KNOWN NERC EXAM QUESTIONS:
FROM CLASS (DETAILED ANSWERS
2025)
, A Balancing Authority notices that Operating Reserve has steadily declined throughout
the hour. What is the most likely cause?
a) Loss of a large generator in the area
b) An inaccurate load forecast
c) Loss of a major transmission line
d) A malfunction of EMS - ANSWERb) An inaccurate load forecast
Balancing Area A notices that the Interconnection frequency is 59.94 Hz and their ACE
is 0. Which of the following could be the cause of this reading?
a) A net under-generation in Balancing Area A
b) A net under-generation in the Interconnection
c) A loss of load in Balancing Area A
d) A loss of load in the Interconnection - ANSWERb) A net under-generation in the
Interconnection
What is the penalty for a Balancing Authority violating the Disturbance Control
Standard?
a) Must carry additional Contingency Reserve
b) Must develop a correction action plan
c) Must re-evaluate and change its Frequency Bias Setting
d) Must increase its Regulating Reserve - ANSWERa) Must carry additional
Contingency Reserve
Your ACE is a large negative value and system frequency is 59.80 Hz. Your AGC
system is pulsing your units down. What should you do?
a) Place AGC in flat frequency control
b) Place AGC in flat tie line control
c) Suspend AGC and investigate
d) Do nothing as this is normal - ANSWERc) Suspend AGC and investigate
When two identical generating units are operated in parallel on governor control, and on
machine has a 5% droop and the other has a 10% droop, the unit with the greater
(10%) governor droop will:
a) Respond less to frequency deviations
b) Respond more to frequency deviations
c) Respond the same to frequency deviations
d) Not adjust for frequency changes - ANSWERa) Respond less to frequency deviations
FROM CLASS (DETAILED ANSWERS
2025)
, A Balancing Authority notices that Operating Reserve has steadily declined throughout
the hour. What is the most likely cause?
a) Loss of a large generator in the area
b) An inaccurate load forecast
c) Loss of a major transmission line
d) A malfunction of EMS - ANSWERb) An inaccurate load forecast
Balancing Area A notices that the Interconnection frequency is 59.94 Hz and their ACE
is 0. Which of the following could be the cause of this reading?
a) A net under-generation in Balancing Area A
b) A net under-generation in the Interconnection
c) A loss of load in Balancing Area A
d) A loss of load in the Interconnection - ANSWERb) A net under-generation in the
Interconnection
What is the penalty for a Balancing Authority violating the Disturbance Control
Standard?
a) Must carry additional Contingency Reserve
b) Must develop a correction action plan
c) Must re-evaluate and change its Frequency Bias Setting
d) Must increase its Regulating Reserve - ANSWERa) Must carry additional
Contingency Reserve
Your ACE is a large negative value and system frequency is 59.80 Hz. Your AGC
system is pulsing your units down. What should you do?
a) Place AGC in flat frequency control
b) Place AGC in flat tie line control
c) Suspend AGC and investigate
d) Do nothing as this is normal - ANSWERc) Suspend AGC and investigate
When two identical generating units are operated in parallel on governor control, and on
machine has a 5% droop and the other has a 10% droop, the unit with the greater
(10%) governor droop will:
a) Respond less to frequency deviations
b) Respond more to frequency deviations
c) Respond the same to frequency deviations
d) Not adjust for frequency changes - ANSWERa) Respond less to frequency deviations
