why to need a electrical earthing?

2 Answers  

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How we can calc. the Backup time of a battery Bank???

6 Answers   Emerson,

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Why use only DC supply to charge batteries why not AC Supply??

3 Answers   APC, Emerson,

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what is formula in determining the size of Circuit Breaker for transformer with the following specifications. 7 units of 1600 volts (primary) and 400 volts (secondary). Both Primary and Secondary will have a circuit breaker which is SF6. What should be the Switchgear Main Breaker Size anf the sizes of each brances Circuit Breaker for Primary.

1 Answers   ABB,

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sir please send me techinical questions for junior engineer posting in bangalore railway i am diploma holder

0 Answers   RRB,

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Is it possible to download the Siemens Selection Chart(TYPE 2 coordination) for 1) fuseless selection 2)Fuse selection

0 Answers  

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in 31.5 mva power transformer how to set of wti and oti?

1 Answers   HMEL,

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What will happen when a DC series motor suppllied by an AC source ?

2 Answers  

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wat s the difference between diode and capacitor

20 Answers   TCS,

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How Can we calculate the rating of a cable?Show the formula?

2 Answers   Jindal,

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what is lrs tank water resistance.

0 Answers  

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how rated the neutral voltage of transformer and reactor, e.g. 400/220, 200MVA transformer have neutral voltage of 33kv. and reactor voltage 145kv. how this rating decided?

1 Answers   MEIL,

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