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Looks like some states are releasing results....congrats to all that passed...for those that didnt posting your score here can help everyone somewhat understand how far they were off perhaps...so post your score here and exam taken so we can compare!

I personally thought I was doing ok until the afternoon, it was brutal! Goodluck to all!

IT has 2 diagrams, asks which sequence they are +, or -..one looks + and the other looks - to me, whats wrong here? answer says +

Is there anywhere I can get a cheap copy of the NESC?

It asks for smallest copper conductor size allowed on a surge protector device, refers me to article 280.23..then gives the answe as 6 awg, I dont think this is correct, in article 230.26 it says line and grounding conductors shouldnt be any smaller than 14 awg...are they wrong in the book with...

The problem asks whats being measured during an insulation test? It in the back says resistance but gives answer B, current flowing through a dielectric...option a is resistance...which is what I would have chosed, which is correct?

It asks how many thyristors are required for a 3-phase full wave rectifier...the answer is 6...but i thought full wave rectifers were made of diodes? Does it also take 6 diodes to make a 3 phase rectifier? How many thyristors needed for a 1 phase rectifier? 2?

Does anyone know whats considered high, medium or low voltage in NEC?

OK, I know if there is delta-delta, there is no phase shift from V_ll from primary side to secondary side, generally. But where does dot convention come in? for example if primary side of a delta-delta has dot at top on primary side and dot at bottom of secondary side, does this knock the fact...

Does anyone have a diagram for + and - sequence voltages/curents for a wye connected load that will show V_ln, V_ll, I_line and I_phase? I know for example I_line = I_phase for a wye load...but do the angles change? for example, if I_line = 30@45 degree does I_phase = 30@45 also? Thanks

Hey..Im trying to see different ways to approach this question. I see Vll_p*Il_primary = Vll_s*Il_secondary....on either side of the Xfmr...but shouldnt the line current on the generator side also be able to be calculated from S=VI* ? Meaning shouldnt it be also : I = S/V = 50 MVA/13.2 KV ? I...

I can now do Spinup, CI and NCEES exams pretty quickly....about 4 hrs on NCEES and a little less on CI's, probably 2 hours on spin-up...is this adequate enough? any other suggestions?

Does anyone have this book..I am trying to see why the low-voltage side current lags by 30 degrees? the problem doesnt say the system is + or - sequence...dont you have to know this in this case?

Gentleman/Ladies: I am trying to figure out the phase shift of voltages and currents in transformers...specifically in delta-wye or wye-delta. Attached is a file were I showed and tried to keep simple the line currents and voltages on both sides of a transformer. My question is...what will be...

if I have a phasor value of voltage = 120@ 120 degrees and say current = 10@-45 degrees lagging...how can I convert these to rms values....is it just add -30 or 150 degrees to each angle?

I have a problem statement: A system has S_base = 100 MVA, calculate the base current for V_Base = kV 230. They calculate it: I_Base = (100 MVA* 1000) / ( sqrt (3) * 230 kV) = 251 amps...... The statement doesnt say its 3 phase...so I went I_Base = (1000 * 100 MVA) / 230 Kv = 434 amps so...

If im given a delta 240/120 volt 3-phase load, and I want to model it as one phase.....line to neutral as if there is a neutral, like we can also do with WYE.....would I divide by sqrt(3) to get the line to neutral voltage value to use or would I use 120 volts.....when calculating parameters of...

Im getting confused on some of the 3 phase power equations. For example.... s(3Phase) = V_ll x I_l x sqrt(3) Also, s(3phase) = 3 x V_phase x I_phase....= 3 x V_ll x I_ll....what or when do you know when to use these different equations? Is the 2nd equation for calculating S across each phase...

FOR 3PHASE: P = v X I X PF X SQRT(3) FOR 1PHASE P = V X I X PF 1) ARE THESE EQUATIONS CALCULATING POWER ABSORBED BY LOAD OR POWER SUPPLIED BY SOURCE? 2) Also, in the following equations: P_phase = E_phase x I_phase x cos(theta).....the book says its the power dissipated in each phase of...

I asked a question similar to this earlier..but it was w/o a pf....I have a 19KVA load supplie by a 208/120, 4-wire, 3-phase, wye connected system....with a 0.85 pf....what is the current delivered to the load? I know w/o a power factor....I = 19kva/(208*(sqrt(3)))= 52.7 amps..but how is it...