Answer / saadi

Can i connect Dyn11yn11 parallel with Dy11y11 – DeltaHV side Dual LV winding star connected? I have 7 dry transformers with Dyn11yn11 configuration but we didn’t connect neutral with the transformer. Now i am thinking to order a new oil transformer of Dy11y11 configuration. According to my understanding, there won’t be any problem because the difference is just having neutral connection out or not?

what are the major & minor faults that occur in an inverter and in UPS ? And how to repair and resolve them ?

0 Answers  

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WhY PF low at Time of PT Missing in HT Meter

2 Answers   HCL,

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what is the maximum load sutiable from earth to phase and what is the max voltage earth to phase suitable

1 Answers  

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1)what is hypo test. 2) which cable need to hypo test.3) when hypo test can be done before or after glanding.4) what is the purpose of hypo test.

5 Answers  

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why is electricity produced and distributed in multiples of 11. 440V, 11KV, 22KV, 132KV etc

2 Answers   Bhel,

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which pump used in STP

0 Answers   Dalkia,

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out of all machines which have highest efficiency and why?

2 Answers  

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what will happen if i will done heart shape hole in transformer core?

1 Answers   Bhel, ONGC,

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Thermal withstand capability under full short circuit conditions, in terms of number of times of occurrence of short circuit and corresponding anticipated percentage reduction in transformer life.

0 Answers  

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What is dc current source? Differentiate between ideal and non ideal current sources?

0 Answers  

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While connecting the flood light plug on to the 415 V distribution panel,there was spark and the cable got burnt. Three ignitors of the flood light also burnt of. The lamps are of 400 W (total 6 lamps) connected through 1.5 mm2 cable. The plug was immediately removed from the circuit. There was a 30 mA RCD connected and a 250 A MCCB; however both did not trip. What could be the possible reasons for the circuit devices not to trip?Can someone assist please. Additional info if needed can be provided.

2 Answers  

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what do you mean by the "bay" in a switchyard? how to determine exact number of bays in a substation?

8 Answers   Essar, L&T,

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