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  1. C

    3-Phase Transformer Backfeed

    You can read about real life events on the situation you are describing here: https://www.nrc.gov/reactors/operating/ops-experience/open-phase-electric-systems.html A famous example of this occurred on Jan. 30, 2012, Unit 2 at the Byron Station. A single phase left open can go undetected...
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    Live CBT Test

    I have created a live CBT test. Each test will consist of 80 questions which is sampled at random from a question bank. For the morning and afternoon session, you will get a total of 8 hours with a lunch break. Remember to set aside at least 9 hours before clicking to start the test. Most of the...
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    Cram Problem-Solve it get a discount

    Sure send me an email.
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    Cram Problem-Solve it get a discount

    Send me an email Ill give you a discount :)
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    Single line to ground fault

    They give it in the reference handbook. The problem listed above is very different though. It is asking this: "If I have a single line to ground fault occurs on the wye side of the transformer, what does it look like on the delta side"? This requires a little bit of thinking and is not simply...
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    Single line to ground fault

    You are mixing up turns ratio and PU. These fault values are well known for protection engineers. No matter what the turns ratio of the transformer is- if you have a line to ground fault on the wye side the 1pu appears as 0.577 pu on the delta secondary side. You are also missing an important...
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    Cram Problem-Solve it get a discount

    You got it.
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    NCEES RESULTS ARE OUT! POST YOUR RESULTS!

    Congrats!
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    Cram Problem-Solve it get a discount

    This is incorrect.
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    Cram Problem-Solve it get a discount

    First person to solve this in the comments section will get one or all of my books for a 30% discount. You must show how you got the answer. Solve in comment section here. A three-phase circuit with ABC rotation is show below. If both transformers are ideal and have subtractive polarity, how...
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    Transformer Saturation Question

    Yes that’s correct
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    Transformer Saturation Question

    Yes that is correct.
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    Transformer Saturation Question

    Question now states: A 50Hz generator is going to supply power to a 50Hz motor through a transformer designed for 60Hz. Which of the following statements is true?
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    Transformer Saturation Question

    You are correct. I have it backwards. Typo has been fixed.
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    Corner-Grounded Delta System Question

    That is incorrect.
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    Corner-Grounded Delta System Question

    Can you could draw a sketch of what you mean?  
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    Corner-Grounded Delta System Question

    Yes you are correct. I put 13.8 instead of 13.2. I just fixed the typo.
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    Corner-Grounded Delta System Question

    It is really just by observation you can see. Good question to ask for cram for the Pe Vol V! But now think about the line currents. Anyone can guess what they look like?
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    Corner-Grounded Delta System Question

    See below
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    Corner-Grounded Delta System Question

    In this sketch you have a grounded wye. So: Vag=Vcg=7.62kV if the wye source was un-grounded Vag=Vcg=13.2kV Was this the question being asked? I was not sure if this was a question or a statement.
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