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True or False? a. Zero-sequence currents do not exist in the delta windings of a three-phase transformer when the other windings are connected in wye. I believe the correct answer to this is another question or it depends. Are the wye windings grounded, either solidly or through an impedance...

For Kaplan power sample #3, the total reactive power is given in the solutions as sqrt(3)x[P(WB) - P(WA)]. After researching many different sources, including some old circuits II lab material, and the excellent handout recommended by Flyer, I'm still not sure why the wattmeter B power is...

I realize that each of these problems is extremely fundamental (as are all of the sample problems when one recognizes which one or two basic concepts is in play) and I apologize for not recognizing the difference here. NCEES sample problem #132 is identical to EESE (Camera) power #69. NCEES #513...

Question: A single-phase transformer rated 50kVA, 2,300/120V is connected as an autotransformer as shown in the figure to boost the voltage of a 2,300V bus. What is the kVA rating of the autotransformer? Any suggestions?

Typically fire pump circuits are supplied by a tap made ahead of the main disconnecting means in the service equipment [per Article 230-82(5) of the 2008 NEC]. Per NEC Article 695-3(a)(1) the tap is not permitted in the same cabinet, enclosure, or vertical switchboard section as the service...

Scenario: 480V genset equipped with internal protective relay (27/59, 32, 50/51, 81O/U). Generator breaker set to coordinate with downstream feeder breakers and not to operate on a fault along the generator decrement curve. A time current curve based on manufacturer’s operating characteristics...