We use ungrounded DC system (220V/110V) for control and protection system in substations etc. Suppose we have long 2 core DC cables running from our DCDB in control room to the load (length of around 2 to 3 km). Do we need to protect these long DC cables from earth leakages or not? If yes how?

5 Answers   Siemens,

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What is static frequency control used in gas turbines

1 Answers  

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how we can varying the speed of dc motor ?

6 Answers  

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OHMS LAW

9 Answers  

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how does it help for selection of a transformer.

1 Answers   Reddy Labs,

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As a electrical engineer.. what are the basic norms should follow in transformer oil testing.. 1.What is the Electrode type? 2.How long time you will give for oil testing?

0 Answers   NAL,

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what is the difference between current rating and breaking current of an MCCB? and for a known load how to calculate the current rating of a MCCB?

1 Answers   HPL,

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how meger function

0 Answers  

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State thevenintheorem?

0 Answers  

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what is the working principle/operation/theory of 3-phase rectifier power transformer used in cold rolling mills.

1 Answers   TATA,

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Explain what is electric traction?

0 Answers  

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how to enter inverter parameter? without manaual?

0 Answers   Essar,

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