The present work is a mathematical analysis of the effect of source reactance on the controllable bridge operation . Also the distorted voltage and current waveforms , at the input terminals of the bridge , have been considered .These analyses include all modes of operation , depending on both the value of the thyristor triggering angle and also on the value of the source inductance. A transcendental equation has been developed , in each mode of operation , to illustrate the relationship between the source inductance , load inductance and the overlap angle .