SOS NERC Prep - RELIABILITY EXAM QUESTIONS & ANSWERS
The Reliability Coordinator just informed you of a slow time error correction which will
x x x x x x x x x x x x x
begin at the top of the next hour. Your EMS system will not let you changeyourscheduled
x x x x x x x x x x x x x x x x x x
frequency. YourFrequencyBiasSettingis -100MW/.1Hz. What action should you
x x x x x x x x x x x x
take?
x
A) IncreaseNet Interchange Scheduleby 20MWs. x x x x x x
B) Informthe ReliabilityCoordinatorthatyoucannot participate inthe timeerror
x x x x x x x x x x x
correction.
x
C) Decrease NetInterchange Scheduleby20MWs. x x x x x x
D) Increase NetInterchange Scheduleby 10MWs. -A)IncreaseNetInterchange x x x x x x x x x x x
Schedule by 20 MWs.
x x x x
A Balancing Authority has a sudden loss ofa large block of loadinits area. This losswillbe
x x x x x x x x x x x x x x x x x x x
seeninstantaneouslyin thechangeofwhich ofthefollowing values?
x x x x x x x x x x x
1. ActualNetInterchange x x
2. ScheduledFrequency x
3. ScheduledNetInterchange x x
4. AreaControlError x x
A) 4 only x
B) 1 & 3 x x
C) 1 & 4 x x
D) 3 & 4 - C)1 & 4
x x x x x x x
Metered Dataincluded in thecalculationofACEare:dynamicschedules, pseudo ties,
x x x x x x x x x x x x
actual frequency, and all
x x . x x x
A) Tielines readings x x
B) Generatorsoutput x
C) Scheduledfrequencyindications x x
,D) Transformer load -A)Tielines readings x x x x x x
Balancing Authority A is currently reading a systemfrequencyof 60.00 Hz. Its Net Actual
x x x x x x x x x x x x x x
Interchange is +100 MW and its Net Scheduled Interchange is +200 MW. If Balancing
x x x x x x x x x x x x x x
Authority A's frequency bias setting is 100 MW/0.1 Hz, what is ACE?
x x x x x x x x x x x x
A) -100
B) 0
C) 10
D) 100 -A) -100 x x x
A Balancing Authority has aNet InterchangeScheduleof -250MWs from1200to 1600
x x x x x x x x x x x x x x
on a summer day. The Net Interchange Actual for those same hours respectively were -
x x x x x x x x x x x x x x x
230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing Authority's
x x x x x x x x x x x x x
Inadvertent Interchange for the 4-hour period?
x x x x x x
A) 6MWs out x x
B) 25MWs in x x
C) 25MWs out x x
D) 6MWs in -B) 25MWs in x x x x x x x
FortheACEequationtowork properly, dynamic schedules, pseudoties,
x x x x x x x x x x
frequency, and all
x must be metered. x x x x x
A) Generation
B) Communications
C) Transformers
D) Tielines - D)Tie lines x x x x x
If the frequency bias setting is set to a less negative value than the frequency responseof a
x x x x x x x x x x x x x x x x x
Balancing Authorityandafrequencyincrease is causedbyasudden loss of load in an
x x x x x x x x x x x x x x x x
external balancing area, what will be the result?
x x x x x x x x
A) TheACE willbezero andwill takeno AGC action x x x x x x x x x x
B) TheACEwillbeanegative value andAGC willincrease generation
x x x x x x x x x x x
,C) TheACE will beapositivevalueand AGC willlowergeneration
x x x x x x x x x x x
D) Thiswill not affect the ACE -B)TheACE willbeanegative valueandAGC will
x x x x x x x x x x x x x x x x x
increase generation
x x
If thefrequencybiassetting is less negative thanthe frequencyresponseofa Balancing
x x x x x x x x x x x x x x
Authority and a frequency decline is caused by a sudden loss of generation in an external
x x x x x x x x x x x x x x x x
balancing area, what will be the result?
x x x x x x x
A) TheACEwillbea negative valueandAGC will increase generation.
x x x x x x x x x x x
B) Thiswillnot affect the ACE. x x x x x
C) TheACE will beapositivevalueand AGC willlowergeneration.
x x x x x x x x x x x
D) TheACE willbezero and will takeno AGC action. -C) TheACEwill bea positive
x x x x x x x x x x x x x x x x x x
value and AGC will lower generation.
x x x x x x
Itisthe responsibilityofwhich entity/entities todevelop, maintain, andimplement load
x x x x x x x x x x x x
shedding plans?
x x
A) TransmissionOperatorsandBalancingAuthorities x x x x
B) ReliabilityCoordinator x
C) Load ServingEntities x x
D) Balancing Authority-A)TransmissionOperatorsandBalancing Authorities x x x x x x x x
A Transmission line is loaded 25%aboveits SOL. A parallel lineisoutforroutine
x x x x x x x x x x x x x x x
maintenance and can be placed in service in 10 minutes. What is the first step the Operator
x x x x x x x x x x x x x x x x x
should take to reduce the line loading?
x x x x x x x
A) Shed load atthe downstreambus. x x x x x
, B) Open the line. d
x d
x
C) Re-Dispatch Generation. d
x
D) Initiate the restoration of the parallel line. - D) Initiate the restoration of the
d
x d
x d
x x d d
x d
x x d d
x d
x d
x x d d
x d
x
x d parallel line. x d
As a Transmission Operator, you realize that the voltage level is starting to decline in
d
x d
x d
x d
x d
x d
x x d d
x d
x d
x x d d
x d
x x d
the North West part of the system. Which of the following devices should you, as a
x d x d x d x d x d x d x d x d x d x d x d x d x d x d x d d
x
Transmission Operator, be able to operate, and/or have another entity operate to
x d x d x d x d x d x d x d x d x d x d x d x d
raise the voltage level back to normal in the North West part of the system?
x d x d x d x d x d x d x d x d x d x d x d x d x d x d x d
A) Transformer Underload Tap Changers d
x d
x d
x
B) Shunt Capacitor Banks d
x d
x
C) Generator Reactive Output d
x d
x
D) All answers are correct - D) All answers are correct
d
x d
x d
x x d d
x d
x d
x d
x d
x
Voltage reduction for load relief should be made on the
x d x d d
x x d x d d
x d
x x d d
x d
x .
A) Distribution system d
x
B) Entire Interconnection simultaneously d
x d
x
C) Tie-lines with other Balancing Authority Areas x d x d d
x d
x d
x
D) Transmission System - A) Distribution system x d d
x d
x d
x d
x
Under Frequency Load Shedding (UFLS) is to stabilize the imbalance between
d
x x d x d d
x d
x d
x d
x d
x d
x d
x
generation and load that has been created by a system disturbance. This is
x d x d x d x d x d x d x d x d x d d
x x d x d x d
accomplished by
x d . x d x d
A) Tripping generation first d
x d
x
B) Voltage reduction on the distribution system. d
x d
x d
x x d x d
C) Shedding all load to arrest frequency d
x d
x x d d
x d
x
D) Shedding load prior to generation tripping - D) Shedding load prior to d
x d
x d
x x d d
x x d d
x d
x d
x d
x d
x
generation tripping
x d x d
The Reliability Coordinator just informed you of a slow time error correction which will
x x x x x x x x x x x x x
begin at the top of the next hour. Your EMS system will not let you changeyourscheduled
x x x x x x x x x x x x x x x x x x
frequency. YourFrequencyBiasSettingis -100MW/.1Hz. What action should you
x x x x x x x x x x x x
take?
x
A) IncreaseNet Interchange Scheduleby 20MWs. x x x x x x
B) Informthe ReliabilityCoordinatorthatyoucannot participate inthe timeerror
x x x x x x x x x x x
correction.
x
C) Decrease NetInterchange Scheduleby20MWs. x x x x x x
D) Increase NetInterchange Scheduleby 10MWs. -A)IncreaseNetInterchange x x x x x x x x x x x
Schedule by 20 MWs.
x x x x
A Balancing Authority has a sudden loss ofa large block of loadinits area. This losswillbe
x x x x x x x x x x x x x x x x x x x
seeninstantaneouslyin thechangeofwhich ofthefollowing values?
x x x x x x x x x x x
1. ActualNetInterchange x x
2. ScheduledFrequency x
3. ScheduledNetInterchange x x
4. AreaControlError x x
A) 4 only x
B) 1 & 3 x x
C) 1 & 4 x x
D) 3 & 4 - C)1 & 4
x x x x x x x
Metered Dataincluded in thecalculationofACEare:dynamicschedules, pseudo ties,
x x x x x x x x x x x x
actual frequency, and all
x x . x x x
A) Tielines readings x x
B) Generatorsoutput x
C) Scheduledfrequencyindications x x
,D) Transformer load -A)Tielines readings x x x x x x
Balancing Authority A is currently reading a systemfrequencyof 60.00 Hz. Its Net Actual
x x x x x x x x x x x x x x
Interchange is +100 MW and its Net Scheduled Interchange is +200 MW. If Balancing
x x x x x x x x x x x x x x
Authority A's frequency bias setting is 100 MW/0.1 Hz, what is ACE?
x x x x x x x x x x x x
A) -100
B) 0
C) 10
D) 100 -A) -100 x x x
A Balancing Authority has aNet InterchangeScheduleof -250MWs from1200to 1600
x x x x x x x x x x x x x x
on a summer day. The Net Interchange Actual for those same hours respectively were -
x x x x x x x x x x x x x x x
230 MW, -275 MW, -250 MW and -270 MW. What was the Balancing Authority's
x x x x x x x x x x x x x
Inadvertent Interchange for the 4-hour period?
x x x x x x
A) 6MWs out x x
B) 25MWs in x x
C) 25MWs out x x
D) 6MWs in -B) 25MWs in x x x x x x x
FortheACEequationtowork properly, dynamic schedules, pseudoties,
x x x x x x x x x x
frequency, and all
x must be metered. x x x x x
A) Generation
B) Communications
C) Transformers
D) Tielines - D)Tie lines x x x x x
If the frequency bias setting is set to a less negative value than the frequency responseof a
x x x x x x x x x x x x x x x x x
Balancing Authorityandafrequencyincrease is causedbyasudden loss of load in an
x x x x x x x x x x x x x x x x
external balancing area, what will be the result?
x x x x x x x x
A) TheACE willbezero andwill takeno AGC action x x x x x x x x x x
B) TheACEwillbeanegative value andAGC willincrease generation
x x x x x x x x x x x
,C) TheACE will beapositivevalueand AGC willlowergeneration
x x x x x x x x x x x
D) Thiswill not affect the ACE -B)TheACE willbeanegative valueandAGC will
x x x x x x x x x x x x x x x x x
increase generation
x x
If thefrequencybiassetting is less negative thanthe frequencyresponseofa Balancing
x x x x x x x x x x x x x x
Authority and a frequency decline is caused by a sudden loss of generation in an external
x x x x x x x x x x x x x x x x
balancing area, what will be the result?
x x x x x x x
A) TheACEwillbea negative valueandAGC will increase generation.
x x x x x x x x x x x
B) Thiswillnot affect the ACE. x x x x x
C) TheACE will beapositivevalueand AGC willlowergeneration.
x x x x x x x x x x x
D) TheACE willbezero and will takeno AGC action. -C) TheACEwill bea positive
x x x x x x x x x x x x x x x x x x
value and AGC will lower generation.
x x x x x x
Itisthe responsibilityofwhich entity/entities todevelop, maintain, andimplement load
x x x x x x x x x x x x
shedding plans?
x x
A) TransmissionOperatorsandBalancingAuthorities x x x x
B) ReliabilityCoordinator x
C) Load ServingEntities x x
D) Balancing Authority-A)TransmissionOperatorsandBalancing Authorities x x x x x x x x
A Transmission line is loaded 25%aboveits SOL. A parallel lineisoutforroutine
x x x x x x x x x x x x x x x
maintenance and can be placed in service in 10 minutes. What is the first step the Operator
x x x x x x x x x x x x x x x x x
should take to reduce the line loading?
x x x x x x x
A) Shed load atthe downstreambus. x x x x x
, B) Open the line. d
x d
x
C) Re-Dispatch Generation. d
x
D) Initiate the restoration of the parallel line. - D) Initiate the restoration of the
d
x d
x d
x x d d
x d
x x d d
x d
x d
x x d d
x d
x
x d parallel line. x d
As a Transmission Operator, you realize that the voltage level is starting to decline in
d
x d
x d
x d
x d
x d
x x d d
x d
x d
x x d d
x d
x x d
the North West part of the system. Which of the following devices should you, as a
x d x d x d x d x d x d x d x d x d x d x d x d x d x d x d d
x
Transmission Operator, be able to operate, and/or have another entity operate to
x d x d x d x d x d x d x d x d x d x d x d x d
raise the voltage level back to normal in the North West part of the system?
x d x d x d x d x d x d x d x d x d x d x d x d x d x d x d
A) Transformer Underload Tap Changers d
x d
x d
x
B) Shunt Capacitor Banks d
x d
x
C) Generator Reactive Output d
x d
x
D) All answers are correct - D) All answers are correct
d
x d
x d
x x d d
x d
x d
x d
x d
x
Voltage reduction for load relief should be made on the
x d x d d
x x d x d d
x d
x x d d
x d
x .
A) Distribution system d
x
B) Entire Interconnection simultaneously d
x d
x
C) Tie-lines with other Balancing Authority Areas x d x d d
x d
x d
x
D) Transmission System - A) Distribution system x d d
x d
x d
x d
x
Under Frequency Load Shedding (UFLS) is to stabilize the imbalance between
d
x x d x d d
x d
x d
x d
x d
x d
x d
x
generation and load that has been created by a system disturbance. This is
x d x d x d x d x d x d x d x d x d d
x x d x d x d
accomplished by
x d . x d x d
A) Tripping generation first d
x d
x
B) Voltage reduction on the distribution system. d
x d
x d
x x d x d
C) Shedding all load to arrest frequency d
x d
x x d d
x d
x
D) Shedding load prior to generation tripping - D) Shedding load prior to d
x d
x d
x x d d
x x d d
x d
x d
x d
x d
x
generation tripping
x d x d
