Potential Transformer

What is the purpose of the burden resistor in a potential transformer circuit?

• To limit the current in the PT
• To adjust the voltage output of the PT
• To protect the PT from short circuits
• To provide a ground reference for PT

A potential transformer has a ratio of 20:1 and a primary voltage of 11 kV. What is the secondary voltage?

• 220 V
• 110 V
• 550 V
• 2,200 V

Which of the following statements is true regarding the connection of potential transformers in a power system?

• PTs should always be connected in parallel
• PTs should always be connected in series
• PTs can be connected in either parallel or series
• PTs should never be used in a power system

What is the typical accuracy class of a potential transformer used in metering applications?

• 0.1
• 0.5
• 1
• 5

In a potential transformer, what is the voltage across the secondary terminals when the primary is open-circuited?

• Zero voltage
• Rated voltage
• Indeterminate
• Depends on the transformer rating

Which of the following parameters can affect the performance of a potential transformer?

• Load impedance
• Primary voltage waveform
• Temperature
• All of the above

What is the purpose of the insulation used in potential transformers?

• To prevent arcing between windings
• To prevent current leakage from the windings to ground
• To reduce the size of the transformer
• To increase the output voltage

Which of the following is an advantage of using potential transformers in power systems?

• Low cost
• High accuracy
• Low voltage drop
• All of the above

What is the typical voltage rating of a potential transformer used in power systems?

• 11 kV
• 33 kV
• 132 kV
• 400 kV