is the amount of time a compressor is running vis-à-vis the total cycle time. Thus it is the ratio of compressor run time to the total cycle time.
Duty cycle = Compressor Run Time / (Run Time + Off Time)
The duty cycle is generally accepted as a guideline to help user understand how often a compressor cycles on and off while working. However, there is no standard definition all manufacturers use to describe their compressor’s duty cycle. Because of this, some manufacturers may not list duty cycle ratings.