Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min)_ Attempt review.pdf

26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Dashboard / My courses / EL25 - Test and connect transformers / Topic Assessments / Topic Assessment 2 Auto-transformers and Instrument Transformers (6...

26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Dashboard / My courses / EL25 - Test and connect transformers / Topic Assessments / Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min) Started on Monday, 26 August 2024, 9:00 PM State Finished Completed on Monday, 26 August 2024, 9:03 PM Time taken 3 mins 3 secs Marks 15.00/15.00 Grade 100.00 out of 100.00 Feedback Congratulations you have achieved 100%. Good luck with your continued studies. Question 1 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 1 With respect to the double-wound transformer, what is a major disadvantage of an auto-transformer? Select one: Auto-transformers have much higher copper loss Auto-transformer efficiency is the lowest of all the transformer types Auto-transformers present a high risk to both people and equipment when stepping down a high voltage to a low  voltage Auto-transformer voltage regulation is poor Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 1/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 2 Correct Mark 4.00 out of 4.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 2 What are FOUR major advantages of an auto-transformers? Select one or more: a. They require less copper than an ordinary transformer of a similar rating b. They are useful for high voltage changes c. They are safer than most other transformers d. They require a smaller magnetising current than a 2-winding transformer of the same rating e. They have better voltage regulation and operates at a higher efficiency than a 2-winding transformer of the  same rating f. They have a larger short circuit current g. They work on both AC and DC h. They have a smaller size than an ordinary transformer of the same rating Your answer is correct. Question 3 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 3 The primary of a potential/instrument transformer is connected: Select one: In parallel with the supply On top of each other In order of size In series with the supply Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 2/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 4 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 4 To ensure safe removal of a current transformer you must: Select one: Affix a danger tag Tell your supervisor Short the primary winding Short the secondary winding Your answer is correct. Question 5 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 5 The diagram below shows a typical connection diagram for instrument transformers used to monitor the supply voltage and current of a high voltage installation. Determine the actual values of voltage and current that would be applied to the meters if the line voltage was 10,950V and the line current was 140A. Select one: 54.8V, 3.5A 109.5V, 0.7A 109.5V, 3.5A 54.8V, 0.7A Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 3/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 6 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 6 A current transformer is a type of instrument transformer. What is a current transformer most commonly used for? Select one: Metering purposes Generators Starting motors Circuit protection Your answer is correct. Question 7 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 7 Review the statement/s carefully and indicate True or False. Statement True/False Instrument transformers are used in test laboratories True  Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 4/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 8 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 8 The core of a current transformer is typically: Select one: A stack of “C” and “I” laminations A moulded ceramic material with embedded ferrite A stack of “E” and “I” laminations A continuously wound lamination that is toroidal in shape Your answer is correct. Question 9 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 9 In installing a current transformer, what circuit TWO circuit components are connected in series with the CT primary conductor? Select one or more: Load supply cable The VT The secondary The control switch The load Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 5/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 10 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 10 What does a rating of 300:5 mean in relation to a current transformer? Select one: 5 primary amps at full load will produce 300 amps of secondary current when 5 amps flow through the primary winding 300 primary volts at full load will produce 5 volts of secondary current when 300 volts flow through the primary winding 300 primary amps at full load will produce 5 amps of secondary current when 300 amps flow through the primary  winding 5 primary volts at full load will produce 300 volts of secondary current when 5 volts flow through the primary winding Your answer is correct. Question 11 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 11 Question moved from Topic Assessment 3. A load connected to a three-phase, three-wire 11 000/415 V line-to-line potential requires measurement. It is estimated to be 3000 kVA. From the following, select a suitable current and potential transformer. CT to provide metering current of 0-5A PT to provide metering voltage of 110V Select one: Current transformer with 200:5 ratio and potential transformer with 40:1 ratio Current transformer with 200:5 ratio and potential transformer with 100:1 ratio Current transformer with 50:5 ratio and potential transformer with 50:1 ratio Current transformer with 50:5 ratio and potential transformer with 100:1 ratio Your answer is correct. https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 6/7 26/08/2024, 21:03 Topic Assessment 2 Auto-transformers and Instrument Transformers (60 min): Attempt review Question 12 Correct Mark 1.00 out of 1.00 Topic Assessment 2 Auto-transformers and Instrument Transformers Question 12 Question moved from Topic Assessment 3. A 1000kVA load is supplied from a three-phase four-wire 11 000 V line. From the following, select a suitable current and potential instrument transformer. CT to provide metering current of 0-5A PT to provide a metering voltage of 110V Select one: Current transformer with 75:5 ratio and potential transformer with 100:1 ratio Current transformer with 75:5 ratio and potential transformer with 80:1 ratio Current transformer with 100:5 ratio and potential transformer with 80:1 ratio Potential transformer with 80:1 ratio and potential transformer with 50:1 ratio Your answer is correct. ◀︎Topic Assessment 1 Transformer types and application (60 min) Jump to... Topic Assessment 3 Transformer Operation (60 min) ▶︎ https://learn.sydneytafe.edu.au/mod/quiz/review.php?attempt=1633210&cmid=1441012 7/7