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SOS NERC Prep - RElIABILITY Exam
Questions with Correct Answers | Updated
(100% Correct Answers)
The Reliability Coordinator just informed you of a slow time error
correction which will begin at the top of the next hour. Your EMS
system will not let you change your scheduled frequency. Your
Frequency Bias Setting is -100 MW/.1Hz. What action should you
take?
A) Increase Net Interchange Schedule by 20 MWs.
B) Inform the Reliability Coordinator that you cannot participate in
the time error correction.
C) Decrease Net Interchange Schedule by 20 MWs.
D) Increase Net Interchange Schedule by 10 MWs. Answer: A)
Increase Net Interchange Schedule by 20 MWs.
A Balancing Authority has a sudden loss of a large block of load in
its area. This loss will be seen instantaneously in the change of
which of the following values?
1. Actual Net Interchange
2. Scheduled Frequency
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3. Scheduled Net Interchange
4. Area Control Error
A) 4 only
B) 1 & 3
C) 1 & 4
D) 3 & 4 Answer: C) 1 & 4
Metered Data included in the calculation of ACE are: dynamic
schedules, pseudo ties, actual frequency, and all __________.
A) Tie lines readings
B) Generators output
C) Scheduled frequency indications
D) Transformer load Answer: A) Tie lines readings
Balancing Authority A is currently reading a system frequency of
60.00 Hz. Its Net Actual Interchange is +100 MW and its Net
Scheduled Interchange is +200 MW. If Balancing Authority A's
frequency bias setting is 100 MW/0.1 Hz, what is ACE?
A) -100
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B) 0
C) 10
D) 100 Answer: A) -100
A Balancing Authority has a Net Interchange Schedule of -250 MWs
from 1200 to 1600 on a summer day. The Net Interchange Actual
for those same hours respectively were -230 MW, -275 MW, -250
MW and -270 MW. What was the Balancing Authority's Inadvertent
Interchange for the 4-hour period?
A) 6 MWs out
B) 25 MWs in
C) 25 MWs out
D) 6 MWs in Answer: B) 25 MWs in
For the ACE equation to work properly, dynamic schedules, pseudo
ties, frequency, and all ________________ must be metered.
A) Generation
B) Communications
C) Transformers
D) Tie lines Answer: D) Tie lines
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, 4
If the frequency bias setting is set to a less negative value than the
frequency response of a Balancing Authority and a frequency
increase is caused by a sudden loss of load in an external balancing
area, what will be the result?
A) The ACE will be zero and will take no AGC action
B) The ACE will be a negative value and AGC will increase
generation
C) The ACE will be a positive value and AGC will lower generation
D)This will not affect the ACE Answer: B) The ACE will be a negative
value and AGC will increase generation
If the frequency bias setting is less negative than the frequency
response of a Balancing Authority and a frequency decline is caused
by a sudden loss of generation in an external balancing area, what
will be the result?
A) The ACE will be a negative value and AGC will increase
generation.
B) This will not affect the ACE.
C) The ACE will be a positive value and AGC will lower generation.
D) The ACE will be zero and will take no AGC action. Answer: C)
The ACE will be a positive value and AGC will lower generation.
© 2025 All rights reserved
SOS NERC Prep - RElIABILITY Exam
Questions with Correct Answers | Updated
(100% Correct Answers)
The Reliability Coordinator just informed you of a slow time error
correction which will begin at the top of the next hour. Your EMS
system will not let you change your scheduled frequency. Your
Frequency Bias Setting is -100 MW/.1Hz. What action should you
take?
A) Increase Net Interchange Schedule by 20 MWs.
B) Inform the Reliability Coordinator that you cannot participate in
the time error correction.
C) Decrease Net Interchange Schedule by 20 MWs.
D) Increase Net Interchange Schedule by 10 MWs. Answer: A)
Increase Net Interchange Schedule by 20 MWs.
A Balancing Authority has a sudden loss of a large block of load in
its area. This loss will be seen instantaneously in the change of
which of the following values?
1. Actual Net Interchange
2. Scheduled Frequency
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,2
3. Scheduled Net Interchange
4. Area Control Error
A) 4 only
B) 1 & 3
C) 1 & 4
D) 3 & 4 Answer: C) 1 & 4
Metered Data included in the calculation of ACE are: dynamic
schedules, pseudo ties, actual frequency, and all __________.
A) Tie lines readings
B) Generators output
C) Scheduled frequency indications
D) Transformer load Answer: A) Tie lines readings
Balancing Authority A is currently reading a system frequency of
60.00 Hz. Its Net Actual Interchange is +100 MW and its Net
Scheduled Interchange is +200 MW. If Balancing Authority A's
frequency bias setting is 100 MW/0.1 Hz, what is ACE?
A) -100
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,3
B) 0
C) 10
D) 100 Answer: A) -100
A Balancing Authority has a Net Interchange Schedule of -250 MWs
from 1200 to 1600 on a summer day. The Net Interchange Actual
for those same hours respectively were -230 MW, -275 MW, -250
MW and -270 MW. What was the Balancing Authority's Inadvertent
Interchange for the 4-hour period?
A) 6 MWs out
B) 25 MWs in
C) 25 MWs out
D) 6 MWs in Answer: B) 25 MWs in
For the ACE equation to work properly, dynamic schedules, pseudo
ties, frequency, and all ________________ must be metered.
A) Generation
B) Communications
C) Transformers
D) Tie lines Answer: D) Tie lines
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, 4
If the frequency bias setting is set to a less negative value than the
frequency response of a Balancing Authority and a frequency
increase is caused by a sudden loss of load in an external balancing
area, what will be the result?
A) The ACE will be zero and will take no AGC action
B) The ACE will be a negative value and AGC will increase
generation
C) The ACE will be a positive value and AGC will lower generation
D)This will not affect the ACE Answer: B) The ACE will be a negative
value and AGC will increase generation
If the frequency bias setting is less negative than the frequency
response of a Balancing Authority and a frequency decline is caused
by a sudden loss of generation in an external balancing area, what
will be the result?
A) The ACE will be a negative value and AGC will increase
generation.
B) This will not affect the ACE.
C) The ACE will be a positive value and AGC will lower generation.
D) The ACE will be zero and will take no AGC action. Answer: C)
The ACE will be a positive value and AGC will lower generation.
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