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Why is India's frequency 50Hz and not 60Hz like the US?

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1.  To generate power of that frequency it costs a lot and the size of the alternator is huge and it costs an incredible amount which we can't afford. 2. As frequency increases eddy current and hysteresis losses increases and hence power loss also increases. In US the frequency is 60 Hz and 110 V supply. In India it is about 220 V, 50 HZ supply. For a particular load say 100 KW, the current will be 0.416 A, but in US the same load will consume about 0.9 A. Here the thing is, the heat produced in the cable because of the flow of current will be large in US compared to India. Since US is a cold country they can use this level but not by India.
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How do you calculate the short circuit current of a power transformer?

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Suppose Transformer Rating is 15 MVA & voltage ratio 33/11 KV . So current rating ration 262.43/787.37. if percentage impedance=7.5% Then during the short ckt of Test its required 7.5% of voltage to follow full load current. So if supply 2.417 kV to follow the current 262.43 A . In Practically we supply 415 V i.e 0.1717% of 2.417kV. so during supply short ckt current follow is =262.43*0.1717= Approx 45A.
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Gas Concentration of DGA analysis of The transformer

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GAS       NORMAL          ABNORMAL             INTERPRETATION  H2      < 150 ppm        > 1000 ppm             Arcing corona  CH4     < 25 ppm        > 80 ppm               Sparking  C2H6    < 10 ppm        > 35 ppm               Local Overheating  C2H4    < 20 ppm        > 100 ppm              Severe Overheating  C2H2    < 15 ppm        > 70 ppm               Arcing  CO      < 500 ppm       > 1000 ppm             Severe Ove...
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Electrical Question Answer

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Hi, guys, you are can ask a question about the electrical practical field.
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