The power quality deterioration has been significantly increased in the recent past due to the harmonics introduced by variable frequency derives and non-linear loads. Welding transformer with irregular duty cycle has a major contribution in increases the THD level. This paper presented the analysis of relationship between loss in welding transformer and harmonics. Under over rated units in welding works plays prime role in loss component and excess of inrush current drawn by the welding

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... rmer. Selection of appropriate unit rating for welding works significant simultaneously control the sudden increases and drawn of load current and fruitful in transient suppression. Real time approach of investigation deviation much from simulation one. The experimental results on different ratings unit before and after treatment have been investigated, and effect of improvement in the performances during both standby and welding period has been recorded. Power quality analysis of welding business for harmonic distortion has been carried out using power quality analyser.