Which statement about 60% duty cycle operation is correct according to the material?

• A. It cannot be operated continuously for 12 minutes
• B. It can run continuously for 12 minutes
• C. It can operate for 12 + 8 minutes
• D. It must always cool after 6 minutes

Answer: (A)

Duty cycle shows how long a tool can be on versus off in a repeating cycle to avoid overheating. A 60% duty cycle means the device can be energized for 60% of each cycle and must be off the remaining 40% to cool.

If that cycle lasts 12 minutes, the maximum on-time is 0.60 × 12 = 7.2 minutes. So you cannot run continuously for the full 12 minutes without exceeding the 60% limit. The idea that it can run for 12 minutes straight ignores the duty-cycle restriction. The notion of 12 plus 8 minutes isn’t how a single duty cycle works, and there isn’t a universal rule to cool after exactly 6 minutes—the cooling time is determined by the cycle’s on/off requirements. Therefore, the statement that it cannot be operated continuously for 12 minutes is the correct interpretation.