Why is welding power source duty cycle important?
The duty cycle of a welding power source is the amount of time you can weld at a given output without having to worry about overheating or burning up the power source. In the United States and some other countries, duty cycle is based upon a 10 minute period of time. For example, if a machine is rated at 300 amps/60% duty cycle, it can weld at 300 amps for six minutes. For the remaining four minutes, the power source needs to idle and cool. The duty cycle for many machines goes up as the amperage goes down. A typical duty cycle for a hobbyist-type TIG welder would be 20%. An automatic setup for TIG, on the other hand, can require a 100% duty cycle because of the long weld times possible. Duty cycles of about 40% – 60% are often sufficient for many handheld TIG applications in construction and industry. 8. When is a “high frequency,” “scratch start,” or some other method of starting the arc used? Whether welding in the DC EN mode (the normal mode for work on ferrous metal) or the AC mod
