What are Contactors? How they works and what its highest rating?

0 Answers  

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one conductor length is L.and i am strech uniformly this conductor and made length is 2L.so resistance of this strech conductor is R=4R..but i want to know about area of stech conductor hows it become a/2..

0 Answers   Infosys, ME,

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i have 90kw motor.so i choose connect cable .please what is parameter checked so please give to formula

0 Answers   May Baker,

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if in 3-phase system voltage=440V,frequency=60Hz, current=400A. then if it is single phase then current=? and if it is single phasing then current=?

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what kelvin's law ?

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What happens if 25 Hz frequency is applied for 400/200,50 Hz single phase Transformer.Will Voltage increase ?

2 Answers   Bhel, Dawlance, IBM,

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What is the use of iron core in a transformer?

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How many types of protection relays are there based on the characteristic?

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how fault in an electric system is detected & hw protection of equipments is done ?

6 Answers   NTPC, RLY,

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What is excitation in case of dc motor?

0 Answers  

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why we not connect the 12 V batteries in parallel to get the more backup supply for an UPS ? wheter off line or on line UPS ?

2 Answers  

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what is the use of neutral displacement relay

1 Answers   OCL,

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