Intro to Transformers Exam Questions and answers Newest

Intro to Transformers Exam Questions and
answers Newest
A __________ is an electrical device that converts AC electricity from one voltage level to another. -
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Correct Answers Transformer
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II! A common application of mutual inductance is found in a device called a __________. - Correct Answers
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II! II!Transformer



II! Which of the following is not a component of a transformer? - Correct Answers Plate
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II! In order to calculate the output voltage of a transformer, divide the input voltage by the __________. -
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II! Correct Answers Turns Ratio II! II! II! II! II! II!




II! Which of the following is a method to troubleshoot a transformer? - Correct Answers Measuring the
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II! continuity of the coils II! II! II!




II! Transformers are usually rated in units called __________. - Correct Answers Volt Amperes II! II! II! II! II! II! II! II! II! II! II! II! II! II! II! II!




II! The power relationship on a transformer states that __________. - Correct Answers Power in= Power
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II! out + loss II! II!




II! The current load of a transformer is the current drawn by the __________. - Correct Answers Primary
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II! winding itself II!




II! Which of the categories of transformers uses only one coil for the primary and secondary? - Correct
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II! Answers Autotransformer II! II! II! II!




II! Which type of transformer is commonly used to reduce line voltages of 240 VAC or 480 VAC to 120 VAC? -
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II! Correct Answers Control transformer II! II! II! II! II! II!

, II! A common application of a center tap on the secondary of a transformer is a(n) __________. - Correct
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II! Answers Distribution transformer II! II! II! II! II!




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which statement is correct regarding the Transformer - Correct Answers applied voltage on the primary
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leads current by 90 degrees
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II! 2. refer to Figure 1 what does the schematic symbol represent - Correct Answers iron core Transformer
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II! 3. which of the following statements best describes CEMF - Correct Answers opposes the applied
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II! voltage



II! 4. refer to schematic and figure to what will be the phase relationship between the primary and the
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II! secondary voltages - Correct Answers the secondary voltage will be a hundred eighty degrees out of
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II! phase



II! 5. which type of Transformer would be used to prevent noise from being fed back to the line without
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II! changing the voltage levels - Correct Answers isolation Transformer
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II! 6. what is the power of available from a 68 Kva transformer connected in open Delta configuration -
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II! Correct Answers 39.44 Kva II! II! II! II! II! II!




II! 7. the secondary winding of a 11000 volt to 220 volt transformer has 50 windings on the secondary how
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II! many turns are on the primary winding - Correct Answers 2500 turns
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II! 8. a Transformer has 728 turns on the primary winding and 56 turns on the secondary with the hundred
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II! twenty volt applied on the primary what is the output voltage of the secondary - Correct Answers 9.23
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II! 9. which statement is correct regarding current and Transformers - Correct Answers the current ratio of
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II! transformation is the opposite of the voltage ratio of transformation II! II! II! II! II! II! II! II! II!