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@Stephen2awesome @rg1 i thought so. Thank you for your replies.

I've seen 2 different equations  from 2 different references for finding the GMD for 4 conductors. -one used (D12 x D23 x D13 x D14 x D24 x D34)^(1/4) -the other used (D12 x D23 x D13 x D14 x D24 x D34)^(1/6) i assume one of them is wrong? which one is correct? im leaning towards the 6 root...

@rg1 OH I see now. this question really had me confused but I understand why i had so much trouble solving it now. Thank you for your help, really appreciate it!

@Stephen2awesome @rg1 thanks for your explanations. I think i understand now. I initially tried to solve for Ipri in the Sauto equation under fig. 17 then I tried to solve for Icomb by plugging in Ipri and Isec into the equation above it - it is from a reference i purchased from a website. can...

I was able to solve the problem by solving for low side current, I2, first. But I was unable to solve the problem when I try to solve the problem by finding the high side current first. I am doing: I1 = (500MVA)/(200/sqrt(3) KV) = 3765A. What current did I just solve for? when I solve for this...

Can someone please explain the solution to me? Question: A wye-wye, 230 kV, 3-ph transmission line is being stepped down to 200 kV using three autotransformers connected between the neutral and the line. For each phase, if the autotransformer is rated for 500 MVA, and the turns ratio is 5:2...

Please explain to me why sin(delta2) = (P1/P2)*sin(delta1) I don't understand how it got to that step. can someone please show the steps leading up to how sin(delta2) is determined? Thanks!

I didn't purchase if from Brightwood. I got this exam (in pdf format) from a colleague and was told it is the Kaplan exam.  My guess is it is probably an older sample exam as it has many errors. I found this thread dated 2010 in the forum where a poster called cableguy made an errata list and...

Hello, What equation is being used in the solution? (question from Kaplan sample exam) Is max torque synonymous to max power?  In Graffeo's book I see the formula: Slip at which Pmax occurs at = Sp = Rrotor/(Rrotor + Zeq), where Zeq = Zmotor + Zstator. But this equation seems slightly...

I often find myself making the mistake of using Vpp rather than Vpn and vice versa. After I see the solution and realized the mistake I made, it seems so obvious from the start that I should have used Vpn. Question 1: are there any techniques or rules to follow to be sure what voltage potential...

Thanks for the clarification. I didn't take any power courses in college and have been learning power through books and online material so I really appreciate the effort other forum members put in to answering my questions and explaining the fundamentals.

Yes, this makes sense...though I'm more used treating positive P or Q as generating/outputting power rather than as loads because I work for a utility company. But the concept is the same but reversed. My confusion was addressed when I took a look at the cheat sheet on your website...

I see. I misinterpreted the CT ratio as the transformer turn ratio but the CT ratio is the ratio (Ipri/Isec) which makes a lot more sense. Thanks for the explanations.

turn ratio = (Npri/Nsec) = (Vpri/Vsec) = (Isec/Ipri) shouldn't Ipri in the example be Ipri = (Irelay)/(CT ratio)??

Hi, I've always used this rule of thumb: lagging generator (over-excited): exporting Watt and exporting VAR leading generator (under-excited): exporting Watt and importing VAR lagging motor (under-excited): importing Watt and importing VAR leading motor (over-excited): importing Watt...

Thank you all for the detailed explanations.

Hi guys, I would like a better understand of the numbers in this problem. does this mean that the transformer in this example is overloaded (75KVA on 15KVA rate transformer)?

Thank you! This was very helpful and explained the solution very well. I wasted so much time trying to understand the author's solution but just got more confused.

Hi, Can someone answer these questions: 1) Am I correct in thinking that Vbc = 480V and Vab = 120V? 2) Why is only I2 multiplied by 600V? Thanks

yes this makes sense and is much easier to see when the circuit is drawn out as is in your reply rather than the one line diagram in the solution. thank you all for the replies.