# Order

- Harmonic of the rotational speed of rotating machinery. As an example, in the case of the shaft rotating at 6,000 rpm, the first order component occurs at a frequency of 100 Hz (6,000/60), whereas the third order component would occur at a frequency of 300 Hz.

- where
*f*= frequency [Hz]*n*= order*N*= rotational speed [rpm]

**See also: **Order Analysis, Order Tracking.

**Subjects: ** Noise & Vibration