 MWs out L L
D) 6 MWs in - B) 25 MWs in
L L L L L L L
For the ACE equation to work properly, dynamic schedules, pseudo ties,
L L L L L L L L L L
frequency, and all
L must be metered.L L L L L
A) Generation
B) Communications
C) Transformers
D) Tie lines - D) Tie lines L L L L L
If the frequency bias setting is set to a less negative value than the frequency response
L L L L L L L L L L L L L L L
of a Balancing Authority and a frequency increase is caused by a sudden loss of load in
L L L L L L L L L L L L L L L L L
an external balancing area, what will be the result?
L L L L L L L L L
A) The ACE will be zero and will take no AGC action
L L L L L L L L L L
B) The ACE will be a negative value and AGC will increase generation
L L L L L L L L L L L
,C) The ACE will be a positive value and AGC will lower generation
L L L L L L L L L L L
D) This will not affect the ACE - B) The ACE will be a negative value and AGC will
L L L L L L L L L L L L L L L L L
increase generation
L L
If the frequency bias setting is less negative than the frequency response of a Balancing
L L L L L L L L L L L L L L
Authority and a frequency decline is caused by a sudden loss of generation in an
L L L L L L L L L L L L L L L
external balancing area, what will be the result?
L L L L L L L L
A) The ACE will be a negative value and AGC will increase generation.
L L L L L L L L L L L
B) This will not affect the ACE.L L L L L
C) The ACE will be a positive value and AGC will lower generation.
L L L L L L L L L L L
D) The ACE will be zero and will take no AGC action. - C) The ACE will be a
L L L L L L L L L L L L L L L L L
positive value and AGC will lower generation.
L L L L L L L
It is the responsibility of which entity/entities to develop, maintain, and implement
L L L L L L L L L L L
load shedding plans?
L L L
A) Transmission Operators and Balancing Authorities L L L L
B) Reliability Coordinator L
C) Load Serving Entities L L
D) Balancing Authority - A) Transmission Operators and Balancing Authorities
L L L L L L L L
A Transmission line is loaded 25% above its SOL. A parallel line is out for routine
L L L L L L L L L L L L L L L
maintenance and can be placed in service in 10 minutes. What is the first step the
L L L L L L L L L L L L L L L L
Operator should take to reduce the line loading?
L L L L L L L L
A) Shed load at the downstream bus.
L L L L L
, B) Open the line. Ld Ld
C) Re-Dispatch Generation. Ld
D) Initiate the restoration of the parallel line. - D) Initiate the restoration of the
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
Ld parallel line. Ld
As a Transmission Operator, you realize that the voltage level is starting to decline
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
in the North West part of the system. Which of the following devices should you,
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
as a Transmission Operator, be able to operate, and/or have another entity operate
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
to raise the voltage level back to normal in the North West part of the system?
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
A) Transformer Underload Tap Changers Ld Ld Ld
B) Shunt Capacitor Banks Ld Ld
C) Generator Reactive Output Ld Ld
D) All answers are correct - D) All answers are correct
Ld Ld Ld Ld Ld Ld Ld Ld Ld
Voltage reduction for load relief should be made on the
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld .
A) Distribution system Ld
B) Entire Interconnection simultaneously
Ld Ld
C) Tie-lines with other Balancing Authority Areas Ld Ld Ld Ld Ld
D) Transmission System - A) Distribution system Ld Ld Ld Ld Ld
Under Frequency Load Shedding (UFLS) is to stabilize the imbalance between
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
generation and load that has been created by a system disturbance. This is
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
accomplished by
Ld . Ld Ld
A) Tripping generation first Ld Ld
B) Voltage reduction on the distribution system.
Ld Ld Ld Ld Ld
C) Shedding all load to arrest frequency Ld Ld Ld Ld Ld
D) Shedding load prior to generation tripping - D) Shedding load prior to
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
generation tripping
Ld Ld
The Reliability Coordinator just informed you of a slow time error correction
L L L L L L L L L L L
which will begin at the top of the next hour. Your EMS system will not let you
L L L L L L L L L L L L L L L L L
change your scheduled frequency. Your Frequency Bias Setting is -100
L L L L L L L L L L
MW/.1Hz. What action should you take?
L L L L L L
A) Increase Net Interchange Schedule by 20 MWs. L L L L L L
B) Inform the Reliability Coordinator that you cannot participate in the time error
L L L L L L L L L L L
correction.
L
C) Decrease Net Interchange Schedule by 20 MWs. L L L L L L
D) Increase Net Interchange Schedule by 10 MWs. - A) Increase Net Interchange
L L L L L L L L L L L
Schedule by 20 MWs.
L L L L
A Balancing Authority has a sudden loss of a large block of load in its area. This loss will
L L L L L L L L L L L L L L L L L L
be seen instantaneously in the change of which of the following values?
L L L L L L L L L L L L
1. Actual Net Interchange L L
2. Scheduled Frequency L
3. Scheduled Net Interchange L L
4. Area Control Error L L
A) 4 only L
B) 1 & 3 L L
C) 1 & 4 L L
D) 3 & 4 - C) 1 & 4
L L L L L L L
Metered Data included in the calculation of ACE are: dynamic schedules, pseudo
L L L L L L L L L L L
ties, actual frequency, and all
L L . L L L L
A) Tie lines readings
L L
B) Generators output L
C) Scheduled frequency indications L L
,D) Transformer load - A) Tie lines readings L L L L L L
Balancing Authority A is currently reading a system frequency of 60.00 Hz. Its Net
L L L L L L L L L L L L L
Actual Interchange is +100 MW and its Net Scheduled Interchange is +200 MW. If
L L L L L L L L L L L L L L
Balancing Authority A's frequency bias setting is 100 MW/0.1 Hz, what is ACE?
L L L L L L L L L L L L L
A) -100
B) 0
C) 10
D) 100 - A) -100 L L L
A Balancing Authority has a Net Interchange Schedule of -250 MWs from 1200 to
L L L L L L L L L L L L L
1600 on a summer day. The Net Interchange Actual for those same hours respectively
L L L L L L L L L L L L L L
were -230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing
L L L L L L L L L L L L L L
Authority's Inadvertent Interchange for the 4-hour period?
L L L L L L L
A) 6 MWs out L L
B) 25 MWs in L L
C) 25 MWs out L L
D) 6 MWs in - B) 25 MWs in
L L L L L L L
For the ACE equation to work properly, dynamic schedules, pseudo ties,
L L L L L L L L L L
frequency, and all
L must be metered.L L L L L
A) Generation
B) Communications
C) Transformers
D) Tie lines - D) Tie lines L L L L L
If the frequency bias setting is set to a less negative value than the frequency response
L L L L L L L L L L L L L L L
of a Balancing Authority and a frequency increase is caused by a sudden loss of load in
L L L L L L L L L L L L L L L L L
an external balancing area, what will be the result?
L L L L L L L L L
A) The ACE will be zero and will take no AGC action
L L L L L L L L L L
B) The ACE will be a negative value and AGC will increase generation
L L L L L L L L L L L
,C) The ACE will be a positive value and AGC will lower generation
L L L L L L L L L L L
D) This will not affect the ACE - B) The ACE will be a negative value and AGC will
L L L L L L L L L L L L L L L L L
increase generation
L L
If the frequency bias setting is less negative than the frequency response of a Balancing
L L L L L L L L L L L L L L
Authority and a frequency decline is caused by a sudden loss of generation in an
L L L L L L L L L L L L L L L
external balancing area, what will be the result?
L L L L L L L L
A) The ACE will be a negative value and AGC will increase generation.
L L L L L L L L L L L
B) This will not affect the ACE.L L L L L
C) The ACE will be a positive value and AGC will lower generation.
L L L L L L L L L L L
D) The ACE will be zero and will take no AGC action. - C) The ACE will be a
L L L L L L L L L L L L L L L L L
positive value and AGC will lower generation.
L L L L L L L
It is the responsibility of which entity/entities to develop, maintain, and implement
L L L L L L L L L L L
load shedding plans?
L L L
A) Transmission Operators and Balancing Authorities L L L L
B) Reliability Coordinator L
C) Load Serving Entities L L
D) Balancing Authority - A) Transmission Operators and Balancing Authorities
L L L L L L L L
A Transmission line is loaded 25% above its SOL. A parallel line is out for routine
L L L L L L L L L L L L L L L
maintenance and can be placed in service in 10 minutes. What is the first step the
L L L L L L L L L L L L L L L L
Operator should take to reduce the line loading?
L L L L L L L L
A) Shed load at the downstream bus.
L L L L L
, B) Open the line. Ld Ld
C) Re-Dispatch Generation. Ld
D) Initiate the restoration of the parallel line. - D) Initiate the restoration of the
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
Ld parallel line. Ld
As a Transmission Operator, you realize that the voltage level is starting to decline
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
in the North West part of the system. Which of the following devices should you,
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
as a Transmission Operator, be able to operate, and/or have another entity operate
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
to raise the voltage level back to normal in the North West part of the system?
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
A) Transformer Underload Tap Changers Ld Ld Ld
B) Shunt Capacitor Banks Ld Ld
C) Generator Reactive Output Ld Ld
D) All answers are correct - D) All answers are correct
Ld Ld Ld Ld Ld Ld Ld Ld Ld
Voltage reduction for load relief should be made on the
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld .
A) Distribution system Ld
B) Entire Interconnection simultaneously
Ld Ld
C) Tie-lines with other Balancing Authority Areas Ld Ld Ld Ld Ld
D) Transmission System - A) Distribution system Ld Ld Ld Ld Ld
Under Frequency Load Shedding (UFLS) is to stabilize the imbalance between
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
generation and load that has been created by a system disturbance. This is
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
accomplished by
Ld . Ld Ld
A) Tripping generation first Ld Ld
B) Voltage reduction on the distribution system.
Ld Ld Ld Ld Ld
C) Shedding all load to arrest frequency Ld Ld Ld Ld Ld
D) Shedding load prior to generation tripping - D) Shedding load prior to
Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld Ld
generation tripping
Ld Ld