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I used the last two weeks to tidy up any loose ends on topics I was weaker on.  I didn't use a cheat sheet, rather I learned my materials while studying (developed comfortability) and let that be my "cheat sheet."   There's not a template that is all-inclusive such that any person could follow...

Hard to have a defined system if everyone knew the problems, therefore, either diminishing the value of being a PE or being impossible to pass.  Best I can give you is this, the test is almost identical in difficulty and style to the published practice exam. 

I have worked a lot of them at some point in my past, but I was speaking to presentation and overall layout of the book.  I takes a fundamental, foundational approach.

I, too, am 32.  Took the exam at 31, though.  I don't necessarily agree with rg1 with regards to Chapman.  I think you can almost pass the test exclusively with his book, Graffeo, NEC and NESC.  Now, I wouldn't show up with only those materials, but it is easily passable with them alone.  I do...

If you're talking about Stephen Chapman, then yes, it is an essential.  I used it almost exclusively when I took the PE (also used Graffeo, NEC and NESC, where practical).  I also used a few other college texts for specific problems, but used Chapman and Graffeo for at least 75-80% of the exam.

No, it's correct.  You're dealing with voltages here, not currents.  Now, had it been worded in terms of asking for proving the currents, then it would be lagging. Draw it out and it'll make sense.    Use this to get started: VAB=VA-VB  Plug and chug along and make substitutions and...

Dodge the problem entirely by doing what I mentioned in other posts.  No need to complicate it and make it more expensive at the same time.    I have yet to see a scenario where this configuration would be needed, at least with regards to HV, MV and distribution utility applications.

That's my point, it is almost impractical to use this winding configuration on the utility scale when other more practical, existential options are available.  Most transmission step-downs (e.g. 161-69kV or similar) are wye-wye grounded with a delta tertiary.  The tertiary serves two purposes...

So, this sounds like a zigzag has been installed near the delta so that a ground reference can be made for the secondary side.  In this case, yes, I can see where you would have to protect in a seemingly unconventional manner to offset the introduction of zero sequence from the zigzag. That...

Per the original drawing, no zero sequence current flows to the relay coils.  Zero sequence circulates in delta CTs and no zero sequence present on wye CTs due to the absence of a neutral.  X2 bushings are bonded together and floating.  Am I missing something you're trying to say? The primary...

No problem. The confusion with most of these scenarios is attributed directly to language.  However, if you think of it intuitively, it makes perfect sense.  As I've said before, the PE exam will ask you EXACTLY what they're looking for.  There should be no confusion if you're well-versed (and...

The voltage ratio may be given in line quantities, but the turns ratio of the XFMR is always with regards to phase (e.g. phase for delta is LL and phase for wye is LN).

That's a good question.  If you did lose feed from the G&T, or whoever your up line supplier is, it's customary that they be in contact with their downline utilities to coordinate events such as this and for safety measures (i.e. all clear).  With today's technology, you should also be able...

@cos90   Yes, you're correct in saying the level of this conversation is safely out of range for what the PE will test for.   Second energization?  Hopefully you don't lose your XFMR often.  I'm speaking to initial energization.  That said, should you lose a XFMR, and you have no indication of...

Also, differential schemes are EXTREMELY fast!!!!  Much faster than a generic over-current scheme.  But it should be.  We're talking about protecting a piece of equipment that could be valued in a range from ~$500K to several million.  Differential schemes are akin to a hot line tag for...

It is usually in the form of a toggle switch on the panel in the relay cabinet. You're essentially removing the differential scheme by breaking the differential protection circuit.  As for your other post, I don't readily have any documentation that says you should design your scheme with...

A differential scheme is looking for 0 amps (minus whatever tolerance levels may be in place).  Essentially, the burden is comparing input and output current based on the turns ratio (i.e. it should register ~0 amps, if not, it is recognizing an internal fault and opens up).  I may be...

To elaborate and expand further on e). above, most all relays should have a differential bypass to address your concerns with inrush current.  Generally speaking, when a XFMR is being placed online, it endures an extensive array of tests to validate it's integrity for safe operation (at least it...

To compensate for the 30 degree phase shift, the CTs on either side should be connected in the opposite configuration of that side of the XFMR.  For example, a D-Y XFMR would be CT'd in Y-D for a differential protection scheme.  However, relays exist today that can compensate and do the work for...

The "anomaly" with the math is simply that the problem statement explicitly says the XFMR is loaded at 25%.  It doesn't say the output is loaded at any percent.  Loaded, to me, means input.  I get it.  I know the math, and I understand it clearly and can see why it's done that way, but the...