Vibration Theory & Terminology: Frequency
Frequency is defined as the rate at which an event occurs during a given period of time. With a vibration, the event is a cycle, and the period of time is one second. Thus, frequency is expressed in cycles per second. See Fig 1 . The proper term for cycles per seconds is Hertz (Hz). This is the most common way to measure frequency. Multiply the hertz by 60 to get the cycles or revolutions per minute (RPM).