Which system use dc to dc high voltage gain A. Solar system B. Battery backup

1 Answers  

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when will cause the negative sequence falut in electrical system?

2 Answers   Schneider,

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How one can say about a device (e.g: a light holder contains 20 or 30 L.E.Ds which glows when power supply is off, from which source they are getting the supply..... battery or capacitor) without removing and opening up its case ?

1 Answers   CMC,

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How could I get a certificate of competency as Electrical Supervisor? I have completed By BTech in Electrical this year(2012) for VJTI Mumbai Maharashtra. Is it compulsory to be produced while joining?

0 Answers   ONGC,

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what is the difference between ac and dc?which one is more efficient?and what r their advantages

1 Answers  

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Define piezo-electric effect?

0 Answers  

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why we provided electrical earthing?

5 Answers   CPCL,

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assume we are put both df/dt and vector surge relay in same bus the df/dt relay setting is +5 hz an -5HZ. we want operat the vector surge relay before the df/dt how i calculate the setting of the vector surge relay.

1 Answers  

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why use celling fan wing is two or three ?

2 Answers  

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in traction which type of supply are used

15 Answers   APGenco, Construction,

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I need a 33/690V Dry type transformer.How to select IP class for this transformer.This will be an outdoor transformer located in a highly polluted environment.

3 Answers  

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In case of generator when we consume more power produces by it why load on generator increase and starts sound more. and how it is adjusted..

0 Answers  

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