What is the most common arc initiation method that involves establishing a low-voltage and low-current, high-frequency arc?

The method that establishes a low-voltage and low-current, high-frequency arc is known as discharge starting using a pilot arc. This technique is effective in creating an initial plasma arc necessary for cutting.

In this method, a high-frequency generator produces a brief, high-voltage spark that ionizes the air and establishes a pilot arc between the electrode and the workpiece. This allows the operator to create the cutting arc without making direct contact, which can be critical for preventing damage to the cutting torch and ensuring a clean initiation of the cutting operation.

Other initiation methods, such as contact starting, involve directly touching the workpiece with the electrode to initiate the arc, which is less commonly used in modern plasma cutting due to potential wear and damage to the nozzle or electrode. Circuit starting and continuous starting do not specifically focus on creating the pilot arc with the same efficiency and effectiveness as discharge starting, making them less prevalent in professional plasma arc cutting practices.