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.

what is the purpose of checking IR and Megger values in motor windings?

5 Answers  

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can we individually produce electriciyt

1 Answers  

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Why Alternator has 0.8 power factor?

2 Answers   Bhel,

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Alternators are invariably star connected why?

4 Answers  

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Difference between directional over current and non directional over current ?

2 Answers  

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OUR METER READER TAKE READING OF INDUSTRIAL CONSUMER.THEY ALWAYS ASK HOW TO INCREASE POWER FACTOR FROM 60% TO 99 % TO AVOID PENALTY OF POWER FACTOR.

3 Answers  

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What is the minimum insulation value required for a cable between phase to phase and phase to earth of 380 Vac 50Hz circuit, having load arround 800 amps.

2 Answers   DEWA, TATA,

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in transformers for ex. 100mva and 400kv the secondary current is about 420 amps but for selection of bushing the capacity of selected bushing is 2000A why there is such big difference ?

2 Answers   ABB,

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we change the speed of the synchronous motor by incresing or decreasing a rotor resistance

1 Answers  

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if we are using ACB in a panel the how much clearance do we need in panel room.

2 Answers  

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how starting current in motor is reduced in case of motor in star connection.

4 Answers   Adhunik,

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we have a rewind motor of 2Hp,2800Rpm, 220Volt AC. how can we choose the running capacitor for this motor, any formula for that?

0 Answers  

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