Download NERC text questions | Actual Questions and Answers Latest Updated 2025/2026 (Graded A+) and more Exams Electrical Engineering in PDF only on Docsity!
NERC text questions | Actual Questions and Answers Latest Updated
2025 /202 6 (Graded A+)
Operating reserve may be provided by which of the following? A. LTCs B. Capacitor banks C. Voltage regulators D. Interruptible loads - ✔✔D. Interruptible loads Which of the following is the responsibility of a reserve sharing group (RSG)? A. Complying with DCS as if it was a single control area B. Proving regulation service for neighboring RSGs C. Ensuring each control area in the group maintains 50% blackstart capability D. Complying with the control performance standards as if it was a single control area - ✔✔A. Complying with DCS as if it was a single control area Generation is not sufficient to meet load, the control area is importing heavily, and voltage is decaying, which of the following actions should be taken by the operator? A. Shed load B. Correct schedule deviation C. Use the Interconnection Hotline D. Schedule interchange transaction - ✔✔A. Shed load What measures power flow data between control areas? A. OASIS B. Interchange C. Transactions D. Tie-Line metering - ✔✔D. Tie-Line metering
Transmission line removal as a voltage control can be used if: A. Loop flow remains high B. Reactive equipment is available C. Reliability stays at acceptable levels D. Synchronous condensers are off the line - ✔✔C. Reliability stays at acceptable levels Control Area A is generating and sending Control Area B a schedule. Both control areas should verify all of the following EXCEPT: A. Magnitude (MW) B. Ramp rate C. Price D. Start/stop times - ✔✔C. Price The AGC control mode that is normally used for system operation is: A. Flat Tie Mode B. Flat Frequency Mode C. Frequency Bias Mode D. Tie Line Bias Mode - ✔✔D. Tie Line Bias Mode There has been a wide-area disturbance. The transfers through the system have increased and there is a possibility that loss of one major tie line would cause corresponding loading and voltage deviations. Having system resources available, the security coordinator should: A. Increase generation to reduce flows across the ties B. Implement schedule changes across the hour C. Implement a voltage reduction plan D. Advise the supervisor - ✔✔A. Increase generation to reduce flows across the ties When referring to transmission lines of an interconnected network, neighboring systems should use: A. Own line identifiers and ratings
A. Interchange schedules B. Capacitor banks C. Reactors D. LTCs - ✔✔A. Interchange schedules Per Policy 4, 4A, In order to predict the system's near term load pattern, a system operator must have information including weather forecasts and: A. Sufficient metering B. Past load patterns C. Projected load patterns D. Generator overhaul schedules - ✔✔B. Past load patterns All of the following electric system security data are to be updated at least every 10 minutes EXCEPT: A. Operating reserve B. Control area demand C. Area control area frequency D. Forecast changes on equipment status - ✔✔D. Forecast changes on equipment status Security Coordinator A requests Reliability Coordinator B to curtail a transaction from B to C. The Reliability Coordinator B should do which of the following: A. Ask A to redispatch B. Honor the request C. Implement voltage reduction D. Coordinate with regional office - ✔✔B. Honor the request The NERC certification examination program should comply with the standards established by which of the following? A. National Commission for Certifying Agencies B. American National Standards Institute C. American Society of Testing Materials
D. National Bureau of Standards - ✔✔A. National Commission for Certifying Agencies System operator training program criteria should be based upon all of the following EXCEPT: A. FERC criteria B. Regional council policies C. NERC operating policies D. Regulatory requirements - ✔✔A. FERC criteria Which of the following actions is used to prevent a voltage collapse when reactive resources are insufficient? A. Lower transmission voltage regulator settings B. Implement load reduction C. Offset scheduled frequency D. Reduce generator output - ✔✔B. Implement load reduction NERC policies define the term "interchange" as: A. Demand that can be interrupted by direct action of the supplying system's system operator B. The amount of electric power delivered or required at specific points on the system C. Energy transfers across control area boundaries D. A plan or arrangement for transaction - ✔✔C. Energy transfers across control area boundaries Emergency actions for immediately responding to a sudden generation capacity deficiency may include: A. Purchasing economic energy B. Starting another fossil fuel unit C. Scheduling available emergency assistance and implementing load shedding D. Postponing equipment maintenance on units if it will derate the unit by 10% or more - ✔✔C. Scheduling available emergency assistance and implementing load shedding
C. 12 months D. 0 months - ✔✔D. 0 months As a general rule (preference not requirement), digital data should be sampled every : A. 2 seconds B. 4 seconds C. 6 seconds D. 8 seconds - ✔✔B. 4 seconds Results of the NERC hotline test shall be reported to the NERC operations committee each: A. Day B. Month C. Quarter D. Year - ✔✔C. Quarter Under normal conditions, what is the primary reason AGC equipment should remain in-service? A. To regulate control area interties B. To regulate non-spinning reserve C. To adjust for poor load forecasting D. To provide inadveretent payback - ✔✔A. To regulate control area interties Studies have indicated that for a voltage reduction of 5%, non-motor loads, on average, will decrease by what percentage? A. 5% B. 6.5% C. 8% D. 9.5% - ✔✔B. 6.5% What is a capacity benefit margin?
A. The unloaded and available on line generation capability B. Transmission capacity set aside to back up the loss of generation C. The amount of installed generation above the systems peak demand forecast D. The amount of quick start generation capacity - ✔✔B. Transmission capacity set aside to back up the loss of generation Electric utilities must report major losses of firm system loads to which one of the following entities? A. FERC B. RCMP C. DOE D. EEI - ✔✔C. DOE SMD (solar magnetic disturbance) may cause which of the following? A. Relay operation B. Transformer overheating C. Transmission line de-rating D. Frequency excursions - ✔✔B. Transformer overheating (most likely primay result) Area Interchange Error Surveys are conducted to improve which of the following? A. Voltage stability B. Frequency regulation C. Economy of operation D. Line overloads - ✔✔B. Frequency regulation There is an inadvertent accumulation of +240 MWh (over generation) that should be used to schedule exchange with a neighboring control area. If 50% is on peak, which schedule will work? A. 10 MW received hour ending 1300 Saturday through hour ending 1200 Sunday (CST) B. 10 MW received all day Wednesday
A substation and all the transmission lines into the substation suddenly indicate de-energized on the SCADA. The breakers at this substation indicate closed, BUT the remote line breakers indicate open. What would be the most probable cause for this activity? A. Communication path failure with the substation RTU B. The power supply for the RTU has failed C. A breaker failed to trip (at the now de-energized substation), initiating back-up relay operation. D. A technician caused a computer monitoring glitch - ✔✔A. Communication path failure with the substation RTU Status of power system equipment must be provided to system operators, enabling them to: A. Detect abnormal conditions and take appropriate action B. Report unusual voltage excursions C. Determine equipment maintenance schedules D. Plan for transformer load changes - ✔✔A. Detect abnormal conditions and take appropriate action The primary purpose for a special protection scheme (SPS) or remedial action scheme (RAS) is to A. Ensure proper breaker tripping and reclosing B. Isolate electrical faults C. Balance load and generation after a loss of resources (preserving stability) D. Provide additional load information to the operator - ✔✔C. Balance load and generation after a loss of resources (preserving stability) An alarm is received from a substation indicating relay trouble on a 230/1 15 - KV autotransformer. What would be a minimum typical compliment of relays associated with this type of transformer? A. Undercurrent, over voltage, and over frequency B. Overcurrent, differential, and sudden pressure C. Impedance, ground, and under frequency D. Overvoltage, over current, and under frequency - ✔✔B. Overcurrent, differential, and sudden pressure
When must changes or additions to protective relay schemes on interconnected transmission lines be coordinated with neighboring systems A. After the line relays operate due to suspect causes B. Before the neighboring system is affected C. When the line exceeds its thermal operating limit D. During heavy load periods - ✔✔B. Before the neighboring system is affected Unless agreed to otherwise an interchange transaction shall be submitted to all control areas on the scheduling path no later than: A. 10 minutes before the transaction begins B. 20 minutes before the transaction begins C. 40 minutes before the transaction begins D. 60 minutes before the transaction begins - ✔✔B. 20 minutes before the transaction begins Control areas that are parties to an interchange schedule shall be known to each other:
- Before confirming a schedule
- Before implementing a schedule
- After completing a schedule [Select from answers below] A. 1 only B.2 only C.1 and 3 only D. 1 and 2 only - ✔✔D. 1 and 2 only A system is part of a reserve sharing group and the system operator is obligated to carry an amount of operating reserve equal to 5% of on-line hydro generation and 7% of on-line thermal generation. Present generation is 4,600 MW, comprised of 3,600 MW hydro and 1,000 MW thermal. Which of the following is true? A. The control area operating reserve requirements is 260 MW B. The spinning reserve component of operating reserve shall be at least 50% of the respective reserve requirement C. It is acceptable to consider an interruptible load of 120 MW as spinning reserve
System frequency is slightly less than schedule, this is an indicator to the System Operator that: A. Load is responding slower than generation B. A generator has tripped or is in trouble C. Load is greater than generation D. A generator has just come on line - ✔✔C. Load is greater than generation A system is supplying 4,000 MW of load. The Area Control Error is at zero when a 1,100 MW unit loaded at 1,000 MW is lost. The frequency begins to decline from 60 Hz. The loss of this unit has depleted the 250 MW operating reserve requirement. To restore the system to the predisturbance condition, the system operator must load how much generation? A. 578 MW B. 750 MW C. 1,000 MW D. 1,125 MW - ✔✔C. 1,000 MW The actual amount of load pick-up will be 1000 - 250=750:but NERC answer desires "C". In reality only 750 MW gen must be loaded if 250 MW reserve capacity has been converted to energy; Approx. 250 MW of reserve capacity must also be stored. A 500 - KV transmission line is supplying 20 amps of load. What is the calculated MVA supplied by the line? A. 10 MVA B. 100 MVA C. 1,000 MVA D. 10,000 MVA - ✔✔A. 10 MVA Assuming unity power factor (zero MVAR), and a 3 - phase line, MVA=(kV x amps x 1.73 = 17.3 MVA Responding to operating security limit violations is necessary most frequently when: A. Violations occur or are expected to occur B. There is a reduction to transaction required C. It may lead to voltage collapse
D. It will cause cascading outages - ✔✔A. Violations occur or are expected to occur Prompt action shall be taken to restore reactive resources if they: A. Drop below acceptable levels B. Are removed from service via a relay action C. Are removed from service for maintenance D. Are needed for immediate voltage control - ✔✔A. Drop below acceptable levels To use reactive resources effectively when contingencies occur, they shall be A. Dispersed B. Concentrated C. Purchased D. Regularly tested - ✔✔A. Dispersed Which of the following services provided to end users does the purchasing-selling entity need to demonstrate to the host Control Area?
- Dispatching services
- Interchange accounting services
- Generation services
- Transmission services [Select from answers below] A. 1 and 2 B. 2 and 4 C. 2 and 3 D. 3 and 4 - ✔✔D. 3 and 4 For a loss of generation, which entity is required to initiate a termination notification of an implemented interchange transaction? A. Purchasing-selling entity B. Transmission provider
After load forecast is completed, the generating units should be assigned by unit commitment to meet forecasted load, ... [select the answer to most correctly complete the statement] A. And reserve obligation B. Reserve obligation, and energy transfers C. Losses, reserve obligation, and energy transfers D. Losses, reserve obligation, energy transfers, and entity requests - ✔✔A. And reserve obligation At what frequency does steam turbine damage be likely to occur without time duration and the unit needing to be tripped? A. 57.00 Hz B. 57.50 Hz C. 58.00 Hz D. 58.05 Hz - ✔✔B. 57.50 Hz When possible, a system operator should try to use which of the following to energize high voltage transmission lines? A. The strongest source B. The largest circuit breaker (physical size implied) C. The weakest source D. A generating station - ✔✔A. The strongest source A decision needs to be made within one minute after loss of a generating unit as to the need for emergency assistance. What else should be occurring during this time? A. A call to executive management B. Notification of all control areas C. Trend toward 60 Hz D. Isolation of unit - ✔✔C. Trend toward 60 Hz How is (transmission) voltage reduction implemented to obtain load relief? A. Changing transformer taps
B. Increasing line ampere flow C. Providing a potential difference D. By appealing to the public - ✔✔A. Changing transformer taps What measurement is used by a member of a reserve sharing group to monitor operating reserve availability and actual response? A. Control performance criteria B. Difference between actual interchange and scheduled interchange C. Difference between actual frequency and scheduled frequency D. Ready reserve - ✔✔A. Control performance criteria At what point is a reserve sharing group considered to be in a disturbance condition? A. When there are no reserves B. Upon frequency decline C. When a group member is in a disturbance condition D. When a group member is in a disturbance condition and calls for reserves - ✔✔D. When a group member is in a disturbance condition and calls for reserves What does governor droop accomplish? A. A decrease in generator shaft speed and an increase in generator's MW output B. The demand at a given instant of time and the demand averaged over an hour C. A graphical method of representing the performance of a governor D. Enables all governors to share in frequency regulation, ensure generators do not enter into power oscillations - ✔✔D. Enables all governors to share in frequency regulation, ensure generators do not enter into power oscillations When should a system operator request another control area in the Interconnection to be placed on constant frequency control? A. When frequency is erratic B. Upon frequency decline
In an effort to allow generating units to (on AGC control) respond to frequency (in response to interconnected Hz deviation) according to (contributing system) size, what (primary) calculation is utilized? A. AGC Time Error Bias B. Frequency Bias C. Tie Line Bias D. Economic dispatch - ✔✔B. Frequency Bias How many minutes does a member of a reserve sharing group have to return ACE to zero after the initiation of a disturbance? A. 10 B. 15 C. 5 D. 1 - ✔✔B. 15 Control Area A has determined that its system security is severely endangered by remaining interconnected. Frequency is declining fast. Control area A is supplying 200 MW to the Interconnection through its one remaining tie line. Interconnection load is 100,000 MW. Control Area A load is 1000MW. Control Area A should... [select the most correct text to complete the statement] A. Open the last tie line immediately B. Remain connected (with no other action) C. Bring all generation to full load before separating D. Trip 200 MW of generation - ✔✔A. Open the last tie line immediately A single control area's disturbance is the sole cause for a frequency dip. The frequency has stabilized at 59.75 Hz. Manual load shedding is the only option to restore frequency to 60 Hz. The entire Interconnection load was 10,000 MW at the time of the Disturbance and all connected generators have a 5% droop characteristic and the control area's frequency bias is 175 MW/0.1 Hz. Approximately how much load (from the following most correct range) needs to be shed to restore frequency to 60 Hz? A. 25 - 75 MW B. 130 - 250 MW C. 275 - 360 MW
D. >400 MW - ✔✔B. 130-250 MW....6-10% load drop should restore frequency 1 Hz. That would be 600 to 1000 MW. There is only a need to raise frequency .25 Hz, therefore 150 - 250 MW. I would select b as the answer! What is the first thing a system operator should do after a relay operation? A. Call the supervisor B. Check targets and equipment C. Notify adjacent control areas D. Check power system stabilizers - ✔✔B. Check targets and equipment Which of the following is the most suitable equipment for reactive reserve response to a contingency? A. HVDC B. Series capacitors C. Shunt reactors D. Synchronous condensers - ✔✔D. Synchronous condensers If a system is supplying reactive, it would operate the generation in a condition of... [Select the most correct answer to complete the statement] A. Unity B. Synchronous C. Overexcited D. Underexcited - ✔✔C. Overexcited When evaluating a line outage request, which of the following should NOT be a major concern? A. Maintaining schedules B. Damaged equipment C. Under frequency tripping D. Unacceptable levels of reactive power - ✔✔C. Under frequency tripping NERC is looking for the least concern...
