Answer / k.prakashchandra

When the ups voltage = battery voltage,Number of batteries
required = desired back up hours x load /V x AH of each battery

For 7.5kw star delta starter how to calculate 1. Mccb rating 2. Contactor rating 3. Over load relay rating

1 Answers   L&T, MAHINDRA,

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Why celing fans will rotate slowly after some days.?

2 Answers  

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A 100 kVA , 400 v/250 kv testing transformer has 8% leakage reactance and resistance on 100 KVA base . A cable has to be tested at 500 kv using the above transformer as a resonant transformer at 50 hz . if the charging current of the cable at 500 kv is 0.4 A find the series inductance required . Assume 2% resistance for the inductor to be used and the connecting leads . Neglect dielectric loss of hte cable . what will be the input voltage to the transformer ?

0 Answers   L&T,

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why the genearation of electricity always in form of sine wave only ??? why not cosine wave ???

1 Answers  

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What is the cut-off rate?

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On what cycle does thermal power plant operate?

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What is the difference between AMF panel and DG Synchronization panel? please define the working of both the panels?

3 Answers   ABB, Power Grid,

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what are the safety measures of induction motor?

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what are the protections in 132 kv class electrical systems.....? hw u define that in elctrical terms..? . . .pls answr

2 Answers   ABB,

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How to design a Unit auxiliary transformer for a power house having a unit of 65 MW and Generating voltage of 11 KV and Secondary voltage of 433V

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what is the earthing condition between earth & neutral.

6 Answers   ABB,

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1600kva capacity Transformers how the bucholz relay,Oil temperature,winding,surge relay relays setting are to be done

0 Answers  

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