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I think we're making the same argument, just that I was mistaken due to not fully reading the problem statement.  Since they've provided a base, I would use your approach.  Sorry for the confusion. Good debate.  Keep the problems coming.   Since passing the exam, I seem to have a knack for...

Nvm, maybe we're making the same argument.  Mea culpa.

Is phase voltage in a delta configuration not the same as taking a volt meter and placing the leads across any 2 phases?  If not, then any 3-phase academia I've ever learned has been a farce!!  I've still failed to check this due to being consumed with other things, but Vt (terminal voltage) in...

Well, if I were you and I wasn't given the proper info, I'd be questioning it; but as previously stated, you will be given all necessary info/ratings on this exam.  You will have to make assumptions, but you will know -if you're prepared, well-versed and understand what's being asked for- what...

Then if you use that assumption across the board, the generated voltage per phase in this circumstance should be divided by sqrt3.  I don't agree that this assumption is "safe."  It's not like we're working with a motor/generator/XFMR that looks entirely to be an inductive load at start-up...

No one has given credence to my points raised previously.  Right or wrong, a confirmation of the winding configuration is necessary to determine what the "phase" voltage generated actually is?  I didn't get a chance to review today, but as previously stated, the winding configuration will...

Phase voltage (Vt) for a wye connected system must be divided by sqrt3 if working from a line quantity.  I can check tomorrow in some texts and corroborate, but I'm confident this must be considered, thus, a connection should be given.  If not, I don't know that you can fully answer the question...

To eliminate confusion, the sqrt3 is not a product of the run-of-the-mill use that is seen in power calculations.  It is actually a factor of the distance, but due to phase shifts between phases in 3-phase systems, this is why it is sqrt3 and not 2.  Remember, this is under balanced conditions...

Let's plug in some numbers for a bolted 3-phase fault condition at the secondary terminals: 161 kV - 13.2 kV, 20 MVA, 7%Z 20MVA/(sqrt3*13.2) = 874.77 A @ full load on secondary  IFLA/.07 = 12496.71 A of available fault current at the secondary terminals As for your concerns about resources...

@applepieordie Just for clarity and standardized convention, S=VI* is not apparent power, rather, it is complex power (also P+jQ).  Yes, I suppose it could be defined as such, but from academic, theoretical doctrine, there is a difference in "definition."  Apparent power is defined as VI...

And every fault outside of a bolted 3-phase fault is unsymmetric, which means almost every single fault on a real power system will be of the unsymmetric type.

The confusion stems from candidates misinterpreting what is primary and secondary on a CT.   Cos90 is correct that Np=1 in most circumstances, but understand this is not how CTs are rated/defined.  Conventionally, CT ratios are along the lines of 400:5, 600:5, 800:5, and 1200:5, just to name a...

If you're looking from the point of view of the secondary of the station XFMR down line, you have to develop the zero sequence impedance for the ground grid. The ISC for the transformer you gave above concerns a bolted 3-phase fault at the secondary terminals of the XFMR, and that is the...

CTs take a relativey high current and reduce it to a readable/measureable quantity.  Conversely, if CTs are not properly shunted when not in use, it then looks like an open step-up XFMR (could be on the order of 10s - 100s of thousands of volts, depending on the system being measured).  ...

Agree.  The questions are proverbial softballs that should be knocked out of the park.  Not to say it's completely out of the realm of possibilities that they will not make you use your noggin', but you shouldn't struggle with them if you understand what they're asking for (present worth, future...

Demand/energy management and load factor are all somewhat similar; and essentially, you'll need to take into account the total available output in some timeframe, and relate it to what was actually used/consumed in that same timeframe (think of a 5-gallon bucket of water with 3-gallons in it -...

Yes, similar to FE.  From my experience, it was very straightforward.  

True, rg1.  But I find it more advantageous to be successful if one understands concepts more so than a generic memory trigger.  For those who have sat for this test can agree that understanding concepts, more times than not, will determine any given candidate's ability to pass.  Those who know...

The diagrams from Graffeo are merely graphically illustrating, in a counterclockwise and clockwise direction,  depending on the PF, what is meant by leading/lagging PF.   There are a few things to keep up with, and you can think of it or remember it in many ways, but PF is with respect to...

No confusion, but it's a fundamental concept that has to be understood to move forward with -why?- you don't account for a return path in 3-phase applications of this type.  Forget about distance, I'm not talking about distance -or counting something twice-, purely concepts.