Questions and Answers
The percentage impedance (Z%) of a transformer is the voltage drop expressed as a percentage of the rated primary voltage when full load current flows in the primary and secondary windings with a short connected across the secondary terminals.
True
To measure impedance, the primary winding of the transformer is short circuited and measuring instruments are connected to measure the primary voltage at full load current.
False
Identify the correct order of the following steps to measure impedance.
Calculate the impedance percentage (Z%) of a transformer with a measured impedance voltage of 82 V on a 3,000/240V transformer.
Signup and view all the answers
Study Notes
Percentage Impedance in Transformers
- Percentage impedance (Z%) of a transformer reflects the voltage drop when full load current flows and the secondary is short-circuited.
- Accurate determination involves short-circuiting the secondary winding rather than the primary.
Measurement Process
- The correct procedure to measure impedance involves:
- Short-circuiting the secondary winding.
- Adjusting applied voltage until the rated full-load current is reached.
- Noting voltmeter and ammeter readings.
- Calculating % impedance using the measured values.
Calculation Example
- Calculation for a 3,000/240V transformer:
- Measured impedance voltage is 82 V on high voltage windings.
- Correct Z% calculated as 2.73%.
Assessment Performance
- Assessment successfully completed with a score of 100%.
- Provided feedback emphasizes successful understanding and good luck for continued studies.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of percentage impedance in transformers with this targeted assessment. This quiz covers key concepts and problem-solving techniques relevant to your studies in electrical engineering. Achieve a perfect score and validate your knowledge!
