ERCOT System Operator Certification FINAL ACTUAL Exam Questions and CORRECT
REVISED Answers GRADED TO PASS!!
What is the unit of measurement for electric current? For capacitance? For inductance?
Amps / Farad / Henry
What are the essential components of an electric circuit?
Voltage source, load, supply path, return path
For many actual electrical circuits, the earth serves as the return path for the current flow. True
or false?
True
A resistance of 5 ohms is connected to a resistance of 10 ohms in an electric circuit. What is the
total resistance if the two resistances are connected (i) in series and (ii) in parallel?
(i) 15 ohms (ii) 3.33 ohms
The output of a generating unit is 500 MW. Express this value in watts.
500,000,000 watts
What is the scheduled system frequency in ERCOT? At this frequency, what is the time in
seconds for the voltage to move from a peak value to a zero crossing?
60 HZ, .0042 seconds
There are electrical connections between ERCOT and the Eastern Interconnection. True or
False?
True, there are two DC ties connecting ERCOT with the Eastern Interconnection. There are no
closed AC ties.
In December, 2009, ERCOT's electrical market was changed from a Zonal to Nodal model. This
means that:
Transmission system congestion is now managed between thousands of small points (nodes) in
the ERCOT system, rather than between a few large zones.
At a certain bus, current lags voltage by 72. What fraction of a cycle does this 72 phase lag
correspond to?
1/5th
What is the peak value of the voltage amplitude for a 345 KV AC voltage?
345/.707= 244 KV
What is the phase difference between the two vectors in each of the following pairs?
Page 1 of 2
REVISED Answers GRADED TO PASS!!
What is the unit of measurement for electric current? For capacitance? For inductance?
Amps / Farad / Henry
What are the essential components of an electric circuit?
Voltage source, load, supply path, return path
For many actual electrical circuits, the earth serves as the return path for the current flow. True
or false?
True
A resistance of 5 ohms is connected to a resistance of 10 ohms in an electric circuit. What is the
total resistance if the two resistances are connected (i) in series and (ii) in parallel?
(i) 15 ohms (ii) 3.33 ohms
The output of a generating unit is 500 MW. Express this value in watts.
500,000,000 watts
What is the scheduled system frequency in ERCOT? At this frequency, what is the time in
seconds for the voltage to move from a peak value to a zero crossing?
60 HZ, .0042 seconds
There are electrical connections between ERCOT and the Eastern Interconnection. True or
False?
True, there are two DC ties connecting ERCOT with the Eastern Interconnection. There are no
closed AC ties.
In December, 2009, ERCOT's electrical market was changed from a Zonal to Nodal model. This
means that:
Transmission system congestion is now managed between thousands of small points (nodes) in
the ERCOT system, rather than between a few large zones.
At a certain bus, current lags voltage by 72. What fraction of a cycle does this 72 phase lag
correspond to?
1/5th
What is the peak value of the voltage amplitude for a 345 KV AC voltage?
345/.707= 244 KV
What is the phase difference between the two vectors in each of the following pairs?
Page 1 of 2
