Page 45 - CITS - Welder - Trade Theory

WELDER - CITS

Working Principle

Two welding cables are attached with the output terminals. One is for the electrode and the other is for earth or
job.
The transformer may be air – cooled or oil- cooled.

The AC main supply (220 -440 volts) is connected to the primary winding which produces a magnetic lines of
force in the iron core.
The magnetic lines of force affects the secondary winding and induces high ampere – low voltage welding supply
in it.
The voltage at the primary coil is reduced in the secondary coil depending on the ratio of the No. of turns in the
primary to that of the secondary.
Voltage at primary coil X No. of turns in the secondary
Voltage at secondary coil =
No of turns in the primary

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