What is the capacitor?

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 The Capacitor.         A capacitor is formed when two conductors, usually of aluminium, are separated by an insulator sus as paper ect. For use in motors the strips are rolled together into a compact unit and placed into a sealed metal or plastic container. This may be either cylinderical or rectangular in shape and may be mounted on, in, or away from the motor. Two terminals or leads are provied for connection. The name capacitor is descriptive of the operation of the device. The capacitor acts essentially as a storage units that is,has capacity to store electricity and provides a leading current to the auxiliary or starting winding. All capacitors have this quality and all are electrically the same;they differ only in mechanical construction.     THE OIL-FILLED CAPACITOR                 This capacitor is used mainly in the permanent-split capacitor motor and for the two-value capacitor motor. The capacitor use an oil-impregnated paper as the dielectric and are permanently conne
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What is the reason of a motor runs with less than actual speeds?

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What is the reason of a motor runs with less than actual speed????
       Tell the remedies also.
   1. Short circuit inrunnig winding: The motor runs slow due to short critics in running winding coils. This motor jamps also. If this motor runs for a long time,it may burn. This fault may be determined by touching with hand or by internal growler. Its coils are to be rewound.
  2.  It may be possible that the starting winding is not cut off from the supply and the motor gives humming sound. For this,run the motor leaving the centrifugal switch out of circuit and taking starting winding leads out. If it is running O.K.then change the centrifugal switch or repair it,if possible by giving washer etc.
     3. Reverse in running winding,.. It may be possible that the poles of running winding have been reversed when connection of a new winding are done. Check the polarity of poles by compass needle or screw drivers as stated above and correct if wrong.

     4.   Faulty capacitor.      Mostly in capacitor motor the fault is due to capacitors. The best remedy is to change the capacitor by a new one. If the motor runs correctly, then the fault of capacitor is clear and if the motor dose not run properly there is some other fault.
      5.  Defective bearings...  Due to defective bearings the motor runs with slow speed and abnormal sound. Due to small air gap between rotor and stator the rotor rubs with the stator and sound. bearing should be replaced.
      6.   Loose rotor bars.... The looseness of rotor basis known when motor takes less load and gives crowling sound. Check the rotor bars by taking out the rotor. Check them on growler also the loose rotor bar gives flickering in the lamp fitted on the growler. Move the rotor on the growler to locate defective bar and sloder the defective (I.e.loose) rotor bars.

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