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    PE power reference 4 sale

    I passed Oct 2016 exam on 1st try after many years out of school. I don’t use a lot of reference, however I tried my best to compare and categorize each problem, I went over each book 3-4 times. During the exam I can quickly figure it out the right approach. I hope my experience will help you...
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    Graffeo Ex 7

    how does the load current IAB= source current Iab, and the current pass ZLN is equal to  √3 Iab ?
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    Motor CB size (NEC question)

    see below figure. 5-hp FLA is 7.6, 15-hp is 21, 40-hp motor is 52 based on 2008 NEC 430.62(A), then 7.6+21+52*1.25=93.6 based on 2008 NEC 430.152, the branch circuit protective device for the 40 hp motor is 250%*52=130..... I don't have 2008 NEC, what's 430.152? I can't find similar thing in...
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    NEC Table 310.15(B)(2)(a) and (b)

    If I have rated 90 degree #12 THHN runs in ambient 55 degree, the capacity is 30A based on 310.15(B)(16). Because it is used in 55 degree, the factor need to multiply. If use (a), the factor is 0.76, however if use (b), the factor is 0.84, which one shall I use?
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    difference NEC Table 310.15(B)(16) and (17)

    the table in NEC2014 is always referenced to find out the conductor capacity. I am still not sure the difference by reading the title of table.
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    Change the base

    the formula to change the base is  Znew-pu = Zold-pu *(SBASE-NEW / SBASE-OLD) * (VBASE-OLD / VBASE-NEW)2 , but based on ZB = (VB)2/SB , the formula shall be upside down like Znew-pu = Zold-pu *(SBASE-OLD / SBASE-NEW) * (VBASE-NEW / VBASE-OLD)2 Right?
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    Graffeo Ex 14

    When I use MVA method instead of PU method, the result is different. Do I miss something?  ILoad = 120∠0° / (10+j8) = 120∠0° / 12.8∠38.7° = 9.4∠-38.7° Q = I2Z = 9.4∠-38.7° * 9.4∠-38.7° * (1+j3+10+j8) = 88.4∠-77.4° * 11√2∠45° = 1375.2∠-32.4° = 1161.1-j736.9. So the active power is 1161.1 and...
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    Spin-Up, Complex Imaginary, which is better

    Try to work on more practice exam, any suggestion? Does CI NEC Drill book helps? Thank you! 
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    Can PE Power exam help changing job?

    I am thinking of working for utility company. I have no experience with power transmission, substation, relay protection...my current experience is PLC automation for long period time. This industry is not stable comparing to utility, and this industry doesn't require PE license as long as you...
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