Duty cycle tells us how long a machine can operate within a 10 minute period. In theory, a system with a 100 percent duty cycle can run for 10 out of 10 minutes, while a system with a 50 percent duty cycle is designed to run for 5 out of 10 minutes, and so on. In reality, though, duty cycle can’t simply be listed as a percentage of “on time” in a given period. Many factors, such as the output power of a system, the thickness of the metal you are cutting, ambient temperature and more, go into determining duty cycle.

For example, your arc is longer and therefore arc voltage is higher when cutting thicker materials, and shorter and lower when cutting thinner materials. This makes it possible to run at full output amperage when cutting gauge material without exceeding the duty cycle of a plasma system, even if the system is said to have a 50 percent duty cycle.