Answer / kj

If the transformer neutral is not earth then there is no
direct path between these and therefore should not have a
voltage. But this is in a perfect world.

In reality the insulation in the transformer is not
perfect. It will have weak spots in it. When you connect a
meter between the earth and the neutral you are measuring
the voltage between the neutral and the weakest spot in the
insulation. You will find that if the insulation is good
there will be very little or no current flow if an ammeter
is connected between the earth and the neutral.

I have experienced this and have investigated to determine
why it is happening.

Why tripping not occur when the transmission lines (11KV & above) breaks? Doesn't we provide earthfault protection for it?

1 Answers  

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WE ARE PLACE A NEW 75 KW MOTOR FOR JPF.IT IS CONNECTED IN M.C.C. WHEN WE ARE STARTING M.C.C.INCOMER IS TRIPPED.THEN WE ARE CONNECTED IN P.C.C WITH A MM30 RELAY PROTECTION THEN WE ARE STARTED MOTOR WILL RUN SMOOTHLY.

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Briefly describe your ideal job?

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what will happen if dc is supplied in acb or mccb or other circuit breakers?

1 Answers  

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is there any difference between protection C.T and measuring C.T?if yes then what is the difference?

4 Answers   BARC, Century Rayon,

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At no load the PF of an alternator -Zero -Zero Lagging -Zero leading -None of the above

2 Answers  

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What are the protection required for Transformer, motor, Line, Generator, capacitor, that all i have to refer which standard?(Like Transformer detail IS 2026)

0 Answers  

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10Hp, 3-phase, 415v, 50Hz induction motor. The above motor is to run on Star-Delta connection, so how do i make following hardware selection 1) MCB, 2) Contactor, 3) Wire Gage (Depending on P-P current or Line Current), 4) OLR, Please tell in detail how to do the above, so as to get the ans. of it even if the Hp rating changes.

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In distribution transformers, fuse wires are very thin when compared to conductor size. How it's possible?

4 Answers  

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If a line which is drawing approximatly 2100amps what should be earthing streep size(using galwanize streep)?

2 Answers  

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how to calculate energy of 3-phase motor?

0 Answers   Suzlon,

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how the voltage between all the three phase is zero can any body explain me

5 Answers  

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