Answer Posted / vishnu.t.v

A Dc generator works on the principles of faradays law of electro magnetic induction.

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1902

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What is zero of the system?

1092

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Dear all, I just want to ask an expert on this forum for some insights. For the magnetic balance test, when applied voltage on a Delta-Star transformer e.g. Dyn11, the following relationships apply for HV side: 1.  H1-H2 = H2-H3 H3-H1 2.  H2-H3 = H3-H1 H1-H2 3.  H3-H1 = H1-H2 H2-H3 For the LV side also: 4.  X1-X0 = X2-X0 X3-X0 5.  X2-X0 = X3-X0 X1-X0 6.  X3-X0 = X1-X0 X2-X0 Is there a similar pattern for Y-d, Y-Y, D-d? And how about Y-z, D-z, Z-y transformers? I've tested a YNzn5 transformer and for LV side I don't see the pattern. In this particular case I got for LV side the following (see values below): H1-H0  H2-H0  H3-H0    X0-X1  X0-X2  X0-X3 128.0  119.9  7.2      29.2   13.3   15.8 70.7   128.4  59.2     23.4   22.0   3.6 7.2    120.1  128.1    13.4   29.3   15.8 What is the relationship here for LV? For row 1 I see the relationship, for row 3 I also see but it's shifted, but for row 2 I don't see such relationship. Any suggestions, answers, someone?

1855

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What aturn on methods of scr?

1178

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WE know that for Inductor X=2pifL,In DC f=0,then X=0 so,V=IX=0;But In the DC excitation of rotor of AC generator,DC motor field coil which coils are inductor so why does not applying DC voltage short the rotor coil of AC generator and field coil of motor?If it would then DC source might be damaged but it is not happened. Why does the strand conductor of Electrical power transmission line make twist?

4382

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what is the difference b/w absolute encoder and incremental encoder?

2071

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What is critical disruptive voltage?

1312

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What is the reason of polyphase induction motor tripping suddenly on high current during running at 70% laod? Motor IR , winding resistance & inductance balance. Motor no load current is balance and ok as per mgfr. data.

2409

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if flux and load static in dc motor and supply voltage increases 20% then what happened in speed

1900

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before transformer oil dielectric strenght tests are taken the oil should be allowed to settle to remove option 1 air bubbles 2 gasses 3 contamination 4 water

1656

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We have studied about many techniques for finding the stability of system, ROOT LOCUS, ROUTH, BODE PLOT, POLER PLOT etc. In these which is used where. what are the difference among them... PLZ tell me.......

2171

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Could the power factor on electrical system can affect the registration of the kwhr meter or the CT/PT? 

1958

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Draw a circuit diagram in which if button is open we can use socket and bulb as a series test circit and if button is close than simple we can use socket as any load purpose.

1866

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Hi Suppose we have a wye/wye transformer which is grounded at both sides,in this situation, do we have ay ground transformer? in other words, ground transformer can do any thing more (while we have nuetral wire in both sides)? As the last question, what about 3rd harmonic? we have two choices: first using wye/delta transformer + ground transformer and second using wye/wye earthed connection.in the former choice, we dont have 3rd harmoonic at the secondary side but what about Yn/yn conection? do we suffer from 3rd harmonic in the Yn/yn connection?

1965

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How to calculate the multiplying factor for energy meter with ct ratio given

2018

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