NERC 200 ACTUAL EXAM | QUESTIONS AND
ANSWERS | RATED A | 167 Qs & ANSWERS
LATEST 2026/27
1. A generator is capable of producing 250 MW and is currently producing 175
MW with a 5% governor droop. Frequency has suddenly risen by 1.2HZ, what
will be the new generator output?
Decrease 20MW
Decrease 10MW
Increase 10MW
Increase 20MW
2. The net scheduled interchange for a BA area is 150 MW out of its system and
the actual interchange is 185 MW out. The frequency bias setting is 100
MW/0.1 Hz. The scheduled frequency was at 60 Hz and suddenly declined to
59.95 Hz. Which of the following is true about the balancing authorities ACE
and what should the generation do?
ACE is +35 MW; decrease generation
ACE is +15 MW; decrease generation
ACE is -15 MW; increase generation
ACE is -35 MW; increase generation
3. When isolating electrical equipment, you must have a visible open point
usually provided by which device?
relay protection
,disconnect switches
circuit breakers
arresters
,4. If the distribution factor for transmission line 'A-B' were to increase to 30%,
how much of the 200 MW schedule would then flow on this line?
20 MW
40 MW
60 MW
80 MW
5. Why do geomagnetic storms pose a threat to the power system ?
Geomagnetic induced current enter the power system and cause
abnormal operations
Weather events threaten physical power system structures
Geomagnetic storms do not threaten the reliability of the power
system
Geomagnetic induced currents distort the data the SCADA system
reads
6. A governor with a 0% droop is called:
Transient droop
An isochronous governor
Flat frequency control
A blocked governor
7. What is the formula to calculate Available Transfer Capability (ATC)?
ATC = Current Flow + TTC
ATC = TTC - Current Flow
, ATC = TTC + Current Flow
ATC = Current Flow - TTC
8. In a scenario where a sudden load increase occurs, which factor would be
most critical in preventing a rapid drop in frequency, and why?
AVR
Frequency Bias
Inertia
AGC
9. Describe how inductance in a transmission line affects its behavior in terms of
VAR absorption.
Inductance allows the line to dissipate energy as heat.
Inductance causes the transmission line to absorb reactive power
(VARs) from the system.
Inductance increases the line's resistance to current flow.
Inductance enables the line to store energy in the form of electric
fields.
10. If a disturbance causes a 1% drop in frequency in a 15,000 MW power system,
what would be the expected load change?
500 MW
1000 MW
2000 MW
1500 MW
ANSWERS | RATED A | 167 Qs & ANSWERS
LATEST 2026/27
1. A generator is capable of producing 250 MW and is currently producing 175
MW with a 5% governor droop. Frequency has suddenly risen by 1.2HZ, what
will be the new generator output?
Decrease 20MW
Decrease 10MW
Increase 10MW
Increase 20MW
2. The net scheduled interchange for a BA area is 150 MW out of its system and
the actual interchange is 185 MW out. The frequency bias setting is 100
MW/0.1 Hz. The scheduled frequency was at 60 Hz and suddenly declined to
59.95 Hz. Which of the following is true about the balancing authorities ACE
and what should the generation do?
ACE is +35 MW; decrease generation
ACE is +15 MW; decrease generation
ACE is -15 MW; increase generation
ACE is -35 MW; increase generation
3. When isolating electrical equipment, you must have a visible open point
usually provided by which device?
relay protection
,disconnect switches
circuit breakers
arresters
,4. If the distribution factor for transmission line 'A-B' were to increase to 30%,
how much of the 200 MW schedule would then flow on this line?
20 MW
40 MW
60 MW
80 MW
5. Why do geomagnetic storms pose a threat to the power system ?
Geomagnetic induced current enter the power system and cause
abnormal operations
Weather events threaten physical power system structures
Geomagnetic storms do not threaten the reliability of the power
system
Geomagnetic induced currents distort the data the SCADA system
reads
6. A governor with a 0% droop is called:
Transient droop
An isochronous governor
Flat frequency control
A blocked governor
7. What is the formula to calculate Available Transfer Capability (ATC)?
ATC = Current Flow + TTC
ATC = TTC - Current Flow
, ATC = TTC + Current Flow
ATC = Current Flow - TTC
8. In a scenario where a sudden load increase occurs, which factor would be
most critical in preventing a rapid drop in frequency, and why?
AVR
Frequency Bias
Inertia
AGC
9. Describe how inductance in a transmission line affects its behavior in terms of
VAR absorption.
Inductance allows the line to dissipate energy as heat.
Inductance causes the transmission line to absorb reactive power
(VARs) from the system.
Inductance increases the line's resistance to current flow.
Inductance enables the line to store energy in the form of electric
fields.
10. If a disturbance causes a 1% drop in frequency in a 15,000 MW power system,
what would be the expected load change?
500 MW
1000 MW
2000 MW
1500 MW
