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I agree with you and think that your calculation are correct. I'm not sure that you're understanding the problem correctly though. It would probably help to see the problem and not just the solution. I believe that we are trying to make I1relay=I2relay so that there is no mismatch. If there is...

I agree that it is drawn in a weird way but the answer is correct. You'll need to divide the secondary side by sq root of 3 to make the currents equal. You can do this by changing CT ratios or the relay taps. FYI newer microprocessor relays can handle this task for you without making any...

Those Cram Exams might be harder than the actual exam so don't beat yourself up too bad. They are really good practice though. Try the two engineering pro guide exams and the electrical PE review exam also. Sounds like you're pretty close to passing. If you go back over the exams again I bet...

Thanks!

Can the digital reference materials be searched separately or is it just one big document. For example if you search for voltage will it search the handbook, the NEC, and the NESC all at once and give you thousands of results or can you use the search function on the handbook and the codebooks...

Yes, since the slope is steeper. Normally you are trying to match the curves with an equipment damage curve and there may also be curves from other relays that you have to coordinate with all in one graph. The settings that you can control on the relay will be the pickup, curve and time dial...

The slope of the curves are the same. The time dial settings will move the curves up and down on the graph and are different. You can make the curves operate at the same time for a given current level by adjusting the time dial. The Definite time is incorrect on Zach's graph. Definite time...

Torque ∝ V^2 * Slip/ R Since we are not changing what the motor is driving the required Torque and Resistance will be constant. I ∝ V * Slip / R When the voltage is decreased the slip will change and can be calculated with this ratio Vold^2 * oldSlip = Vnew^2 * newSlip newSlip = oldSlip...

I apologize. I had you confused with someone else on here who had just started studying. The HP conversion does work on 3 phase or single phase. I was just talking about using the 33,000 HP to (ft-lbf/min) conversion for the torque equation. Ws is in RPM so you have to cancel out the min...

The voltage drop equation is for the voltage drop across conductors. You're not being asked for the voltage drop across a wye or delta connected load that's attached to the end of the conductors. You're just looking for the voltage drop across the conductors themselves so they won't be...

That's correct. You have to pick one base for the whole system so if you can pick one where all the values are 1 the math will be a lot easier. Yes 40MVA is the actual and divided by 1 becomes 40 pu. The values with units like MVA, KVA, KW, V, A will always be the actual value and the base is...

Yea, you have to represent the sine wave as a function of time so you'll have to convert to the Peak (Max) value for most of the power supplies and converter questions. For most problems you'll need to find the Average voltage Vo. For power you have to convert the average value to the RMS...

Thank you, that is very helpful. I hate to spend too much time on this but I'm also curious. That curiosity is what gets me in trouble sometimes and causes hours and hours to waste away.

Thank you for the help. Thanks, that's a good point and I agree. I'll email NCEES with this and see what happens. The formulas they have provided certainly don't agree with each other. I noticed that they have already changed the equation once in the handbook revisions from Flux=I*W*L/CU to...

Instead of trying to estimate how long it will take to study, just start studying. When you're able to easily answer the practice test questions from the various practice exams available then schedule the test. Get the engineering pro guides technical study guide for $45 or Zach Stones...

You find your Max AC Voltage which is equal to the DC voltage for 3 ph full wave rectifiers. Because of the battery polarity it's seen as a -60 volts. Then you use I=V/R. You know you're looking for the resistor at 10 amps you have to add the batteries 25 ohm resistance. The equation becomes...

Voltage is the same as the base so it is 1. The MVA of the system =40MVA/The base MVA = 1 so 40/1 = 40pu. Z=V^2/S so 1^2/40=.025 pu

Buy the NCEES practice exam, take it and see how you do on it. That will give you a good idea of how much you need to study to pass the test.

Dang, sorry about that. I was totally thinking about transformers instead of generators.

Page 25 in the NCEES Handbook It seems like the Flux equation flux = II*W*L without being divided by the Coefficient of utilization would be correct. Is this correct and the handbook is wrong? The three equations just don't seem to agree with each other if you divide the flux equation by CU...