I'm new on here so hope this is a correct place to post this question. I'm working through ppi2pass' Power Sample Exams for Electrical and Computer PE Exams (3rd printing). I encountered the following issue with a problem and, of course, ppi2pass has no errata on it.
On page 4, problem 12 is stated "A 60Hz., three-phase, 208V system uses a capacitor to correct the power factor. The capacitor is rated at 440V and 150kVAR. What is most nearly the reactive power provided by the capacitor?" The bank is rated for 440V. So this is a de-rating problem. The issue however, is that the author utilizes 208V for the de-rating, as if the cap bank were connected line-to-line. No one in their right mind would do this. Cap banks are always connected line-to-ground to minimize voltage, insulation requirements, etc. So the cap bank should see 120V which de-rates it to about 11 kVAR.
My concern is that this sort of issue will appear on the test of course. From a construction standpoint, one must make the connection that the cap bank is connected line-to-ground and utilize 120V. Am I crazy for thinking this and what do you think I see on the test?
On page 4, problem 12 is stated "A 60Hz., three-phase, 208V system uses a capacitor to correct the power factor. The capacitor is rated at 440V and 150kVAR. What is most nearly the reactive power provided by the capacitor?" The bank is rated for 440V. So this is a de-rating problem. The issue however, is that the author utilizes 208V for the de-rating, as if the cap bank were connected line-to-line. No one in their right mind would do this. Cap banks are always connected line-to-ground to minimize voltage, insulation requirements, etc. So the cap bank should see 120V which de-rates it to about 11 kVAR.
My concern is that this sort of issue will appear on the test of course. From a construction standpoint, one must make the connection that the cap bank is connected line-to-ground and utilize 120V. Am I crazy for thinking this and what do you think I see on the test?
