Page 47 - CITS - Welder - Trade Theory
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WELDER - CITS



           AC to DC Generator













           Working principle of DC  Generator
           The armature is made to rotated with the help of a prime mover between the main poles, where a strong magnetic
           field exists.
           The armature cuts  the  magnetic lines of  force,  generating EMF  in the conductors.  The  commutator,  being
           connected to the armature conductors, changes the generated alternative current into DC.
           The generated DC is then taken to the generator terminal through the carbon brushes.
           Note - Where the main supply electricity is available. Used as a prime AC motor.
           Where main supply is not available, petrol or diesel engine may be used as a prime mover.
           Diesel welding generator


























            Rectifier and inverter welding machine


           Objectives: At the end of this lesson you shall be able to
           •  explain DC welding rectifier and inverter set
           •   explain the working principle of rectifier and inverter set.


           Introduction  to rectifier welding machine
           A welding rectifier set is used to convert AC welding into DC welding supply. It consists of a step down transformer.
           Welding current rectifier cell convert to AC to DC current.
           The rectifier cell consists of a supporting plat made of steel or aluminum. Rectifier plate with a thin layer of nickel
           or Bismith, spreyed with selenium or silicon.
           It is finally covered with an alloyed film of cadmium, Bismith and Tin.







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                                         CITS : C G & M - Welder - Lesson 8&9
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