SOS NERC Prep - RElIABILITY EXAM LATEST 2026-2027
200 QUESTIONS AND 100% Verified ANSWERS
Which equipment should be used first for maintaining or increasing system voltages?
A) Transmission Breakers
B) Shunt Capacitor Banks
C) Shedding unnecessary load
D) Generator Reactive maximum output - answer>>B) Shunt Capacitor Banks
The maximum and minimum voltage, current, frequency, real and reactive power flows on individual equipment
under steady state, short-circuit and transient conditions, as permitted by the equipment owner is ____________.
A) Always changing.
B) The point of collapse
C) The System Operating Limit
D) Equipment Rating - answer>>D) Equipment Rating
There is a 50 MVAR rated capacitor in your system that is currently supplying 45 MVARs to the system. Which of
the following conditions is most likely the cause?
A) The voltage is low in the area of the capacitor.
B) The frequency is above 60.00 Hz.
C) The frequency is below 60.00 Hz.
D) The voltage is high in the area of the capacitor. - answer>>A) The voltage is low in the area of the capacitor.
What would be the expected result at a bus when a long transmission line is placed in service from that bus with
the other end of the line open?
A) Bus voltage will decrease.
B) MVARs would begin flowing into the open- ended line.
C) Nothing.
,D) Bus voltage would increase. - answer>>D) Bus voltage would increase.
What is a contingency?
A) Actual loading on a circuit
B) The unexpected loss of telecommunications
C) The unexpected failure of a system component
D) An operating procedure - answer>>C) The unexpected failure of a system component
Voltage is dropping on a 345 kV transmission system. Which of the following devices can be used to increase
voltage in the 345 kV system?
1. Shunt Capacitor
2. Generator
3. Under-load tap changer increases to raise distribution voltage
4. Shunt Reactor
A) 2 and 4
B) 1, 2 and 3
C) 1 and 2
D) 3 and 3 - answer>>C) 1 and 2
If a Transmission Operator is experiencing an SOL and anticipates having to shed firm load to return to within
limits, which entity (ies) must be notified?
A) All Reliability Coordinators and Balancing Authorities.
B) Its Reliability Coordinator only.
C) All Reliability Coordinators and all Balancing Authorities and Transmission Operators.
D) Its Reliability Coordinator and all other potentially affected Balancing Authorities and Transmission Operators. -
answer>>D) Its Reliability Coordinator and all other potentially affected Balancing Authorities and Transmission
Operators.
A 360 MW Interchange Transaction is curtailed to 0 MWs at 1540. What was the hourly integration for hour
ending 1600?
,A) 240 MWh
B) 0 MWh
C) 120 MWh
D) 360 MWh - answer>>A) 240 MWh
An Arranged Interchange involves the following entities: Source Balancing Authority, Sink Balancing Authority, two
Intermediate Balancing Authorities, two Transmission Service Providers and four PSEs. Which entities must receive
the Arranged Interchange for reliability assessment?
A) Source and Sink Balancing Authorities and the two Transmission Service Providers
B) Source, Intermediate and Sink Balancing Authorities, the two Transmission Service Providers and all four PSEs
C) Source and Sink Balancing Authorities and all four PSEs
D) Source, Intermediate and Sink Balancing Authorities and the two Transmission Service Providers - answer>>D)
Source, Intermediate and Sink Balancing Authorities and the two Transmission Service Providers
In developing and setting up an Arranged Interchange, which of the following would transition the Arranged
Interchange to the Confirmed Interchange status?
A) The TSP's and BA's listed on the Tag have approved the Tag.
B) The BA's and TSP's listed on the Tag have enter the information in their EMS
C) All PSE's listed on the Tag have provided approval.
D) All RC's listed on the tag have provided approval. - answer>>A) The TSP's and BA's listed on the Tag have
approved the Tag.
Which entity is responsible for notifying all involved parties of Interchange that has been transitioned to confirmed
status?
A) The Sink Purchasing-Selling Entity
B) The Reliability Coordinator
C) The Sink Balancing Authority
D) The Source Balancing Authority - answer>>C) The Sink Balancing Authority
, Two Balancing Authorities have arranged for an Interchange Agreement. However, in this deal a High Voltage
Direct Current (HVDC) Transmission Operator is on the scheduling path. What must the Balancing Authorities in
whose area the HVDC tie is controlled do prior to implementing the Interchange Agreement?
A) Coordinate the Interchange Schedule with the Transmission Operator of the HVDC tie.
B) Request the RC to complete the transaction.
C) Nothing needs to be done with the HVDC Transmission Operator because they will rectify any amount of
Megawatt flow as long as it does not exceed their operating limits.
D) Send the HVDC Transmission Operator a copy of the Interchange Agreement after the Schedule has started
ramping. - answer>>A) Coordinate the Interchange Schedule with the Transmission Operator of the HVDC tie.
Which entities may determine the deviation of a Dynamic Schedule constitutes a reliability concern? Also, what
entity must then notify that determination?
A) A Reliability Coordinator or Transmission Operator makes the determination and must notify the Sink Balancing
Authority.
B) Only the Reliability Coordinator may make the determination and must notify the Purchasing-Selling Entity.
C) Only the Transmission Operator may make the determination and must notify the Source Balancing Authority.
D) A Reliability Coordinator or Transmission Operator makes the determination and must notify the Purchasing-
Selling Entity. - answer>>D) A Reliability Coordinator or Transmission Operator makes the determination and must
notify the Purchasing-Selling Entity.
Who is responsible for notifying involved entities when an Arranged Interchange transitions to a Confirmed
Interchange?
A) The Purchase-Selling Entity
B) The Reliability Coordinator
C) The Sink Balancing Authority
D) The Source Balancing Authority - answer>>C) The Sink Balancing Authority
Which of the following Dynamic Schedules must have a modified tag?
A) The Dynamic Schedule is 200 MW and the hourly integrated value is 230 MWH.
200 QUESTIONS AND 100% Verified ANSWERS
Which equipment should be used first for maintaining or increasing system voltages?
A) Transmission Breakers
B) Shunt Capacitor Banks
C) Shedding unnecessary load
D) Generator Reactive maximum output - answer>>B) Shunt Capacitor Banks
The maximum and minimum voltage, current, frequency, real and reactive power flows on individual equipment
under steady state, short-circuit and transient conditions, as permitted by the equipment owner is ____________.
A) Always changing.
B) The point of collapse
C) The System Operating Limit
D) Equipment Rating - answer>>D) Equipment Rating
There is a 50 MVAR rated capacitor in your system that is currently supplying 45 MVARs to the system. Which of
the following conditions is most likely the cause?
A) The voltage is low in the area of the capacitor.
B) The frequency is above 60.00 Hz.
C) The frequency is below 60.00 Hz.
D) The voltage is high in the area of the capacitor. - answer>>A) The voltage is low in the area of the capacitor.
What would be the expected result at a bus when a long transmission line is placed in service from that bus with
the other end of the line open?
A) Bus voltage will decrease.
B) MVARs would begin flowing into the open- ended line.
C) Nothing.
,D) Bus voltage would increase. - answer>>D) Bus voltage would increase.
What is a contingency?
A) Actual loading on a circuit
B) The unexpected loss of telecommunications
C) The unexpected failure of a system component
D) An operating procedure - answer>>C) The unexpected failure of a system component
Voltage is dropping on a 345 kV transmission system. Which of the following devices can be used to increase
voltage in the 345 kV system?
1. Shunt Capacitor
2. Generator
3. Under-load tap changer increases to raise distribution voltage
4. Shunt Reactor
A) 2 and 4
B) 1, 2 and 3
C) 1 and 2
D) 3 and 3 - answer>>C) 1 and 2
If a Transmission Operator is experiencing an SOL and anticipates having to shed firm load to return to within
limits, which entity (ies) must be notified?
A) All Reliability Coordinators and Balancing Authorities.
B) Its Reliability Coordinator only.
C) All Reliability Coordinators and all Balancing Authorities and Transmission Operators.
D) Its Reliability Coordinator and all other potentially affected Balancing Authorities and Transmission Operators. -
answer>>D) Its Reliability Coordinator and all other potentially affected Balancing Authorities and Transmission
Operators.
A 360 MW Interchange Transaction is curtailed to 0 MWs at 1540. What was the hourly integration for hour
ending 1600?
,A) 240 MWh
B) 0 MWh
C) 120 MWh
D) 360 MWh - answer>>A) 240 MWh
An Arranged Interchange involves the following entities: Source Balancing Authority, Sink Balancing Authority, two
Intermediate Balancing Authorities, two Transmission Service Providers and four PSEs. Which entities must receive
the Arranged Interchange for reliability assessment?
A) Source and Sink Balancing Authorities and the two Transmission Service Providers
B) Source, Intermediate and Sink Balancing Authorities, the two Transmission Service Providers and all four PSEs
C) Source and Sink Balancing Authorities and all four PSEs
D) Source, Intermediate and Sink Balancing Authorities and the two Transmission Service Providers - answer>>D)
Source, Intermediate and Sink Balancing Authorities and the two Transmission Service Providers
In developing and setting up an Arranged Interchange, which of the following would transition the Arranged
Interchange to the Confirmed Interchange status?
A) The TSP's and BA's listed on the Tag have approved the Tag.
B) The BA's and TSP's listed on the Tag have enter the information in their EMS
C) All PSE's listed on the Tag have provided approval.
D) All RC's listed on the tag have provided approval. - answer>>A) The TSP's and BA's listed on the Tag have
approved the Tag.
Which entity is responsible for notifying all involved parties of Interchange that has been transitioned to confirmed
status?
A) The Sink Purchasing-Selling Entity
B) The Reliability Coordinator
C) The Sink Balancing Authority
D) The Source Balancing Authority - answer>>C) The Sink Balancing Authority
, Two Balancing Authorities have arranged for an Interchange Agreement. However, in this deal a High Voltage
Direct Current (HVDC) Transmission Operator is on the scheduling path. What must the Balancing Authorities in
whose area the HVDC tie is controlled do prior to implementing the Interchange Agreement?
A) Coordinate the Interchange Schedule with the Transmission Operator of the HVDC tie.
B) Request the RC to complete the transaction.
C) Nothing needs to be done with the HVDC Transmission Operator because they will rectify any amount of
Megawatt flow as long as it does not exceed their operating limits.
D) Send the HVDC Transmission Operator a copy of the Interchange Agreement after the Schedule has started
ramping. - answer>>A) Coordinate the Interchange Schedule with the Transmission Operator of the HVDC tie.
Which entities may determine the deviation of a Dynamic Schedule constitutes a reliability concern? Also, what
entity must then notify that determination?
A) A Reliability Coordinator or Transmission Operator makes the determination and must notify the Sink Balancing
Authority.
B) Only the Reliability Coordinator may make the determination and must notify the Purchasing-Selling Entity.
C) Only the Transmission Operator may make the determination and must notify the Source Balancing Authority.
D) A Reliability Coordinator or Transmission Operator makes the determination and must notify the Purchasing-
Selling Entity. - answer>>D) A Reliability Coordinator or Transmission Operator makes the determination and must
notify the Purchasing-Selling Entity.
Who is responsible for notifying involved entities when an Arranged Interchange transitions to a Confirmed
Interchange?
A) The Purchase-Selling Entity
B) The Reliability Coordinator
C) The Sink Balancing Authority
D) The Source Balancing Authority - answer>>C) The Sink Balancing Authority
Which of the following Dynamic Schedules must have a modified tag?
A) The Dynamic Schedule is 200 MW and the hourly integrated value is 230 MWH.
