NERC Practice Test, Exam Questions &
Answers
A |transmission |line |is |operating |with |a |voltage |phase |angle |different |of |30 |degrees
|between |the |sending |Vs |and |the |receiving |bus |Vr. |If |the |receiving |end |load |is
|suddenly |increased, |the |voltage |phase |angle |difference |will |be? |- |The |phase |angle
|will |increase. |When |load |is |increased |phase |angle |will |increase.
A load has a power factor of 0.9 lagging. If the load draws 100 MVA, what is the MW
| | | | | | | | | | | | | | | | | |
draw? - 90 pf= mw/mva
| | | | |
The high side of a delta-wye connection transformer is connected to a power system
| | | | | | | | | | | | |
with 199 kV L-G high side voltage. What is the voltage across the delta winding of
| | | | | | | | | | | | | | | |
the transformer? - Vl-l= square root of 3 times Vl-g 1.73x191= 345kV
| | | | | | | | | | | |
If a transmission line is carrying 400 MW and 300 MVAR what is the MVA? - 3- 4-5
| | | | | | | | | | | | | | | | |
triangle 500 MVA
| | |
The prime mover is the component of the generator that creates the rotational force.
| | | | | | | | | | | | |
In a typical coal fired steam generator what component spins the rotor? - Turbine
| | | | | | | | | | | | | |
Reactive reserve response during a disturbance is best obtained from which devise?
| | | | | | | | | | |
- Synchronous condensers
| |
For two identically constructed transmission lines where Line A is 150 miles long and
| | | | | | | | | | | | |
line B is 15 miles long, if both lines are lightly loaded? - A produces more reactive
| | | | | | | | | | | | | | | | |
power than B.
| | |
Lightly loaded transmission lines essentially behave like? - Shunt Capacitors
| | | | | | | | |
You receive an alarm that indicates low oil pressure on an underground transmission
| | | | | | | | | | | |
cable. SCADA shows the pressure is continuing to drop. What is the first step you take
| | | | | | | | | | | | | | | |
to protect the line? - Isolate the line
| | | | | | | |
Computer simulations show that for a 100 MW schedule from Bus A to Bus B, 63% | | | | | | | | | | | | | | |
of the schedule will flow on the scheduled path and the remainder will flow
| | | | | | | | | | | | | |
,on other parallel paths. What is the distribution factor for the scheduled path? - 63%
| | | | | | | | | | | | | |
Which statement best describes how reactive power MVAR power normally flows?
| | | | | | | | | |
- High Voltage to Low Voltage
| | | | | |
Which of the following types of data are BA and RC not required to share with one
| | | | | | | | | | | | | | | |
another? - Generator start up cost
| | | | | |
TOP must develop, maintain, and implement formal policies and procedures to
| | | | | | | | | |
provide for transmission reliability. Which of the following DOES NOT need to be
| | | | | | | | | | | | |
addressed in these policies and procedures? - Planned outages of generation units
| | | | | | | | | | | |
A 1000 MVA rated generator that produces 800 MW and 100 MVAR is best described
| | | | | | | | | | | | | |
as? - Operating in a lagging mode. Inductive system
| | | | | | | | |
Which of the following types of MW load is the most impacted by an intentional
| | | | | | | | | | | | | |
frequency reduction? - Motor
| | | |
Assume there are two 250 mile long transmission lines exporting an excessive
| | | | | | | | | | |
amount of MW from a generation area to a load area. One of the lines suddenly trips
| | | | | | | | | | | | | | | | |
and the area power system collapses within a few seconds. The most likely cause of
| | | | | | | | | | | | | | |
the collapse? - Angle Instability
| | | | |
The phase voltage in a wye-connected load is 277 V. What is the line to line voltage? -
| | | | | | | | | | | | | | | | |
480 V
| |
A simple power system is composed of three lines connecting generation to load.
| | | | | | | | | | | |
Each lines the same impedance, is initially loaded at 200 MW, and has a thermal
| | | | | | | | | | | | | | |
limit of 400 MW. If one line trips, what the loading on the shortest remaining line be
| | | | | | | | | | | | | | | | |
and will the thermal limit either remaining line be violated? - 300 MW and No
| | | | | | | | | | | | | | |
The best prediction of system load is the load forecast tool that uses? - Forecasted
| | | | | | | | | | | | | |
Weather
|
, If the phase angel at an open breaker is equal to 1/10 of a cycle, this is the the same
| | | | | | | | | | | | | | | | | | |
angle as? - 1/10 of 360 so 36
| | | | | | | |
A | tool is used to ensure the power system can respond within | | | | | | | | | |
acceptable limits of N-1 - Contingency Analysis
| | | | | | |
Which of the following activities would not be included in the procedures for
| | | | | | | | | | | |
transmission reliability? - Ancillary service pricing
| | | | | |
The transmission Operator and BA shall provide documentation that operating
| | | | | | | | |
personnel have
| to implement real time actions to ensure the stable and
| | | | | | | | | | |
reliable operation of the BES. - Proper NERC Certification Credential
| | | | | | | | | |
A utility distribution bus has the following customer loads attached. What is the total
| | | | | | | | | | | | |
customer MW load and is the total customer load capacitive or inductive? 5 MW 1
| | | | | | | | | | | | | | |
MVAR & 3 MW 1 MVAR & 2 MW -2 MVAR & 10 MW 3 MVAR - 20
| | | | | | | | | | | | | | | | | |
mw and Inductive
| |
How many MVARs does a 230 kV, 50 MVAR capacitor bank provide when the
| | | | | | | | | | | | |
voltage id 207 kV - Actual MW/ Rated MW ^2 x Capacitor Rating
| | | | | | | | | | | | |
40
You are a system operator and the load forecast is for an all time summer peak
| | | | | | | | | | | | | | |
load day, generations and reactive resources will be tight. Which scheduled job
| | | | | | | | | | | |
would you allow to proceed? - 735 kV shunt reactor maintenance.
| | | | | | | | | | |
A contingency results in the exceedance of an IROL. What could be the result if the
| | | | | | | | | | | | | | |
IROL is allowed to be exceeded longer than T sub v - Interruption of power to a large
| | | | | | | | | | | | | | | | | |
part of the BES
| | | |
Generators have the ability to be used as voltage control devices. If a generator raises| | | | | | | | | | | | | |
its VAR output, the system orator should expect system stage to? - Increase
| | | | | | | | | | | | |
The actual voltage is 362kV on a 345 bus. What is the p.u. voltage? - 1.05
| | | | | | | | | | | | | | |
Answers
A |transmission |line |is |operating |with |a |voltage |phase |angle |different |of |30 |degrees
|between |the |sending |Vs |and |the |receiving |bus |Vr. |If |the |receiving |end |load |is
|suddenly |increased, |the |voltage |phase |angle |difference |will |be? |- |The |phase |angle
|will |increase. |When |load |is |increased |phase |angle |will |increase.
A load has a power factor of 0.9 lagging. If the load draws 100 MVA, what is the MW
| | | | | | | | | | | | | | | | | |
draw? - 90 pf= mw/mva
| | | | |
The high side of a delta-wye connection transformer is connected to a power system
| | | | | | | | | | | | |
with 199 kV L-G high side voltage. What is the voltage across the delta winding of
| | | | | | | | | | | | | | | |
the transformer? - Vl-l= square root of 3 times Vl-g 1.73x191= 345kV
| | | | | | | | | | | |
If a transmission line is carrying 400 MW and 300 MVAR what is the MVA? - 3- 4-5
| | | | | | | | | | | | | | | | |
triangle 500 MVA
| | |
The prime mover is the component of the generator that creates the rotational force.
| | | | | | | | | | | | |
In a typical coal fired steam generator what component spins the rotor? - Turbine
| | | | | | | | | | | | | |
Reactive reserve response during a disturbance is best obtained from which devise?
| | | | | | | | | | |
- Synchronous condensers
| |
For two identically constructed transmission lines where Line A is 150 miles long and
| | | | | | | | | | | | |
line B is 15 miles long, if both lines are lightly loaded? - A produces more reactive
| | | | | | | | | | | | | | | | |
power than B.
| | |
Lightly loaded transmission lines essentially behave like? - Shunt Capacitors
| | | | | | | | |
You receive an alarm that indicates low oil pressure on an underground transmission
| | | | | | | | | | | |
cable. SCADA shows the pressure is continuing to drop. What is the first step you take
| | | | | | | | | | | | | | | |
to protect the line? - Isolate the line
| | | | | | | |
Computer simulations show that for a 100 MW schedule from Bus A to Bus B, 63% | | | | | | | | | | | | | | |
of the schedule will flow on the scheduled path and the remainder will flow
| | | | | | | | | | | | | |
,on other parallel paths. What is the distribution factor for the scheduled path? - 63%
| | | | | | | | | | | | | |
Which statement best describes how reactive power MVAR power normally flows?
| | | | | | | | | |
- High Voltage to Low Voltage
| | | | | |
Which of the following types of data are BA and RC not required to share with one
| | | | | | | | | | | | | | | |
another? - Generator start up cost
| | | | | |
TOP must develop, maintain, and implement formal policies and procedures to
| | | | | | | | | |
provide for transmission reliability. Which of the following DOES NOT need to be
| | | | | | | | | | | | |
addressed in these policies and procedures? - Planned outages of generation units
| | | | | | | | | | | |
A 1000 MVA rated generator that produces 800 MW and 100 MVAR is best described
| | | | | | | | | | | | | |
as? - Operating in a lagging mode. Inductive system
| | | | | | | | |
Which of the following types of MW load is the most impacted by an intentional
| | | | | | | | | | | | | |
frequency reduction? - Motor
| | | |
Assume there are two 250 mile long transmission lines exporting an excessive
| | | | | | | | | | |
amount of MW from a generation area to a load area. One of the lines suddenly trips
| | | | | | | | | | | | | | | | |
and the area power system collapses within a few seconds. The most likely cause of
| | | | | | | | | | | | | | |
the collapse? - Angle Instability
| | | | |
The phase voltage in a wye-connected load is 277 V. What is the line to line voltage? -
| | | | | | | | | | | | | | | | |
480 V
| |
A simple power system is composed of three lines connecting generation to load.
| | | | | | | | | | | |
Each lines the same impedance, is initially loaded at 200 MW, and has a thermal
| | | | | | | | | | | | | | |
limit of 400 MW. If one line trips, what the loading on the shortest remaining line be
| | | | | | | | | | | | | | | | |
and will the thermal limit either remaining line be violated? - 300 MW and No
| | | | | | | | | | | | | | |
The best prediction of system load is the load forecast tool that uses? - Forecasted
| | | | | | | | | | | | | |
Weather
|
, If the phase angel at an open breaker is equal to 1/10 of a cycle, this is the the same
| | | | | | | | | | | | | | | | | | |
angle as? - 1/10 of 360 so 36
| | | | | | | |
A | tool is used to ensure the power system can respond within | | | | | | | | | |
acceptable limits of N-1 - Contingency Analysis
| | | | | | |
Which of the following activities would not be included in the procedures for
| | | | | | | | | | | |
transmission reliability? - Ancillary service pricing
| | | | | |
The transmission Operator and BA shall provide documentation that operating
| | | | | | | | |
personnel have
| to implement real time actions to ensure the stable and
| | | | | | | | | | |
reliable operation of the BES. - Proper NERC Certification Credential
| | | | | | | | | |
A utility distribution bus has the following customer loads attached. What is the total
| | | | | | | | | | | | |
customer MW load and is the total customer load capacitive or inductive? 5 MW 1
| | | | | | | | | | | | | | |
MVAR & 3 MW 1 MVAR & 2 MW -2 MVAR & 10 MW 3 MVAR - 20
| | | | | | | | | | | | | | | | | |
mw and Inductive
| |
How many MVARs does a 230 kV, 50 MVAR capacitor bank provide when the
| | | | | | | | | | | | |
voltage id 207 kV - Actual MW/ Rated MW ^2 x Capacitor Rating
| | | | | | | | | | | | |
40
You are a system operator and the load forecast is for an all time summer peak
| | | | | | | | | | | | | | |
load day, generations and reactive resources will be tight. Which scheduled job
| | | | | | | | | | | |
would you allow to proceed? - 735 kV shunt reactor maintenance.
| | | | | | | | | | |
A contingency results in the exceedance of an IROL. What could be the result if the
| | | | | | | | | | | | | | |
IROL is allowed to be exceeded longer than T sub v - Interruption of power to a large
| | | | | | | | | | | | | | | | | |
part of the BES
| | | |
Generators have the ability to be used as voltage control devices. If a generator raises| | | | | | | | | | | | | |
its VAR output, the system orator should expect system stage to? - Increase
| | | | | | | | | | | | |
The actual voltage is 362kV on a 345 bus. What is the p.u. voltage? - 1.05
| | | | | | | | | | | | | | |
