Recent content by JGrecs

Homework Statement Draw and label the 3-phase voltage waveforms where VAN= 347∠0° Vrms, VAB= 600∠30° Vrms, Frequency: 50Hz, Volts/Division 200, Time/Division: 2 ms 2. The attempt at a solution Im really not sure how to tackle this one. My prof hardly went over this in lecture, but gave this...

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Homework Statement Three load each having a resistance of 16 ohms and an inductive reactance of 12 ohms are wye connected to a 240V three phase supply. Determine: a) the impedance per phase b) the current per phase c) the kVA total d) the Power Factor e) the kW total Homework...

Nice! Good find :smile:

Yeah my prof likes to throw us off with his wording heh. Thanks again for your help. I have 3 more questions to go. Ill post them in this thread If I am stuck.

Ok, so "per terminal" refers to "Line-to-Line"? so Id go with these: kVA= 1.732 X 230V X 40A kVA= 16kVA P= 1.732 X 230V X 40A X 0.85 P= 13.5kW Also, the 15HP (11kW) stated in the original question. Would that be the motors rated power, while the 13.5kW calculated would be its input power?

A) Wye: kVA= 1.732 X 230V X 40A kVA= 16kVA Delta: kVA= 1.732 X 230V X 69A kVA= 27kVA B) Wye: P= 1.732 X 230V X 40A X 0.85 P= 13.5kW Delta: P= 1.732 X 230V X 69A X 0.85 P= 23.4kWHow do these look?

3 PHASE INDUCTION MOTOR A 15 hp/230V, three phase induction motor has a full load current of 42A per terminal. 15HP= 11kW find: a) Full load kVA input b) If the full load power factor is lagging 0.85, what is the kW input. My question: How do I know whether its connected Wye or Delta?a) kVA=...

Thanks for the help, Gneill & Aussielec.

Ok, A) According to textbook: VLoad=VPhase=VLine (Delta) Therefore VLine in this case = 240V B) According to textbook: ILine=IPhase X 1.732 (Delta) IPhase=100A (Would you agree)? Therefore ILine= 173.2A c) kVA= kW/PF kVA= 43/0.6 kVA=...

each phase of a three phase delta connected generator supplies a full load current of 100A The Windings? 100A per phase/winding

No answers provided. You say for b), that the line current is 100A. Does this mean that the Load current=Line current for delta connections? Also for question a), If I am not mistaken, the phase voltage is calculated Vload/1.732 which comes out to 138.5V. So shouldn't VLine be 138.5V?

^ Yes. What I am unsure of is question c and d. I am not exactly sure which values to substitute into kVA= (1.732)(VL)(IL)/1000 and P= (1.732)(VL)(IL)(0.6). I used the line current and line voltage for both. Is this right? (assuming that the line current I calculated is correct to begin with.)

Homework Statement each phase of a three phase delta connected generator supplies a full load current of 100A at a voltage of 240V and at a power factor of 0.6 lagging. Find: a) line voltage b) line current c) the kVA rating d) the KW 2. The attempt at a solution a) Line voltage = Phase...