NERC Study Set Latest Update 2024-2025 250
Questions and 100% Verified Correct Answers
Actual Exam Guaranteed A+
______ is the device with moving blades that extracts energy from a flowing substance (
air , water , or steam ) pushing against its blades and converts it to electrical energy by
turning a generator .
A 500 MW generator in your Balancing Area has a droop setting of 5 % . It is currently
operating at 300 MWs . If frequency of the Interconnection dropped to 59.94 , what is
the resulting MW output of the generator?
•400 MWs
•325 MWs
•290 MWs
,•310 MWs - CORRECT ANSWER: •310 MWs
A 500 MW generator trips in a Balancing Authority outside your Balancing Authority Area
. Which of the following responses would you expect to see in your area?
•Frequency above 60 Hz
•Net Actual Interchange greater than Scheduled Interchange
•Reduced Net Actual Interchange
•Reduced net generation on your system - CORRECT ANSWER: •Net Actual
Interchange greater than Scheduled Interchange
A 700 MW generator in a Balancing Authority area trips due to operator error . Which
control system on the remaining generators would respond to the drop in system
frequency resulting from the loss of generation?
•Automatic voltage regulators
•Special protection systems
•Differential relay systems
•Governor control systems - CORRECT ANSWER: •Governor control systems
A Balancing Authority experiences a Reportable Balancing Contingency Event which
results in ACE dropping to -540 MW . The BA's ACE was 0 prior to the event . Ten
minutes into the recovery , a 150 MW generator trips , resulting in ACE dropping again .
What must the BA return its ACE to by the end of the recovery period to be compliant ?
A Balancing Authority has a normal load of around 8500 MW . Its most severe single
contingency is a 700 MW coal - fired steam unit . At 0810 , the ACE value was at -55
MW when a 600 MW generator in the Balancing Authority's northern area tripped off line
due to a generator differential . This event resulted in a large negative ACE for the
Balancing Authority . What value must ACE return to and in what time frame to avoid a
DCS violation?
• Zero ACE in 15 minutes
• 55 MW ACE in 10 minutes
• Zero ACE in 10 minutes
• -55 MW ACE in 15 minutes - CORRECT ANSWER: • -55 MW ACE in 15 minutes
A Balancing Authority has a tie - line meter that has been verified reading 5 MWs high .
The flow on the tie line is out of the BA's Area . What effect will this have on the ACE
reading?
•ACE will not be affected by the inaccurate reading
•lt depends on whether frequency is high or low
•ACE will read 5 MW above its actual value
•ACE will read 5 MW below its actual value - CORRECT ANSWER: •ACE will read 5
MW above its actual value
A Balancing Authority has an ACE of -50 MW when Interconnection frequency is 60.04
Hz .Is the BA in danger of exceeding the Balancing Authority ACE Limit (BAAL)
, •Yes if the BA's Frequency Bias is less than or equal to -100MW / .1 Hz
•Yes , if the BA's Frequency Bias is greater than -100MW / .1 Hz
•No , there is no low BAAL when frequency is high - CORRECT ANSWER: •No , there is
no low BAAL when frequency is high
A Balancing Authority has discovered one tie line meter reading is off by 30 MW ,
causing the ACE values to be incorrect What should be done to temporarily adjust for
the error until the meter can be calibrated or repaired ?
•Take the numbers from the incorrect tie line and insert them into the Nls portion of the
ACE equation
•Change the Frequency Bias part of the ACE equation to reflect the error
•Use the IME portion of the equation to adjust for the meter error
•Change the AGC mode to Flat Frequency Control - CORRECT ANSWER: •Use the
IME portion of the equation to adjust for the meter error
A Balancing Authority has lost the ability to calculate Reporting ACE starting at 13:15 .
At 13:45 , capability has not been restored . The Balancing Authority must notify the
Reliability Coordinator before what time?
A Balancing Authority has one of its tie - line meters out of service for maintenance .
Which of the following actions would be appropriate for operating the area on Automatic
Generation Control?
•Use the Meter Error part of the ACE equation and remain in Tie - Line Bias mode
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Tutordiligent. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $20.49. You're not tied to anything after your purchase.
