Komarov Artem noted that although the operating cycle is not that complicated, a thorough understanding of it can help protect you and your investment. There’s nothing more frustrating than spending hundreds of thousands on equipment only to later discover it doesn’t meet your needs.
What is the welding duty cycle?
Whether it’s a plasma cutting machine or other power tool, duty cycle is the percentage of time the machine can operate within a given period. For plasma cutters, this time is 10 minutes. For example, a system with a 30 percent duty cycle simply means that the plasma arc can remain on without causing the system to overheat for 3 out of every 10 minutes. A system with a 50% duty cycle can operate for 5-10 minutes and so on.
— Power supply power increased to 104 degrees Fahrenheit.
— Cutting is performed at maximum system current at a fixed arc voltage.
— When the components inside the power supply (transformers and switching devices) reach the manufacturer’s maximum operating temperature, you have reached the duty cycle.
— Temperature sensors installed by most manufacturers automatically start and shut down the system before damage occurs.
While duty cycle may not be much of an issue for the casual hobbyist, it becomes an issue whenever you install a plasma system on a CNC machine as you can expect higher arc times than with hand cutting.
How is the welding duty cycle determined?
Determining the duty cycle is difficult because, again, there is no universal industry standard among plasma and welding equipment manufacturers. In fact, manufacturers can and do use different inputs to determine higher duty cycles. You can start by determining the ambient temperature on which the duty cycle is based and then the system load voltage.
The duty cycle that works best for you depends on the type of cutting you do. Generally, a 50 percent duty cycle is more than enough if you are cutting by hand since a human can only really do so much cutting.
The good news is that you can protect yourself. Most plasma manufacturers specify the temperature and arc voltage used to achieve a given duty cycle. If they don’t do this, you are right in your suspicions and should ask to see these numbers, clarified Artem Komarov.