SOS NERC PREP EXAM SCRIPT
COMPREHENSIVE STUDY GUIDE
●● 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
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
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
●● 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.
●● It is the responsibility of which entity/entities to develop, maintain,
and implement load shedding plans?
COMPREHENSIVE STUDY GUIDE
●● 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
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
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
●● 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.
●● It is the responsibility of which entity/entities to develop, maintain,
and implement load shedding plans?
