The sustained, reliable operation of a repetitive, high‐current pulsed arc discharge in a large‐volume container has been found to require the use of ignition enhancing techniques to maintain adequate turn‐on reproducibility. Application of a few grams of 20‐mesh granulated zinc to a portion of the copper cathode surface produces a striking reduction in the rise time and turn‐on reliability of pulses carrying up to 1000 A.