Why the brushes used in dc machines are made of carbon not from other metal?

3 Answers  

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in dc series motor if field wdg is shorted then

0 Answers  

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Control wiring of a dol starter for forward and backward

0 Answers   Basj Industries,

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i have a 1500kVA transformer what is the kWH meter i need to use?

0 Answers   HP, L&T, Mohammed Harasani Architects,

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what are the stresses in circuit breakers ?

0 Answers  

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how to calculate size of cable from motor current given and how to calculate full load current of a induction motor.

3 Answers   Aarti Steels,

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Why only sinusoidal ac voltages are generated?why not triangular or sawtooth?

0 Answers  

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Why we use three phase world wide why not four phase or five phase being used?

8 Answers  

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why we use condenser in the thermal power plant, althrough the same vapour will be again heated

0 Answers   Bhel,

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If one 10 Hp 3phase induction motor connected in 380volt 50Hz. and again its connected to 380volt 60Hz. howmuch currrent and power take on both time?????

1 Answers  

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Give the expression for the frequency of oscillations in an op-amp sine wave oscillator?

0 Answers  

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What is the maximum and minimum rating of UPS?

0 Answers   Indiabulls,

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