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    capacitive reactance

    Where are my fellow TN grads? Dr. MJR anyone?  I know there's some of y'all around here who've experienced the total hell I did.  But I respect him and am grateful for his rigor. He made me a better student, as I'm sure the rest of you would agree. @TNSparky 
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    capacitive reactance

    The "math" you speak of in EE is in the DSP and communications fields. Damn, what a nightmare.  I enjoyed Fourier and Laplace analysis.  The magic of these operations are purely genius, especially, after you're able to wrap your mind around what these operations are actually doing and how a time...
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    capacitive reactance

    I don't approach anything with a convoluted thought process, at least not in my own mind.  I work from my strengths and how a problem makes sense to me.  Most of my explanations are due to my professional experiences, development and preparation for the PE.  I understood the material in much...
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    capacitive reactance

    @rg1 you're correct.   Thanks for saving me the typing :thumbs:
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    How Many Months Should you Study to Pass? We asked our Students that Passed April 2017

    Also, a few others: -Braking -NEC related concepts (protection, wire sizing, etc.) -Limiting starting current -Interpreting nameplate data  These are more general but deserve at least a cursory review.
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    How Many Months Should you Study to Pass? We asked our Students that Passed April 2017

    For obvious reasons, I will not give you exam questions, however, I will say this: Learn how synchronous machines operate.  What does it mean for a machine to be synchronous?  What regulates the speed?  How do you adjust terminal voltage if speed, torque and other parameters are fixed?  How do...
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    How Many Months Should you Study to Pass? We asked our Students that Passed April 2017

    If you're weak in motors, learn the basic operation of each type and then dive into the concepts.  I have preached this before, but I can't stress it enough.  You will be hit harder than a "Tyson in his hayday" uppercut with concepts.  I can almost guarantee with 100% certainty that you will see...
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    3-Phase Transformer Backfeed

    The primary differences between these loads and resistive loads - they are passive energy storage devices (magnetic field for inductive and electric field for capacitive). Resistors store no energy, they dissipate.  And it follows from this that you get into the mathematics, PF correction...
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    3-Phase Transformer Backfeed

    Agree, and yes, the fuses are two-fold - they protect and isolate in the event of an internal failure/case fault/etc., but they also protect the system from the caps themselves.  I was simply illustrating that the behavior of capacitors (and inductive loads) are very different than resistive loads.
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    3-Phase Transformer Backfeed

    I was thinking in terms of the fuses protecting the system from the caps, not the other way around.  Maybe that's what you were saying and I misunderstood.  Sure, a very simple concept, but often times misconceptualized.  Most think of a fuse bank as protecting down line sections (i.e. caps...
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    3-Phase Transformer Backfeed

    From a mathematical, numerical standpoint, that is correct.  However, I was purposely dodging the math for a number of reasons, including core design, flux, reluctance, leakage reactance, hysteresis, load and other factors that would dictate the actual voltage present on the "open" phase.  I was...
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    Short Transmission Line Problem

    Also, under normal operation for each respective machine, what are the differences between an induction and synchronous machine?  Why are there any differences?  Why would we use one machine for this application, but use that machine for another one? I'm posing these scenarios to expand your...
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    Short Transmission Line Problem

    I wasn't implying that you should study concepts only.  If I came off as such, my apologies.  I'm merely throwing ideas out at what topics are heavy on concepts.  We all know circuits, but do we understand what affects voltage, current and power delivered with complex systems?   For instance...
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    3-Phase Transformer Backfeed

    @cos90 you're correct, it can be seen, though at very low voltage levels (at least with regards to nominal).  If you think of a three phase XFMR, the flux is coupled between the legs of the core simply due to the design (usually either 4 or 5 legged to mitigate heating, as @PwrEngr alluded to)...
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    3-Phase Transformer Backfeed

    10-4.  That explains my struggles.
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    Vpp vs Vpn

    This exam will, with 99.99% certainty, give you line values with a 3 phase problem.  If you're not told otherwise, assume line values.  Now, you could be given a 3 phase problem, and for simplicity and to answer what's being asked, you may have to convert the circuit and any associated voltages...
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    3-Phase Transformer Backfeed

    No, not broken neutral.  Let me try to further explain so that it is more clear. Imagine a main feeder (3-phase), and at some arbitrary junction, a 3-phase tap is pulled off the main feeder.  At this junction, the lateral tap is protected by a bank of fuses (3).  Think of this tap in the same...
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    3-Phase Transformer Backfeed

    I'm only posing this for consideration by others.  Suppose you have a 3-phase tap that is protected by fuses and you lose a phase due to a line-to-ground fault.  A 3-phase XFMR is down line from the blown fuse, but is still energized on the other two phases.  On this tap, the blown-fused phase...
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    Short Transmission Line Problem

    Now that you've solved and understand this problem, drill down into concepts surrounding these types of problems.  This test is heavily weighted on concepts rather than finding an equation to plug and chug. It is a certainty that you will see problems that will require no mathematical solutions...
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    Short Transmission Line Problem

    No, you shouldn't see a question like this on the PE, not framed this way, anyway.  It definitely takes too much time for the scope of this test.  As rg1 alluded to, it is a concept that you most certainly will see in some aspect.  That said, best way to get an idea of what topics will be on the...
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