Developments in the design of AC Welding Plant

The construction of the conventional manual-arc (MMA) welding transformer has remained almost unchanged for many years. However, as AC welding has some special features there is a need to study alternative possibilities for further development of AC welding equipment's. The following article considers various control principles and the use of semi-conductors and special circuits to produce square-wave welding current for improved welding characteristics and improved satety.