This International Standard specifies requirements which it is necessary for a measuring instrument for vibration severity of machines to meet if inaccuracies of measurement made on the casing of machines, particularly when making repeated measurements for trend monitoring of a certain machine, are not to exceed a specific value.
The instruments covered by this International Standard give direct indication or recording of root-mean-square (r.m.s.) vibration velocity that is defined as a measurement unit.
NOTE1 A method of checking true r.m.s. indication is described in AnnexA. This method is mainly retained for instruments not based on modern analogue to digital conversion and numerical calculation of r.m.s., but can also be applied to instruments which are so based.
NOTE2 Subject to adaptation of the measurement frequency range, these instruments can be used for other applications where similar accuracy of measurement is required, measurement of vibration velocity of structures, tunnels, bridges, etc. Optionally phase measurements may be included.