Plasma cutters have also been used in CNC (computer numerically controlled) machinery. Manufacturers build CNC cutting tables, some with the cutter built in to the table. The idea behind CNC tables is to allow a computer to control the torch head making clean sharp cuts. Modern CNC plasma equipment is capable of multi-axis cutting of thick material, allowing opportunities for complex welding seams on CNC welding equipment that is not possible otherwise. For thinner material cutting, plasma cutting is being progressively replaced by laser cutting, due mainly to the laser cutter's superior hole-cutting abilities.

The Pilot Arc type uses a two cycle approach to producing plasma. First, a high-voltage, low current circuit is used to initialize a very small high intensity spark within the torch body, thereby generating a small pocket of plasma gas. This is referred to as the pilot arc. The pilot arc has a return electrical path built into the torch head. The pilot arc will maintain until it is brought into proximity of the workpiece where it ignites the main plasma cutting arc. Plasma arcs are extremely hot and are in the range of 15,000 degrees Celsius.

Analog plasma cutters, typically requiring more than 2 kilowatts, use a heavy mains frequency transformer. Inverter plasma cutters rectify the mains voltage into DC, which is fed into either an IGBT or a MOSFET. IGBT transistors operate independently of one another whilst MOSFET transistors need to be paralleled. With paralleled MOSFET transistors if one of the transistors activates prematurely it can lead to a cascading failure of one quarter of the inverter. IGBT transistors do not have this problem as they are independent however are very expensive to manufacture and generally used in high current machines where it is not possible to parallel sufficient MOSFET transistors. The transistors are switched at thousands of Hertz, which greatly reduces the magnetic flux in the step down transformer, and therefore the size of the transformer is reduced accordingly. The switch mode topology is referred to as a dual transistor off-line forward converter.