Answer / thowsif_emerson

An electrical ballast (sometimes called control gear) is a
device intended to limit the amount of current in an
electric circuit.

In DC motor,the field MMF is given by NI.N-no.of field winding turns,I-excitation and both are constant.Then how could the main flux decreases due to armature reaction.

4 Answers   Bhel, IBM,

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Hi Suppose we have a wye/wye transformer which is grounded at both sides,in this situation, do we have ay ground transformer? in other words, ground transformer can do any thing more (while we have nuetral wire in both sides)? As the last question, what about 3rd harmonic? we have two choices: first using wye/delta transformer + ground transformer and second using wye/wye earthed connection.in the former choice, we dont have 3rd harmoonic at the secondary side but what about Yn/yn conection? do we suffer from 3rd harmonic in the Yn/yn connection?

0 Answers  

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For refrigerators the motor current is raised beyond its rating on both conditions when the voltage of the system is more(say 270v) than the rated voltage(220v) as well as when the voltage of system is less(say 160v) than normal voltageof 220v, why explain?

0 Answers   Electrical Tech, UPSE,

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which of the folowing has negative temperature coefficient of resistance? a. mercury b. copper c. lead d. carbon

2 Answers  

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what is the power factor

13 Answers   Heidelberge Cement,

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please send me last 5 year interview questions

0 Answers   ONGC,

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we have a 2.5hp Starite electric motor water pump,the elec motor burned out,we need to replace starting capacitor(old capacitor specs erased),what microfarad rating capacitor do we need? 110-125V

0 Answers  

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Why phase sequence must be same in any ht motor or generator circuit?if phase sequence doesn't same whatever will be affect on circuit?

0 Answers  

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How Can You Relate Power Engineering With Electrical Engineering?

0 Answers   ABB,

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in dc machines in the armature nature of power is ac but why we take rasistance instead of impedance?

1 Answers  

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please explain to me how to calculate current,voltage,resistance with formula??

0 Answers  

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Is there any particular formula for sizing the bus bar based on the current rating

1 Answers   Bunt Solar,

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