What are the usege & different between UPS & batteries with charging system in in Substation?( UPS 120V AC & battery charger is 120v DC)

1 Answers  

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can u tell the difference between star - star transformer and delta to delta transformer?

2 Answers  

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why we are using auto transformer in sub station mostly???

2 Answers  

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how will protect transformer agint overcurrent protection

6 Answers   MPSEB,

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When are the directional relays used?

0 Answers  

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Office , overtime and television how big this stage?

0 Answers   ONGC,

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How can get C license i am complete I.T.I electrician trade and 10 years experiance this field and i complete the dee from ksou by distance mode of this year.ksou means karnataka south open university but i want Tnelb license

2 Answers   C License,

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What happens if the negative to earth voltage is greater than positive to earth voltage in the battery of substation?

0 Answers  

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Can anybody explain me the electrical circuit of indian railways to drive electrical engines(LOCOMOTIVES)? How does overhead lines work in the circuit to drive different trains on the same track?

1 Answers  

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If the supply voltage is same (say 440V) whether a system designed for 60 Hz frequency will work with 50 Hz frequency or not , if so pl. give clarification.

11 Answers   ABB,

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why we need of power factor correction? give advantages

3 Answers  

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what is the purpose of bypass mode in energy lighting transformer?

0 Answers  

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