Answer / pillay

You need a magnetic field to produce electrical energy.This
can be produced from electro magnetic means . What if during
a power failure when the DG set usage is most wanted and the
electrical source from a battery is also not available say
due to battery failure or discharged battery.To avoid such
situation a permanent magnet is used instead for initial
excitation.

Why electric traction is used ??

3 Answers   IOCL,

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Why derating factor os applied on Cables?

0 Answers  

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which type of material is used to transformer laminated core?

6 Answers  

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why cable i burning without tripping. how can protect led street lights

0 Answers   Cosma,

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Give the topology of current amplifier with current shunt feedback?

0 Answers  

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How can we calculate single phase load into three phase load

2 Answers   Jindal, Tanfac,

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what is the mechanical safety of DG ?

0 Answers  

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how hazordious area is classified at an oil & gas plant and categorise suitable class of electric equipment in that area like induction motors, LCS, Lighting Fixtures Fluerescent/Flood lights Mercury& sodium lights, J.Bs, Power Cables etc

2 Answers  

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What is negative phase sequence?

7 Answers   Hindalco, Universal Associate,

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For polarity test on a 11/3.3kV 2.5MVA delta-star Unit Auxiliary transformer,415V 3-phase supply was applied at the HV. Connection between Aa was made with a 2.5mm cable. As soon as power was switched on the cable caught fire and burnt. This test was then abandoned. It is noteworthy to say that a similar cable was also used in a similar transformer for the same. The cable did not burn and test was successfully completed with good result. What is wrong? Please, help me out.

3 Answers  

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IP55 protection stands for

1 Answers   Hofincons,

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how much maximum load a 2 core (Single phase) 16mm aluminium wire can take ?

0 Answers  

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