Answer / rakesh jha

A 3-phase transfomer required it's neutral to be grounded.
In delta-delta connection, neutral is not grounded. we use
small star-delta transformer to connect with delta-delta
transfomer and neutral will be grounded.

Answer / zizo

In cases where the neutral point of three phase system is
not accessible like the system connected to the delta
connected side of a electrical power transformer, an
artificial neutral point may be created with help of a
zigzag connected earthing transformer.

why can the rotor of 3 phase slip ring induction motor not be a 2 phase rotor?

0 Answers  

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what are the types of basic earthing?and why we are doing that?

3 Answers   Bharti,

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how to calculate no. of earthing pits and their diamensions? no. of lightning arrester rods which are required to protect a building of 35 mtr and we calculate?

5 Answers   Dharampal Premchand Limited, FlowMore, Hindustan Zinc, Ispat, Maheshwary Ispat, NDDB, Siemens,

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when the supply of MSEB is cut off & all the load of the industry is driven on generator at that time the capacitor which is connected in industry for power factor control is switched off why?

1 Answers  

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In order that work may be done:(a) Two wires are necessary(b) The circuit must have a switch(c) Coal must be burnt(d) A supply of energy is required

1 Answers  

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What are the Steps for Testing of 20MVA (make:-CGL) Transformer? How many Test we have to do?

2 Answers   BSL,

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For these 2 devices what their power ratings are ? 1) single phase : AC 220V & starting amps 3Amps (i.e. starting torque) and the stabilized amps 2A ... For deep freezer 2) single phase : AC 220V & starting amps 2.7Amps (i.e. including the starting torque of a CRT monitor) and the stabilized amps 1 Amps thanks

1 Answers  

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On the secondary side of a distribution transformer, we use 1c x 630 sq mm cable. Why dont we use 4 core cables instead of 1 core cables on the secondary. Why we use aluminium cable glands on the outgoing instead of brass cable glands?

2 Answers   Siemens,

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what you have to see after one week or month from the day of installation of transformer ?

0 Answers  

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difference between substation & grid substation?

2 Answers   GMR,

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how many types are their in switchyard or substation(like D,I TYPE), what is differant between them

0 Answers  

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what is meant by transformer differential protection ?

3 Answers   BFL,

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