What is Duty Cycle?
Duty cycle is the ratio of how long something is turned on for, in relation to total time. It describes the relationship between total time on, compared to time off, and is expressed as a percentage of total time.
For example, if a cycle of a particular on/off function took 10 seconds, and the duty cycle was measured at 30%, then the total time the test subject was on for would be 3 seconds. (30% of 10 seconds)
This may be useful if measuring a pulse wave from a digital source, or measuring how often a machine is doing a particular task, or how often a signal is received from a particular input.
Most good digital multimeters have a duty cycle function as duty cycle is closely related to frequency. In fact, it is usually found in the same settings that the frequency is located.