SOS NERC PREP RELIABILITY EXAM 2026 NEWEST
ACTUAL EXAM COMPLETE 630 QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100% CORRECT
ANSWERS) /ALREADY GRADED A+
A 345 kV line carrying 1250 MWs trips off line and the reason is unknown. A 230
kV parallel line is now in an SOL and IROL violation. The voltage levels at some
substation buses are 10% below nominal. What can the Transmission Operator do
to return the system back to within established voltage limits ready for the next
contingency?
A) Place shunt reactors in service, if available.
B) Reenergize the tripped line.
C) Send out an appeal for voluntary reductions.
D) Re-dispatch generation, requesting megavar support from each generator,
place all available voltage support equipment on line, and shed load if necessary. -
CORRECT ANSWER ✔✔- D) Re-dispatch generation, requesting megavar support
from each generator, place all available voltage support equipment on line, and
shed load if necessary.
A 345 kV line has a MW flow of 400 and a MVAR flow of 300. The thermal limit of
the line is 600 MVA. Assuming the line voltage is 352 kV, what is the MVA loading
on the line and is the line within its thermal limits?
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,700 MVA/Yes
500 MVA/No
700 MVA/No
500 MVA/Yes - CORRECT ANSWER ✔✔- 500 MVA/Yes
A 345 kV line has a MW flow of 400 and a MVAR flow of 300. The thermal limit of
the line is 600 MVA. Assuming the line voltage is 352 kV, what is the MVA loading
on the line and is the line within its thermal limits?
A) 500 MVA/Yes
B) 700 MVA/Yes
C) 500 MVA/No
D) 700 MVA/No - CORRECT ANSWER ✔✔- A) 500 MVA/Yes
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
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,D) 360 MWh - CORRECT ANSWER ✔✔- A) 240 MWh
A 5% change in voltage will typically lead to what change in the total load
magnitude? (EPRI Chapter 5, number 2)
a. 2%
b. 3 %
c. 5%
d. 10% - CORRECT ANSWER ✔✔- b) 3%
A 50 MVA rated transformer has 40 MW of load. How many MVARs can flow
through the transformer without exceeding the rating?
a. 50 MVAR
b. 40 MVAR
c. 30 MVAR
d. 0 MVAR - CORRECT ANSWER ✔✔- c) 30 MVAR
A 50 MVA transformer has 30 MW flowing into it from the high side. How many
MVARS could flow through it without exceeding limits?
a. 50 MVAR
b. 40 MVAR
c. 30 MVAR
d. 20 MVAR - CORRECT ANSWER ✔✔- b) 40 MVAR
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, A 50 MVA transformer has 30 MW flowing into it from the high-side. How many
MVARS could flow through the transformers without exceeding limits?
a. 20 MVARs
b. 30 MVARs
c. 40 MVARs
d. 50 MVARs - CORRECT ANSWER ✔✔- c) 40 MVARs
A 50 MVA transformer has 30 MW's of load. How many MVARs can flow through
the transformer?
A) 0 MVAR
B) 50 MVAR
C) 40 MVAR
D) 30 MVAR - CORRECT ANSWER ✔✔- C) 40 MVAR
A 500-kV tie line between two Transmission Operators also crosses the boundary
between two Reliability Coordinators. The substation at one end of the line is just
within Reliability Coordinator A's area, while the other end is well within
Reliability Coordinator B's area. The line often has voltage problems due to heavy
unscheduled flow. Which of the following statements is correct?
Reliability Coordinator B is responsible for directing voltage control for the line
terminals.
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ACTUAL EXAM COMPLETE 630 QUESTIONS WITH
DETAILED VERIFIED ANSWERS (100% CORRECT
ANSWERS) /ALREADY GRADED A+
A 345 kV line carrying 1250 MWs trips off line and the reason is unknown. A 230
kV parallel line is now in an SOL and IROL violation. The voltage levels at some
substation buses are 10% below nominal. What can the Transmission Operator do
to return the system back to within established voltage limits ready for the next
contingency?
A) Place shunt reactors in service, if available.
B) Reenergize the tripped line.
C) Send out an appeal for voluntary reductions.
D) Re-dispatch generation, requesting megavar support from each generator,
place all available voltage support equipment on line, and shed load if necessary. -
CORRECT ANSWER ✔✔- D) Re-dispatch generation, requesting megavar support
from each generator, place all available voltage support equipment on line, and
shed load if necessary.
A 345 kV line has a MW flow of 400 and a MVAR flow of 300. The thermal limit of
the line is 600 MVA. Assuming the line voltage is 352 kV, what is the MVA loading
on the line and is the line within its thermal limits?
1|Page
,700 MVA/Yes
500 MVA/No
700 MVA/No
500 MVA/Yes - CORRECT ANSWER ✔✔- 500 MVA/Yes
A 345 kV line has a MW flow of 400 and a MVAR flow of 300. The thermal limit of
the line is 600 MVA. Assuming the line voltage is 352 kV, what is the MVA loading
on the line and is the line within its thermal limits?
A) 500 MVA/Yes
B) 700 MVA/Yes
C) 500 MVA/No
D) 700 MVA/No - CORRECT ANSWER ✔✔- A) 500 MVA/Yes
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
2|Page
,D) 360 MWh - CORRECT ANSWER ✔✔- A) 240 MWh
A 5% change in voltage will typically lead to what change in the total load
magnitude? (EPRI Chapter 5, number 2)
a. 2%
b. 3 %
c. 5%
d. 10% - CORRECT ANSWER ✔✔- b) 3%
A 50 MVA rated transformer has 40 MW of load. How many MVARs can flow
through the transformer without exceeding the rating?
a. 50 MVAR
b. 40 MVAR
c. 30 MVAR
d. 0 MVAR - CORRECT ANSWER ✔✔- c) 30 MVAR
A 50 MVA transformer has 30 MW flowing into it from the high side. How many
MVARS could flow through it without exceeding limits?
a. 50 MVAR
b. 40 MVAR
c. 30 MVAR
d. 20 MVAR - CORRECT ANSWER ✔✔- b) 40 MVAR
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, A 50 MVA transformer has 30 MW flowing into it from the high-side. How many
MVARS could flow through the transformers without exceeding limits?
a. 20 MVARs
b. 30 MVARs
c. 40 MVARs
d. 50 MVARs - CORRECT ANSWER ✔✔- c) 40 MVARs
A 50 MVA transformer has 30 MW's of load. How many MVARs can flow through
the transformer?
A) 0 MVAR
B) 50 MVAR
C) 40 MVAR
D) 30 MVAR - CORRECT ANSWER ✔✔- C) 40 MVAR
A 500-kV tie line between two Transmission Operators also crosses the boundary
between two Reliability Coordinators. The substation at one end of the line is just
within Reliability Coordinator A's area, while the other end is well within
Reliability Coordinator B's area. The line often has voltage problems due to heavy
unscheduled flow. Which of the following statements is correct?
Reliability Coordinator B is responsible for directing voltage control for the line
terminals.
4|Page
