what is the mechanism of operation of brushless dc motor why is it more wexpensive then ordinary permanent magnet motors

0 Answers   Lanco,

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Dear sir, How to calculate 3.5 core pvc aluminium armoured cable meter wise,give with best examples.... please help me in this regards....

1 Answers   Modi Builders,

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In alternator generally we give DC voltage to field of alternator but field (excitor)produce Ac & converts into DC by rotating rectifier(RR ) then fed to rotor .my question is why we cannot give dc voltage directly to rotor instead of Excitor & RR ?

1 Answers  

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We have .ht motor which is 60Hz.we run on 50Hz.so that it's speed reduce but we had one prob.that motor winding temp increase up to 135 deg.we want reduce this temp.what to do?we arrange ext.cooling fan but not much effect.we want reduce this temp. Inhouse without affecting much.cost. also don't want reWINDING OF MOTOR?

3 Answers  

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Phase control and integral control are used for?

0 Answers   NPCIL,

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for ac networks if the voltage wave form is V=Vm sinwt here the voltage Vm=230 for the frequency 50hz then the time period is 0.02 sec then for the time period 0.12 sec what is the voltage

4 Answers  

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hi frnds what is meant by harmonics & what is meant by third hormonics,where its will occur ?thank u

0 Answers  

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Why A.C. capacity given in Ton. Ex. - 1.5 Ton

4 Answers   Samsung, UltraTech,

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which pump used in STP

0 Answers   Dalkia,

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if acapacitor connected to power supply will it cosume power& will it going to get recorded in energy meter

2 Answers  

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how to handle 2500 kva transformar

0 Answers  

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What is the main cause of magnetism?

0 Answers  

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