KNOWN NERC EXAM QUESTIONS: From
Class
A 50 MVA generator is currently producing 40 MWs and 10 MVARs. What are the dynamic
reactive reserves currently on this generator?
a) 50
b) 30
c) 0
d) 20 - ANS d) 20
\A Balancing Authority has a Frequency Bias Setting of -200 MW/.1Hz. What is the
Balancing Authority's Frequency Response for a frequency of 59.95 Hz?
a) 10 MWs
b) 50 MWs
c) 100 MWs
d) 200 MWs - ANS c) 100 MWs
\A Balancing Authority is scheduled to receive 300 MWs from the north and 400 MWs
from the south for hour ending 1300. The north schedule is curtailed starting at 1220 with
a 10-minute ramp. What is the Net Interchange for the hour?
a) 450 MWh
b) 500 MWh
c) 550 MWh
d) 600 MWh - ANS b) 500 MWh
\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 - ANS b) An inaccurate load forecast
\A Balancing Authority receives an Operating Instruction from its Reliability Coordinator.
The Balancing Authority must comply with the Operating Instruction unless:
a) It results in separation from the Interconnection
b) The Balancing Authority disagrees with it
c) Has serious financial implications
d) Results in danger - ANS d) Results in danger
\A contingency results in the exceedence of an IROL. What could be the result if the IROL
is allowed to be exceeded longer than its Tv?
, a) Loss of power to a local area
b) The transmission line could fail
c) Protective relays could fail
d) Interruption of power to a large part of the BES - ANS d) Interruption of power to a
large part of the BES
\A study shows that a single contingency would result in an IROL violation and the
corrective action would require opening a breaker with no SCADA control due to a failed
RTU. What should the system operator do first?
a ) Dispatch field personnel to the breakers substation
b) Shed load near the IROL location
c) Re-dispatch generation to reduce line loading
d) Develop a new response plan for the contingency - ANS a ) Dispatch field personnel to
the breakers substation
\A System Operator is conducting switching operations. When he opens one end of a
transmission line, there is an indication of load loss. What should the operator do?
a) Continue with the switching operation and investigate when complete
b) Suspend the switching operation and verify indications
c) Immediately close the breaker back in
d) File a report to NERC for loss of firm load - ANS b) Suspend the switching operation
and verify indications
\A transaction of 100 MWs is scheduled out of your area at the top of the hour with a
10-minute ramp. You have the following generation available: What combination of
generation would need to be used?
Generator________MWs_________ Curren MWs________ Ramp Capability
1_____________________100 MW______50 MW________________5 MW/min
2____________________100 MW______40 MW________________3 MW/min
3____________________100 MW______50 MW________________1 MW/min
4____________________100 MW______60 MW________________2 MW/min
a) Generators 1, 2 & 3
b) Generators 1, 3 & 4
c) Generators 1, 2 & 4
d) Generators 2, 3 & 4 - ANS c) Generators 1, 2 & 4
\A transmission line in your area is overloaded by 50 MWs. An area generator has a .25
shift factor on the line. How much generation change is required to return the line to its
limit?
a) 50 MWs
b) 100 MWs
c) 200 MWs
Class
A 50 MVA generator is currently producing 40 MWs and 10 MVARs. What are the dynamic
reactive reserves currently on this generator?
a) 50
b) 30
c) 0
d) 20 - ANS d) 20
\A Balancing Authority has a Frequency Bias Setting of -200 MW/.1Hz. What is the
Balancing Authority's Frequency Response for a frequency of 59.95 Hz?
a) 10 MWs
b) 50 MWs
c) 100 MWs
d) 200 MWs - ANS c) 100 MWs
\A Balancing Authority is scheduled to receive 300 MWs from the north and 400 MWs
from the south for hour ending 1300. The north schedule is curtailed starting at 1220 with
a 10-minute ramp. What is the Net Interchange for the hour?
a) 450 MWh
b) 500 MWh
c) 550 MWh
d) 600 MWh - ANS b) 500 MWh
\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 - ANS b) An inaccurate load forecast
\A Balancing Authority receives an Operating Instruction from its Reliability Coordinator.
The Balancing Authority must comply with the Operating Instruction unless:
a) It results in separation from the Interconnection
b) The Balancing Authority disagrees with it
c) Has serious financial implications
d) Results in danger - ANS d) Results in danger
\A contingency results in the exceedence of an IROL. What could be the result if the IROL
is allowed to be exceeded longer than its Tv?
, a) Loss of power to a local area
b) The transmission line could fail
c) Protective relays could fail
d) Interruption of power to a large part of the BES - ANS d) Interruption of power to a
large part of the BES
\A study shows that a single contingency would result in an IROL violation and the
corrective action would require opening a breaker with no SCADA control due to a failed
RTU. What should the system operator do first?
a ) Dispatch field personnel to the breakers substation
b) Shed load near the IROL location
c) Re-dispatch generation to reduce line loading
d) Develop a new response plan for the contingency - ANS a ) Dispatch field personnel to
the breakers substation
\A System Operator is conducting switching operations. When he opens one end of a
transmission line, there is an indication of load loss. What should the operator do?
a) Continue with the switching operation and investigate when complete
b) Suspend the switching operation and verify indications
c) Immediately close the breaker back in
d) File a report to NERC for loss of firm load - ANS b) Suspend the switching operation
and verify indications
\A transaction of 100 MWs is scheduled out of your area at the top of the hour with a
10-minute ramp. You have the following generation available: What combination of
generation would need to be used?
Generator________MWs_________ Curren MWs________ Ramp Capability
1_____________________100 MW______50 MW________________5 MW/min
2____________________100 MW______40 MW________________3 MW/min
3____________________100 MW______50 MW________________1 MW/min
4____________________100 MW______60 MW________________2 MW/min
a) Generators 1, 2 & 3
b) Generators 1, 3 & 4
c) Generators 1, 2 & 4
d) Generators 2, 3 & 4 - ANS c) Generators 1, 2 & 4
\A transmission line in your area is overloaded by 50 MWs. An area generator has a .25
shift factor on the line. How much generation change is required to return the line to its
limit?
a) 50 MWs
b) 100 MWs
c) 200 MWs
