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 Tracking.