Examining Measured Sound Power Variances in Telecommunications Equipment

摘要

In ISO 9296, First Edition Section 4.4 - Determination of the Declared Noise Emission Values, it states that the production variations shall be taken in to account for the declaration of Sound Power values. Specifically, Section 4.4.2 states that for an individual machine, the value K (2.5 decibels) rounded up to 3 decibels (dB) shall be added to the measured sound power value in order to obtain the Declared Sound Power Value when measuring an individual machine. This paper seeks to examine actual manufacturing variances by presenting real measured values of large telecommunications equipment and to determine if these measured acoustic sound power variances are tighter than 3 dB.