Answer / k.prakashchandra

You may not expect current in neutral of a 3phase
appliance. But there will be current in neutral of a 1
phase appliance while working.,

Answer / pillay

your understanding is wrong or if not
incomplete.
In any single phase circuit the neutral
is the return path
for the circuit. That means the current that
flows into the phase comes out through the neutral
Even in 3 PH balanced load you will see the
same individual ph current in the neutral but
you will see no current in the main neutral,
cos at the neutral bar the individual neutral
current had balanced up through the other phases.

Answer / snk

yes your thinking good and by law should not be flow when
open circuit.but air con working and neutral floe is the
return of current.you make your question in tow parts then it
will be help full.

How to improve the power factor from 0.8 to 0.98? Also tell me cost vs benefit analysis.

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A 400 V, 50 Hz, Δ connected synchronous generator has a field reactance of 0.1 Ω and armature resistance of 0.015 Ω. At full load, the machine supplies 1200 A at 0.8 pf lagging. Under full-load conditions, the friction and windage losses are 40 KW and the core losses are 30 KW. What is the machine’s overall efficiency? Ignore any field circuit losses.

0 Answers   VECL,

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1. A 380 / 220 V r.m.s. 3-phase 4-wire circuit carries loads of 8 + j8.1 ohm; 4 + j4.1 ohm; and 2 +j2.1 ohmin the three phases respectively. The length of the circuit is 100 m, and the resistivity of the phase conductors is 0.0005 Ω/m. The neutral conductor is of the same size as the phase conductors. a) Select a reference angle 0for the first phase. Then write down the three phase voltages in both polar format and complex number format. b) Make appropriate assumptions, and take temperature effects on resistance is insignificant. Calculate the currents in the three phases. (Note: Determine conductor resistance, and apply Kirchhoff’s Voltage Law) Based on the result, suggest a main switch rating for the circuit. c) Show your preferred direction of neutral current in a diagram, and then determine its value. (Note: Apply superposition principle, and Kirchhoff’s Current Law) Use its magnitude to show that in this circuit, the unbalanced load may increase the voltage drop in some of the phases. (Note: Also observe the common volt drip in neutral) State your assumptions, if there are any. d) Suddenly the neutral wire of the circuit is broken. Estimate the new currents in the first phase, i.e. Phase L1. State your assumptions, if there are any.

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what are factors to be consider to design a HT & LT motor?

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How does a battary stores charge in it? please explain in simple manner and in detail.thanks

0 Answers  

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is it possible to use a tranformer to regulate an unstable system voltage?

3 Answers  

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How we can calculate what type of supply we need for an example sometimes we take 11 KV and sometime 33KV from EB ?

4 Answers  

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george phenomenon of synchronous machine

0 Answers   JU,

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what type of euse we should use ? 1- High resistance & low temperature 2- High temperature low resistance

2 Answers  

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Wat is power factor exact meaning in terms of technical terms plz explain ?

4 Answers  

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what is reactive power?

2 Answers   Vestas,

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Why transformer rating in KVA? describe.

5 Answers  

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