Answer Posted / d.g.skandan

No load current of a 3phase induction motor varies
according to its KW and rpm. Normally as a thumb rule
fraction HP motors (below 2.2KW) will be 50% of full load
current. Above 2.2KW may be 20% to 30% OF full load
current.

Why does increasing the magnetic flux in the main field of a d.c motor cause the armature current to reduce??

2033

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Classify milling machines.

1129

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explain comutator action in detail.thanks

2253

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whats the application of voltage regulation? and whats the voltage regulation's device?

1890

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1.what is meaning of curve into a mcb. 2.what is basic reason changing of curve

1997

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i am an maintenance engineer. one distribution board have 5 feeder. recently its ELR trips frequently, but it take some times after trip( 10min,20min..)but 3 feeder no load. two feeder only loaded. i checked one feeder IR value all values are above 50Mohm.but B phase to Earth is only 9Mohm.any problem about low value

1942

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for 100 HP Induction motor service factor is 1.2(SF) we placed a VFD at the motor side load is balance with 0.3 Amp's Phase to Phase but at incoming of VFD load is un-balance with 10 to 20 Amp's what will be cause of load un balance

1945

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What is gain margin?

1080

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What will be the impact on motor performance if a LT motor is rewound with changed motor winding data as given below:- Original winding data: total 04 wires = 02 wires of 17 SWG + 02 wires of 16.5 SWG. Changed Winding data: total 03 wires of 15.5 SWG wire size Motor rating: 160KW, 740RPM, 415V, ID FAN application. Normal Running Current = 95% of FL Current.

2040

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How many Zones can be in Conventional type fire alarm system & how can we detect the fire in Conv. type FAS?

1823

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Please explain, how to test vector group of tranformer(Delta y1) . Thank

1696

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what is the difference between single ratio, multiple core and multiple ratio, multiple core ? please explain.

2189

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how does the thyistor work in dc drive?

1980

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I need to connect a synchronous generator to the grid using automatic synchronization and two circuit breakers (one for synchronization, one for end connection to the grid), how to determinate the required diameter of the cables?

2572

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what is earth pit , how we can measured it, what earth rods reference

2614

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