Page 46 - CITS - Welder - Trade Theory

WELDER - CITS

DC welding motor generator set

Objectives: At the end of this lesson you shall be able to
• explain, DC welding generator set
• explain the construction of DC generator set
• explain the working principle of DC welding motor generator set.

Introduction
Generate DC welding supply with the help of AC main supply. A DC welding generator produces direct current in
either straight or reveres polarity. The current supply by DC generator is created by an armature rotating in the
electrical field. And armature is rotated by AC electric motor.
Commutators convert to AC to DC current.
Generators are designed to rotate at speed1500, 1800, or 3600 rpm to give option current values.

Generator supplies voltage usually in the range from 15 to 45 volts across the arc.
DC welding generator

Construction of DC generator
Main polies - These are connected to the body or yoke to produce magnetic line of force, also called Field coils.
Body/ yoke - It is the body of the generator which covers all the parts and helps in completing the magnetic circuit
to the generate electricity.

Armature - It is a laminated steel drum with longitudinal slots which accommodate copper conductors.

Commutators - It is made out of copper segments separated by mica insulation. It is also mounted on the shaft
along with the armature and is connected to the armature conductors.
Carbon Brushes - These are mounted on the body to the have connected to the rotating commutator and are
connected to the output terminals.

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